Species Report
9090 Records
Here are all the species that match your criteria. Please click on the the Scientific Name to find out more about the particular species.
| Inverted Common Name | Scientific Name | Where Listed | Lead Region | Listing Status |
|---|---|---|---|---|
| Abalone, Black | Haliotis cracherodii | - | NMFS | PE |
| Abalone, White | Haliotis sorenseni | North America (West Coast from Point Conception, CA, U.S.A., to Punta Abreojos, Baja California, Mexico) | NMFS | E |
| Acacia, Emory | Acacia emoryana | - | 2 | RT |
| Acornshell | Epioblasma haysiana | - | 4 | RT |
| Acornshell, southern | Epioblasma othcaloogensis | - | 4 | E |
| Addax | Addax nasomaculatus | - | Foreign | E |
| Adder's-mouth | Malaxis brachypoda | - | 1 | SC |
| Adder's-tongue, California | Ophioglossum lusitanicum | - | 1 | RT |
| Adder's-tongue, [unnamed] | Ophioglossum concinnum | - | 1 | RT |
| Adjutant, greater | Leptoptilos dubius | - | Foreign | PE |
| Admiral, Nevada | Limenitus weidemeyerii nevadae | - | 1 | SC |
| Adobe-lily, greenhorn | Fritillaria striata | - | 1 | RT |
| Adobe-lily, [unnamed] | Fritillaria pluriflora | - | 1 | SC |
| adolphia, California | Adolphia californica | - | 8 | SC |
| Agastache, small-leaved | Agastache parvifolia | - | 1 | RT |
| Agave, Arizona | Agave arizonica | - | 2 | DO |
| Agave, Chisos | Agave glomeruliflora | - | 2 | SC |
| Agave, Clark Mountains | Agave utahensis nevadensis | - | 1 | RT |
| Agave, ivory-spined | Agave utahensis eborispina | - | 1 | RT |
| Agave, Santa Cruz striped | Agave parviflora parviflora | - | 2 | SC |
| Agave, Shaw's | Agave shawii | - | 1 | SC |
| Agave, sp. nov. ined. (Tonto Basin) | Agave sp. | - | 2 | SC |
| Akekee | Loxops caeruleirostris | - | 1 | E |
| Akepa, Hawaii (honeycreeper) | Loxops coccineus coccineus | - | 1 | E |
| Akepa, Maui (honeycreeper) | Loxops coccineus ochraceus | - | 1 | E |
| Akialoa, Kauai (honeycreeper) | Hemignathus procerus | - | 1 | E |
| Akiapola`au (honeycreeper) | Hemignathus munroi | - | 1 | E |
| Akikiki | Oreomystis bairdi | - | 1 | E |
| Ala balik (trout) | Salmo platycephalus | - | Foreign | E |
| Alani | Melicope adscendens | - | 1 | E |
| Alani | Melicope balloui | - | 1 | E |
| Alani | Melicope christophersenii | - | 1 | C |
| Alani | Melicope cruciata | - | 1 | SC |
| Alani | Melicope degeneri | - | 1 | E |
| Alani | Melicope haleakalae | - | 1 | SC |
| Alani | Melicope haupuensis | - | 1 | E |
| Alani | Melicope hawaiensis | - | 1 | RT |
| Alani | Melicope hiiakae | - | 1 | C |
| Alani | Melicope kavaiensis | - | 1 | RT |
| Alani | Melicope knudsenii | - | 1 | E |
| Alani | Melicope lydgatei | - | 1 | E |
| Alani | Melicope macropus | - | 1 | RT |
| Alani | Melicope makahae | - | 1 | C |
| Alani | Melicope mucronulata | - | 1 | E |
| Alani | Melicope munroi | - | 1 | E |
| Alani | Melicope nealae | - | 1 | SC |
| Alani | Melicope obovata | - | 1 | RT |
| Alani | Melicope orbicularis | - | 1 | RT |
| Alani | Melicope ovalis | - | 1 | E |
| Alani | Melicope ovata | - | 1 | RT |
| Alani | Melicope pallida | - | 1 | E |
| Alani | Melicope paniculata | - | 1 | E |
| Alani | Melicope puberula | - | 1 | E |
| Alani | Melicope quadrangularis | - | 1 | E |
| Alani | Melicope reflexa | - | 1 | E |
| Alani | Melicope saint-johnii | - | 1 | E |
| Alani | Melicope sandwicensis | - | 1 | RT |
| Alani | Melicope wailauensis | - | 1 | SC |
| Alani | Melicope zahlbruckneri | - | 1 | E |
| Ala`a | Pouteria auahiensis | - | 1 | RT |
| Ala`a | Pouteria hotteana | - | 4 | SC |
| Ala`a | Pouteria rhynchosperma | - | 1 | RT |
| Albatross, Amsterdam | Diomedia amsterdamensis | - | Foreign | E |
| Albatross, black-footed | Phoebastria nigripes | - | 1 | UR |
| Albatross, short-tailed | Phoebastria (=Diomedea) albatrus | - | 7 | E |
| Alder, seaside | Alnus maritima | - | 5 | RT |
| Ale | plantago princeps var. anomala | - | 1 | E |
| Ale | plantago princeps var. longibracteata | - | 1 | E |
| Alethe, Thyolo | Alethe choloensis | - | Foreign | E |
| Algodoncillo | Psiguria cookiana | - | 4 | SC |
| Alice-flower, wonderland | Aliciella (=Gilia) cespitosa | - | 6 | RT |
| Alkali grass, Howell's | Puccinellia howellii | - | 1 | SC |
| Alkali grass, Parish's | Puccinellia parishii | - | 2 | RT |
| Alkali grass, [unnamed] | Puccinellia triflora | - | 7 | RT |
| Alligator, American | Alligator mississippiensis | - | 4 | SAT |
| Alligator, Chinese | Alligator sinensis | - | Foreign | E |
| Allocarya, Calistoga | Plagiobothrys strictus | - | 8 | E |
| Allocarya, Cedar Crest | Plagiobothrys glyptocarpus modestus | - | 1 | SC |
| Allocarya, glabrous | Plagiobothrys glaber | - | 1 | RT |
| Allocarya, scribe | Plagiobothrys scriptus | - | 1 | RT |
| Alopecurus, Sonoma | Alopecurus aequalis var. sonomensis | - | 8 | E |
| Alumroot, Duran's | Heuchera duranii | - | 1 | RT |
| Alumroot, island | Heuchera maxima | - | 1 | RT |
| Alumroot, Laguna | Heuchera brevistaminea | - | 1 | RT |
| alumroot, shaggyhair | Heuchera hirsutissima | - | 1 | SC |
| Alumroot, [unnamed] | Heuchera americana hispida | - | 5 | RT |
| Amaranth, seabeach | Amaranthus pumilus | - | 4 | T |
| Ambersnail, Kanab | Oxyloma haydeni kanabensis | - | 6 | E |
| Ambrosia, San Diego | Ambrosia pumila | - | 8 | E |
| Ambrosia, south Texas | Ambrosia cheiranthifolia | - | 2 | E |
| Ambrosia, [unnamed] | Ambrosia linearis | - | 6 | SC |
| Amole, Camatta Canyon | Chlorogalum purpureum reductum | - | 1 | SC |
| Amole, purple | Chlorogalum purpureum | - | 8 | T |
| Amorpha, Texas | Amorpha roemeriana | - | 2 | RT |
| Amphianthus, little | Amphianthus pusillus | - | 4 | T |
| Amphipod, Alabama well | Stygobromus smithi | - | 4 | SC |
| Amphipod, Allegheny cave | Stygobromus allegheniensis | - | 5 | RT |
| Amphipod, anomalous spring | Crangonyx anomalus | - | 3 | RT |
| Amphipod, Appalachian Valley cave | Crangonyx antennatus | - | 4 | RT |
| Amphipod, Arizona cave | Stygobromus arizonensis | - | 2 | UR |
| Amphipod, Balcones cave | Stygobromus balconis | - | 2 | SC |
| Amphipod, Barr's cave | Stygobromus barri | - | 3 | SC |
| Amphipod, Bath County cave | Stygobromus mundus | - | 5 | SC |
| Amphipod, bifurcated cave | Stygobromus bifurcatus | - | 2 | SC |
| Amphipod, Bigger's | Stygobromus biggersi | - | 5 | SC |
| Amphipod, Bousfield's | Gammarus bousfieldi | - | 4 | SC |
| Amphipod, Bowman's cave | Stygobromus bowmani | - | 2 | SC |
| Amphipod, Burnsville Cove cave | Stygobromus conradi | - | 5 | SC |
| Amphipod, Cascade Cave | Stygobromus dejectus | - | 2 | SC |
| Amphipod, cave | Stygobromus phreaticus | - | NA | RT |
| Amphipod, Central Kentucky cave | Stygobromus exilis | - | 4 | RT |
| Amphipod, Central Missouri cave | Allocrangonyx hubrichti | - | 3 | SC |
| Amphipod, Clanton's cave | Stygobromus clantoni | - | 6 | SC |
| Amphipod, Cooper's cave | Stygobromus cooperi | - | 5 | SC |
| Amphipod, Culver's cave | Stygobromus culveri | - | 5 | SC |
| Amphipod, Dearolf's cave | Crangonyx dearolfi | - | 5 | SC |
| Amphipod, Devil's Sinkhole | Stygobromus hadenoecus | - | 2 | SC |
| Amphipod, diminutive | Gammarus hyalleloides | - | 2 | C |
| Amphipod, Elevated Spring | Stygobromus elatus | - | 4 | RT |
| Amphipod, Ephemeral cave | Stygobromus ephemerus | - | 5 | RT |
| Amphipod, Ezell's Cave | Stygobromus flagellatus | - | 2 | SC |
| Amphipod, Florida cave | Crangonyx grandimanus | - | 4 | SC |
| Amphipod, Franz's | Stygobromus franzi | - | 5 | RT |
| Amphipod, Grady's cave | Stygobromus gradyi | - | 1 | UR |
| Amphipod, Greenbrier Cave | Stygobromus emarginatus | - | 5 | RT |
| Amphipod, Hara's cave | Stygobromus harai | - | 1 | UR |
| Amphipod, Hay's Spring | Stygobromus hayi | - | 5 | E |
| Amphipod, Hobb's cave | Crangonyx hobbsi | - | 4 | SC |
| Amphipod, Illinois cave | Gammarus acherondytes | - | 3 | E |
| Amphipod, Iowa | Stygobromus iowae | - | 3 | RT |
| Amphipod, Kansas well | Bactrurus hubrichti | - | 2 | RT |
| Amphipod, Kauai cave | Spelaeorchestia koloana | - | 1 | E |
| Amphipod, Kenk's | Stygobromus kenki | - | 5 | UR |
| Amphipod, long-legged cave | Stygobromus longipes | - | 2 | SC |
| Amphipod, MacKenzie's cave | Stygobromus mackenziei | - | 1 | UR |
| Amphipod, Malheur Cave | Stygobromus hubbsi | - | 1 | UR |
| Amphipod, Minor cave | Crangonyx minor | - | 3 | RT |
| Amphipod, minute cave | Stygobromus parvus | - | 5 | SC |
| Amphipod, Morrison's cave | Stygobromus morrisoni | - | 5 | SC |
| Amphipod, mountain cave | Stygobromus montanus | - | 4 | RT |
| Amphipod, Noel's | Gammarus desperatus | - | 2 | E |
| Amphipod, Norton's cave | Stygobromus nortoni | - | 4 | SC |
| Amphipod, Oklahoma cave | Allocrangonyx pellucidus | - | 2 | SC |
| Amphipod, Onondaga Cave | Stygobromus onondagaensis | - | 3 | RT |
| Amphipod, Oregon cave | Stygobromus oregonensis | - | 1 | RT |
| Amphipod, Ozark cave | Stygobromus ozarkensis | - | 3 | RT |
| Amphipod, Packard's cave | Crangonyx packardi | - | 3 | RT |
| Amphipod, Peck's cave | Stygobromus (=Stygonectes) pecki | - | 2 | E |
| Amphipod, Pecos | Gammarus pecos | - | 2 | RT |
| Amphipod, Pickle Springs | Stygobromus heteropodus | - | 3 | RT |
| Amphipod, Pizzini's | Stygobromus pizzinii | - | 5 | SC |
| Amphipod, Pocahontas cave | Stygobromus nanus | - | 5 | SC |
| Amphipod, Potomac groundwater | Stygobromus tenuis potomacus | - | 5 | RT |
| Amphipod, redacted cave | Stygobromus redactus | - | 5 | SC |
| Amphipod, Redell's cave | Stygobromus reddelli | - | 2 | SC |
| Amphipod, Rubious Cave | Stygobromus lucifugus | - | 3 | RT |
| Amphipod, Shenandoah Valley cave | Stygobromus gracilipes | - | 5 | RT |
| Amphipod, Southwestern Virginia cave | Stygobromus mackini | - | 4 | RT |
| Amphipod, Spring Cave | Stygobromus spinatus | - | 5 | SC |
| Amphipod, Stellmack's cave | Stygobromus stellmacki | - | 5 | SC |
| Amphipod, subtle cave | Stygobromus subtilis | - | 3 | SC |
| Amphipod, tidewater | Stygobromus indentatus | - | 5 | SC |
| Amphipod, tidewater interstitial | Stygobromus araeus | - | 5 | SC |
| Amphipod, undescribed | Crangonyx sp | - | NA | SU |
| Amphipod, Wengerors' cave | Stygobromus wengerorum | - | 1 | UR |
| Amphipod, Wisconsin well | Stygobromus putealis | - | 3 | SC |
| Amphipod, [unnamed] | Stygobromus hoffmani | - | 5 | SC |
| Amphiuma, One-toed | Amphiuma pholeter | - | 4 | SC |
| Ancylid, domed | Rhodacmea elatior | - | 4 | SC |
| Ancylid, hood | Ferrissia mcneili | - | 4 | SC |
| Ancylid, wicker | Rhodacmea filosa | - | 4 | SC |
| Andrenid bee, Antioch | Perdita scitula antiochensis | - | 1 | SC |
| Andrenid bee, yellow-banded | Perdita hirticeps luteocincta | - | 1 | SC |
| Anemone, Edge Falls | Anemone edwardsiana petraea | - | 2 | SC |
| Anemone, [unnamed] | Anemone edwardsiana edwardsiana | - | 2 | RT |
| Anemone, [unnamed] | Anemone minima | - | 5 | RT |
| Anemone, [unnamed] | Anemone oregana felix | - | 1 | RT |
| Angelica, Call's | Angelica callii | - | 1 | RT |
| Anglepod, Falfurrias | Matelea radiata | - | 2 | SC |
| Anglepod, [unnamed] | Matelea alabamensis | - | 4 | SC |
| Anglepod, [unnamed] | Matelea baldwyniana | - | 4 | SC |
| Ani, smooth-billed | Crotophaga ani | - | 4 | SU |
| Anoa, lowland | Bubalus depressicornis | - | Foreign | E |
| Anoa, mountain | Bubalus quarlesi | - | Foreign | E |
| Anobiid beetle, Piko | Holcobius pikoensis | - | 1 | SC |
| Anole, Cook's | Anolis cooki | - | 4 | SC |
| Anole, Culebra Island giant | Anolis roosevelti | - | 4 | E |
| Anole, Puerto Rican pygmy | Anolis occultus | - | 4 | SC |
| Ant, ancient | Smithistruma reliquia | - | 1 | SC |
| Ant, Charleston | Lasius nevadensis | - | 1 | SU |
| Ant, Valley oak | Proceratium californicum | - | 1 | UR |
| Ant, velvet | Dasymutilla imperialis | entire | 8 | RT |
| Ant, velvet | Dasymutilla nocturna | entire | 8 | RT |
| antelope Tibetan | Pantholops hodgsonii | entire | Foreign | E |
| Antelope, giant sable | Hippotragus niger variani | - | Foreign | E |
| Anthicid, Antioch Dunes | Anthicus antiochensis | - | 1 | SC |
| Anthicid, Sacramento | Anthicus sacramento | - | 1 | SC |
| Antlion, Molokai | Distoleon perjerus | - | 1 | SC |
| Antpitta, brown-banded | Grallaria milleri | - | Foreign | PE |
| Antwren, black hooded (black-headed) | Formicivora erythronotos | - | Foreign | PE |
| Apamea moth, Smyth's | Apamea smythi | - | 3 | SC |
| Aphanisma | Aphanisma blitoides | - | 1 | SC |
| Apoda | Pelea parvifolia apoda | - | 1 | RT |
| Arc-mussel, Altamaha | Alasmidonta arcula | - | 4 | SC |
| Arc-mussel, Florida | Alasmidonta wrightiana | - | 4 | SC |
| Argali | Ovis ammon | Kyrgyzstan, Mongolia, and Tajikistan | Foreign | T |
| Argali | Ovis ammon | Entire except Kyrgyzstan, Mongolia, and Tajikistan | Foreign | E |
| Armadillo, giant | Priodontes maximus | - | Foreign | E |
| Armadillo, pink fairy | Chlamyphorus truncatus | - | Foreign | E |
| Arnica, Shasta | Arnica viscosa | - | 1 | RT |
| Arrow-grass, Gaspe Peninsula | Triglochin gaspense | - | 5 | SC |
| Arrowhead, bunched | Sagittaria fasciculata | - | 4 | E |
| Arrowwood, [unnamed] | Viburnum bracteatum | - | 4 | SC |
| Artemisia, sp. nov. ined. | Artemisia sp. | - | 1 | RT |
| Ascyrum, Edison's | Hypericum edisonianum | - | 4 | SC |
| Ash, Goodding's | Fraxinus gooddingii | - | 2 | RT |
| Ash, large-petaled | Fraxinus cuspidata macropetala | - | 2 | RT |
| Ash, [unnamed] | Fraxinus anomala lowellii | - | 2 | RT |
| Asphodel, bog | Narthecium americanum | - | 5 | C |
| Ass, African wild | Equus asinus | - | Foreign | E |
| Ass, Asian wild | Equus hemionus | - | Foreign | E |
| Aster, Borrego | Xylorhiza orcuttii | - | 1 | SC |
| aster, Bouquet | eurybia mirabilis | - | 4 | SC |
| Aster, brikellbush | Aster brickellioides | - | 1 | RT |
| Aster, Chapman's | Aster chapmani | - | 4 | SC |
| Aster, Columbian whitetop | Sericocarpus rigidus | - | 1 | SC |
| Aster, coyote-thistle | Aster eryngiifolius | - | 4 | SC |
| Aster, Cruise's golden | Chrysopsis gossypina cruiseana | - | 4 | SC |
| Aster, curtus | Aster curtus | - | 1 | SC |
| Aster, decurrent false | Boltonia decurrens | - | 3 | T |
| Aster, Florida golden | Chrysopsis floridana | - | 4 | E |
| Aster, Georgia | Symphyotrichum georgianum | - | 4 | C |
| Aster, Godfrey's golden | Chrysopsis godfreyi | - | 4 | SC |
| Aster, Gorman | Aster gormanii | - | 1 | SC |
| Aster, Guadalupe smooth | Aster laevis guadalupensis | - | 2 | SC |
| Aster, Hawaiian | Aster sandwicensis | - | 1 | RT |
| Aster, Jessica's | Aster jessicae | - | 1 | SC |
| Aster, Laguna Mountains | Machaeranthera asteroides lagunensis | - | 1 | SC |
| Aster, Mecca | Xylorhiza cognata | - | 1 | SC |
| Aster, Peirson's | Aster peirsonii | - | 1 | RT |
| aster, Red Rock Canyon | ionactis caelestis | - | 6 | SC |
| Aster, Rockcastle | Aster saxicastellii | - | 4 | SC |
| Aster, rough-stemmed | Aster puniceus scabricaulis | - | 2 | SC |
| Aster, Ruth's golden | Pityopsis ruthii | - | 4 | E |
| Aster, serpentine | Aster depauperatus | - | 5 | SC |
| Aster, Suisun | Aster chilensis lentus | - | 1 | SC |
| Aster, wayside | Aster vialis | - | 1 | SC |
| Aster, western bog | Aster paludicola | - | 1 | RT |
| Aster, Yukon | Aster yukonensis | - | 7 | SC |
| Aster, Ziegler's | Machaeranthera canescens ziegleri | - | 1 | RT |
| Aster, [unnamed] | Aster brachypholis | - | 4 | RT |
| Aster, [unnamed] | Aster chasei | - | 3 | RT |
| Aster, [unnamed] | Aster furcatus | - | 3 | SC |
| Aster, [unnamed] | Aster glaucescens | - | 1 | RT |
| Aster, [unnamed] | Aster greatai | - | 1 | RT |
| Aster, [unnamed] | Aster hallii | - | 1 | RT |
| Aster, [unnamed] | Aster kingii kingii | - | 6 | RT |
| Aster, [unnamed] | Aster lemmonii | - | 2 | RT |
| Aster, [unnamed] | Aster mollis | - | 6 | SC |
| Aster, [unnamed] | Aster pinifolius | - | 4 | RT |
| Aster, [unnamed] | Aster plumosus | - | 4 | RT |
| Aster, [unnamed] | Aster schistosus | - | 5 | SC |
| Aster, [unnamed] | Aster spinulosus | - | 4 | SC |
| Aster, [unnamed] | Aster verutifolius | - | 4 | RT |
| Asteriid fly, Nihoa two-spotted | Bryania bipunctata | - | 1 | SC |
| Auklet, Cassin's | Ptychoramphus aleuticus | - | 1 | SC |
| aumakua, Palapalai | Dryopteris crinalis var. podosorus | - | 1 | E |
| Aupaka | Isodendrion hosakae | - | 1 | E |
| Aupaka | Isodendrion laurifolium | - | 1 | E |
| Aupaka | Isodendrion longifolium | - | 1 | T |
| Avahi | Avahi laniger (entire genus) | - | Foreign | E |
| Avens, bent | Geum geniculatum | - | 4 | SC |
| Avens, mountain | Geum peckii | - | 5 | RT |
| Avens, spreading | Geum radiatum | - | 4 | E |
| Awiwi | Centaurium sebaeoides | - | 1 | E |
| Awiwi | Hedyotis cookiana | - | 1 | E |
| Aye-aye | Daubentonia madagascariensis | - | Foreign | E |
| Ayenia, Texas | Ayenia limitaris | - | 2 | E |
| Ayumodoki (loach) | Hymenophysa curta | - | Foreign | E |
| Azalea, pink-shell | Rhododendron vaseyi | - | 4 | RT |
| Azalea, plumleaf | Rhododendron prunifolium | - | 4 | RT |
| A`e | Zanthoxylum dipetalum var. tomentosum | - | 1 | E |
| A`e | Zanthoxylum hawaiiense | - | 1 | E |
| A`e | Zanthoxylum oahuense | - | 1 | C |
| A`e | Zanthoxylum semiarticulatum | - | 1 | RT |
| A`e | Zanthoxylum skottsbergii | - | 1 | RT |
| Babirusa | Babyrousa babyrussa | - | Foreign | E |
| Baboon, gelada | Theropithecus gelada | - | Foreign | T |
| Baccharis, Encinitas | Baccharis vanessae | - | 8 | T |
| Bacora, marron | Solanum conocarpum | - | 4 | UR |
| badger, American | taxidiinae taxus | - | 2 | SC |
| Baeria, Salinas Valley | Lasthenia leptalea | - | 1 | RT |
| Ballmoss, Bailey's | Tillandsia baileyi | - | 2 | SC |
| balsamroot, Big scale | balsamorhiza macrolepis var. macrolepis | - | 6 | SC |
| Bandicoot, barred | Perameles bougainville | - | Foreign | E |
| Bandicoot, desert | Perameles eremiana | - | Foreign | E |
| Bandicoot, lesser rabbit | Macrotis leucura | - | Foreign | E |
| Bandicoot, pig-footed | Chaeropus ecaudatus | - | Foreign | E |
| Bandicoot, rabbit | Macrotis lagotis | - | Foreign | E |
| Bankclimber, purple (mussel) | Elliptoideus sloatianus | - | 4 | T |
| Banteng | Bos javanicus | - | Foreign | E |
| Barbara's buttons, large-flowered | Marshallia grandiflora | - | 5 | SC |
| Barberry, Hardy Creek | Berberis nervosa mendocinensis | - | 1 | SC |
| Barberry, Higgin's | Berberis higginsiae | - | 1 | RT |
| Barberry, island | Berberis pinnata ssp. insularis | - | 8 | E |
| Barberry, Kofa | Berberis harrisoniana | - | 2 | RT |
| Barberry, Nevin's | Berberis nevinii | - | 8 | E |
| Barberry, Truckee | Berberis (=Mahonia) sonnei | - | 8 | DO |
| Barberry, [unnamed] | Berberis swaseyi | - | 2 | RT |
| Barbthroat, black | Threnetes grzimeki | - | Foreign | UR |
| Bariaco | Trichilia triacantha | - | 4 | E |
| barley, Vernal | hordeum intercedens | - | 6 | SC |
| Barrel cactus, coast | Ferocactus viridescens | - | 1 | SC |
| barren strawberry, Piedmont | Waldsteinia lobata | - | 4 | RT |
| Bass, Guadalupe | Micropterus treculi | - | 2 | SC |
| Bat, Allen's big-eared | Idionycteris phyllotis | - | 6 | SC |
| bat, Big brown | eptesicus fuscus | - | 6 | SC |
| Bat, big free-tailed | Nyctinomops macrotis | - | 2 | SC |
| Bat, Bulmer's fruit (=flying fox) | Aproteles bulmerae | - | Foreign | E |
| Bat, bumblebee | Craseonycteris thonglongyai | - | Foreign | E |
| Bat, California leaf-nosed | Macrotus californicus | - | 2 | SC |
| Bat, Desmarest's fig-eating | Stenoderma rufum | - | 4 | SC |
| Bat, Eastern small-footed | Myotis leibii | - | 5 | SC |
| bat, Florida bonneted | Eumops floridanus | - | 4 | C |
| Bat, gray | Myotis grisescens | - | 3 | E |
| Bat, Hawaiian hoary | Lasiurus cinereus semotus | - | 1 | E |
| Bat, Indiana | Myotis sodalis | - | 3 | E |
| Bat, insular long-tongued | Monophylus plethodon frater | - | 4 | RT |
| Bat, lesser long-nosed | Leptonycteris curasoae yerbabuenae | - | 2 | E |
| Bat, little Mariana fruit | Pteropus tokudae | - | 1 | E |
| Bat, Mariana fruit (=Mariana flying fox) | Pteropus mariannus mariannus | entire range | 1 | T |
| Bat, Mexican long-nosed | Leptonycteris nivalis | - | 2 | E |
| Bat, Mexican long-tongued | Choeronycteris mexicana | - | 2 | SC |
| Bat, occult little brown | Myotis lucifugus occultus | - | 2 | SC |
| Bat, Ozark big-eared | Corynorhinus (=Plecotus) townsendii ingens | - | 2 | E |
| Bat, Pacific sheath-tailed | Emballonura semicaudata rotensis | - | 1 | C |
| Bat, Pacific sheath-tailed | Emballonura semicaudata semicaudata | American Samoa | 1 | C |
| Bat, Pacific Townsend's big-eared | Plecotus townsendii townsendii | - | 1 | SC |
| Bat, Pagan Mariana flying fox | Pteropus mariannus paganensis | - | 1 | SC |
| Bat, pale Townsend's big-eared | Plecotus townsendii pallescens | - | 2 | SC |
| bat, Pallid | antrozous pallidus | - | 2 | SC |
| bat, Pocketed free-tailed | nyctinomops femorosaccus | - | 6 | SC |
| Bat, Rafinesque's big-eared | Plecotus rafinesquii | - | 4 | SC |
| Bat, Rodrigues fruit (=flying fox) | Pteropus rodricensis | - | Foreign | E |
| Bat, Samoan fruit | Pteropus samoensis samoensis | - | 1 | UR |
| Bat, sheath-tailed | Emballonura semicaudata sulcata | - | 1 | SC |
| bat, Silver-haired | lasionycteris noctivagans | - | 7 | SC |
| Bat, Singapore roundleaf horseshoe | Hipposideros ridleyi | - | Foreign | E |
| bat, Southern yellow | Lasiurus ega | - | 8 | SC |
| Bat, spotted | Euderma maculatum | - | 2 | SC |
| bat, Townsend's western big-eared | plecotus townsendii ssp. pallescens | - | 6 | SC |
| bat, Townsend's western big-eared | plecotus townsendii ssp. townsendii | - | 6 | SC |
| Bat, Virginia big-eared | Corynorhinus (=Plecotus) townsendii virginianus | - | 5 | E |
| bat, Western red | lasiurus blossevillii | - | 6 | SC |
| Beaked-rush, California | Rhynchospora californica | - | 1 | SC |
| Beaked-rush, hairy-peduncled | Rhynchospora crinipes | - | 4 | SC |
| Beaked-rush, Knieskern's | Rhynchospora knieskernii | - | 5 | T |
| Beaked-rush, Thorne's | Rhynchospora thornei | - | 4 | SC |
| Beaked-rush, [unnamed] | Rhynchospora culixa | - | 4 | SC |
| Beaked-rush, [unnamed] | Rhynchospora decurrens | - | 4 | SC |
| Beaked-rush, [unnamed] | Rhynchospora globularis saxicola | - | 4 | RT |
| Beaked-rush, [unnamed] | Rhynchospora punctata | - | 4 | SC |
| Bean, Choctaw | Villosa choctawensis | - | 4 | C |
| Bean, Cumberland (pearlymussel) | Villosa trabalis | U.S.A. (TN - specified portions of the French Broad and Holston Rivers; see 17.85(b)(1)) | 4 | EXPN |
| Bean, Cumberland (pearlymussel) | Villosa trabalis | Entire Range; Except where listed as Experimental Populations | 4 | E |
| Bean, Cumberland (pearlymussel) | Villosa trabalis | U.S.A. (AL;The free-flowing reach of the Tennessee R. from the base of Wilson Dam downstream to the backwaters of Pickwick Reservoir [about 12 RM (19 km)] and the lower 5 RM [8 km] of all tributaries to this reach in Colbert and Lauderdale Cos., see 17.85(a)) | 4 | EXPN |
| Bean, purple | Villosa perpurpurea | - | 5 | E |
| Bean, rayed | Villosa fabalis | - | 3 | C |
| Bean, supine | Phaseolus supinus | - | 2 | SC |
| Bear, American black | Ursus americanus | PA population | 9 | SU |
| Bear, American black | Ursus americanus | White River Population | NA | SU |
| Bear, American black | Ursus americanus | U.S.A. (LA, all counties; MS, TX, only within the historic county range of the Louisiana black bear) | 4 | SAT |
| Bear, Baluchistan | Ursus thibetanus gedrosianus | - | Foreign | E |
| Bear, brown | Ursus arctos arctos | Kenai Peninsula Population | 7 | SC |
| Bear, brown | Ursus arctos arctos | Italy | Foreign | E |
| Bear, brown | Ursus arctos horribilis | Alaska | NA | SU |
| Bear, brown | Ursus arctos pruinosus | - | Foreign | E |
| Bear, Florida black | Ursus americanus floridanus | - | 4 | RT |
| Bear, Glacier | Ursus americanus emmonsii | - | 7 | RT |
| Bear, grizzly | Ursus arctos horribilis | North Cascades Ecosystem Recovery Zone Population | 6 | UR |
| Bear, grizzly | Ursus arctos horribilis | U.S.A. experimental non-essential (portions of ID and MT, see 17.84(l)) | 6 | EXPN |
| Bear, grizzly | Ursus arctos horribilis | Cabinet-Yaak Recovery Zone Population | 6 | UR |
| Bear, grizzly | Ursus arctos horribilis | U.S.A., conterminous (lower 48) States, except where listed as an experimental population or delisted | 6 | T |
| Bear, grizzly | Ursus arctos horribilis | Selkirk Recovery Zone Population | 6 | UR |
| Bear, Louisiana black | Ursus americanus luteolus | - | 4 | T |
| Bear, Mexican grizzly | Ursus arctos | Mexico | Foreign | E |
| Bear, polar | Ursus maritimus | - | 7 | T |
| Bear-poppy, dwarf | Arctomecon humilis | - | 6 | E |
| Beard grass, [unnamed] | Andropogon arctatus | - | 4 | RT |
| Beardtongue Ben Franklin's | Penstemon franklinii | - | 6 | SC |
| Beardtongue, Absaroka | Penstemon absarokensis | - | 6 | RT |
| Beardtongue, Alamo | Penstemon alamosensis | - | 2 | SC |
| Beardtongue, cache | Penstemon compactus | - | 6 | SC |
| Beardtongue, Cary | Penstemon caryi | - | 6 | SC |
| Beardtongue, Cataiina | Penstemon discolor | - | 2 | SC |
| beardtongue, Charleston | penstemon leiophyllus var. keckii | - | 6 | SC |
| Beardtongue, closed-lip | Penstemon personatus | - | 1 | SC |
| Beardtongue, Degener | Penstemon degeneri | - | 6 | RT |
| Beardtongue, Garrett's | Penstemon scariosus garrettii | - | 6 | RT |
| Beardtongue, Gibbens | Penstemon gibbensii | - | 6 | UR |
| Beardtongue, Graham | Penstemon grahamii | - | 6 | RT |
| Beardtongue, Harrington | Penstemon harringtonii | - | 6 | SC |
| Beardtongue, Lemhi | Penstemon lemhiensis | - | 1 | SC |
| Beardtongue, low | Penstemon nanus | - | 6 | SC |
| Beardtongue, Mt. Trumbull | Penstemon distans | - | 2 | SC |
| Beardtongue, Parachute | Penstemon debilis | - | 6 | PT |
| Beardtongue, Payson | Penstemon paysoniorum | - | 6 | RT |
| Beardtongue, Penland | Penstemon penlandii | - | 6 | E |
| Beardtongue, Red Canyon | Penstemon bracteatus | - | 6 | SC |
| Beardtongue, small | Penstemon parvus | - | 6 | SC |
| Beardtongue, stemless | Penstemon acaulis | - | 6 | SC |
| Beardtongue, Stephens' | Penstemon stephensii | - | 1 | SC |
| Beardtongue, Tidestrom | Penstemon tidestromii | - | 6 | SC |
| Beardtongue, tiger | Penstemon mensarum | - | 6 | SC |
| Beardtongue, Tracy | Penstemon tracyi | - | 1 | RT |
| Beardtongue, Tunnel Springs | Penstemon concinnus | - | 6 | SC |
| Beardtongue, Uintah | Penstemon uintahensis | - | 6 | RT |
| Beardtongue, Wallowa | Penstemon spatulatus | - | 1 | RT |
| Beardtongue, Ward | Penstemon wardii | - | 6 | SC |
| Beardtongue, White River | Penstemon scariosus albifluvis | - | 6 | C |
| Beardtongue, [unnamed] | Penstemon abietinus | - | 6 | RT |
| Beardtongue, [unnamed] | Penstemon angustifolius dulcis | - | 6 | SC |
| Beardtongue, [unnamed] | Penstemon caespitosus suffruticosus | - | 6 | RT |
| Beardtongue, [unnamed] | Penstemon clutei | - | 2 | SC |
| Beardtongue, [unnamed] | Penstemon deamii | - | 3 | SC |
| Beardtongue, [unnamed] | Penstemon decurvus | - | 1 | RT |
| Beardtongue, [unnamed] | Penstemon glaucinus | - | 1 | SC |
| Beardtongue, [unnamed] | Penstemon keckii | - | 1 | RT |
| Beardtongue, [unnamed] | Penstemon leiophyllus | - | 6 | RT |
| Beardtongue, [unnamed] | Penstemon nyeensis | - | 1 | RT |
| Beardtongue, [unnamed] | Penstemon pahutensis | - | 1 | SC |
| Beardtongue, [unnamed] | Penstemon pinorum | - | 6 | SC |
| Beardtongue, [unnamed] | Penstemon retrorsus | - | 6 | SC |
| Beardtongue, [unnamed] | Penstemon rubicundus | - | 1 | RT |
| Beargrass, Britton's | Nolina brittoniana | - | 4 | E |
| Beargrass, Dehesa | Nolina interrata | - | 1 | RT |
| beargrass, Peninsular | Nolina cismontana | - | 1 | SC |
| Beargrass, sp. nov. ined. (chaparral) | Nolina sp. | - | 1 | SC |
| Beargrass, [unnamed] | Nolina atopocarpa | - | 4 | SC |
| Beauty, Harper's | Harperocallis flava | - | 4 | E |
| Beaver (Mongolian) | Castor fiber birulai | - | Foreign | E |
| Beavertail cactus, short-jointed | Opuntia basilaris brachyclada | - | 1 | SC |
| Bedstraw, Borrego | Galium angustifolium borregoense | - | 1 | SC |
| Bedstraw, cliff | Galium correllii | - | 2 | SC |
| Bedstraw, Cone Peak | Galium californicum luciense | - | 1 | SC |
| Bedstraw, El Dorado | Galium californicum ssp. sierrae | - | 8 | E |
| Bedstraw, Hardham's | Galium hardhamiae | - | 1 | RT |
| Bedstraw, island | Galium buxifolium | - | 8 | E |
| Bedstraw, Kingston | Galium hilendiae kingstonense | - | 1 | SC |
| Bedstraw, Modoc | Galium glabrescens modocense | - | 1 | RT |
| Bedstraw, San Clemente island | Galium catalinense acrispum | - | 1 | SC |
| Bedstraw, San Gabriel | Galium grande | - | 1 | SC |
| Bedstraw, San Jacinto | Galium californicum primum | - | 1 | SC |
| bedstraw, San Jacinto Mountains | galium angustifolium ssp. jacinticum | - | 6 | SC |
| Bedstraw, San Miguel Island | Galium californicum miguelense | - | 1 | RT |
| Bedstraw, Santa Lucia | Galium clementis | - | 1 | RT |
| Bedstraw, Scott Mountains | Galium serpenticum scotticum | - | 1 | RT |
| Bedstraw, Telescope Peak | Galium hypotrichium tomentellum | - | 1 | RT |
| Bedstraw, Warner Mountains | Galium serpenticum warnerense | - | 1 | RT |
| Bedstraw, [unnamed] | Galium andrewsii gatense | - | 1 | RT |
| Bedstraw, [unnamed] | Galium collomae | - | 2 | RT |
| Bee, Andrenid | Perdita algondones | - | 1 | RT |
| Bee, Andrenid | Perdita glamis | entire | 8 | RT |
| Bee, Riverside cuckoo | Holcopasites ruthae | - | NA | RT |
| Beetle | Amblyderus werneri | - | 6 | SC |
| Beetle | Cyclocephala wandae | entire | 8 | RT |
| Beetle, American burying | Nicrophorus americanus | - | 2 | E |
| Beetle, bog idol leaf | Donacia idola | - | 1 | RT |
| Beetle, Channel Islands dune | Coelus pacificus | - | 1 | SC |
| Beetle, Coffin Cave mold | Batrisodes texanus | - | 2 | E |
| Beetle, Comal Springs dryopid | Stygoparnus comalensis | - | 2 | E |
| Beetle, Comal Springs riffle | Heterelmis comalensis | - | 2 | E |
| Beetle, Death Valley agabus diving | Agabus rumppi | - | 1 | UR |
| Beetle, delta green ground | Elaphrus viridis | - | 8 | T |
| Beetle, Duck River cave | Pseudanophthalmus tullahoma | - | 4 | RT |
| Beetle, globose dune | Coelus globosus | - | 1 | SC |
| Beetle, Hardy's dune | Anomala hardyorum | entire | 8 | RT |
| Beetle, Helotes mold | Batrisodes venyivi | - | 2 | E |
| Beetle, Hungerford's crawling water | Brychius hungerfordi | - | 3 | E |
| Beetle, Kretschmarr Cave mold | Texamaurops reddelli | - | 2 | E |
| Beetle, Mojave rabbitbrush longhorn | Crossidius mojavensis mojavensis | - | 1 | RT |
| Beetle, Mount Hermon June | Polyphylla barbata | - | 8 | E |
| Beetle, Nickajack Cave | Pseudanophthalmus nickajackensis | - | 4 | RT |
| Beetle, riffle | Microcylloepus sp | - | NA | SU |
| Beetle, Robinson's rain scarab | Phoebetus robinsoni | - | 1 | RT |
| Beetle, San Joaquin dune | Coelus gracilis | - | 1 | RT |
| Beetle, Santa Cruz rain | Pleocoma conjugens conjugens | - | 1 | RT |
| Beetle, seclusive water scavenger | Paracymus seclusus | - | 4 | RT |
| Beetle, Snail shell cave | Pseudanophthalmus acherontis | - | 4 | RT |
| Beetle, Tooth Cave blind rove | Cylindropsis sp. | - | 2 | RT |
| Beetle, Tooth Cave ground | Rhadine persephone | - | 2 | E |
| Beetle, valley elderberry longhorn | Desmocerus californicus dimorphus | - | 8 | T |
| Beetle, Warm Springs Zaitzevian riffle | Zaitzevia thermae | - | 6 | RT |
| Beetle, West Wills Valley cave | Pseudanophthalmus assimilis | - | 4 | SC |
| Bellflower, Basin | Campanula reverchonii | - | 2 | RT |
| Bellflower, Brooksville | Campanula robinsiae | - | 4 | E |
| Benitoa, western | Benitoa occidentalis | - | 1 | RT |
| Bensoniella | Bensoniella oregona | - | 1 | SC |
| Bentgrass, awned | Agrostis aristiglumis | - | 1 | RT |
| Bentgrass, Blasdale's | Agrostis blasdalei blasdalei | - | 1 | SC |
| Bentgrass, coastal bluff | Agrostis clivicola clivicola | - | 1 | RT |
| Bentgrass, Henderson's | Agrostis microphylla hendersonii | - | 1 | SC |
| Bentgrass, Howell's | Agrostis howellii | - | 1 | SC |
| Bentgrass, Marin | Agrostis blasdalei marinensis | - | 1 | RT |
| Bentgrass, Point Reyes | Agrostis clivicola punta-reyesensis | - | 1 | RT |
| Bentgrass, Ross | Agrostis rossiae | - | 6 | UR |
| Berry, wooly | Vaccinium hirsutum | - | 4 | SC |
| Bidens, campylotheca | Bidens campylotheca campylotheca | - | 1 | RT |
| Bidens, cuneate | Bidens cuneata | - | 1 | DR |
| Bidens, Forbes | Bidens forbesii | - | 1 | RT |
| Bidens, Manoa | Bidens coarctata | - | 1 | RT |
| Bidens, Maunalua | Bidens graciloides | - | 1 | RT |
| Bidens, poplar-leaved | Bidens populifolia | - | 1 | RT |
| Bidens, robust | Bidens valida | - | 1 | RT |
| Bidens, willow-leaved | Bidens salicoides | - | 1 | RT |
| Bilberry, Siskiyou Mountains | Vaccinium coccineum | - | 1 | RT |
| bindweed, Clay | convolvulus equitans | - | 6 | SC |
| Birch, Virginia round-leaf | Betula uber | - | 5 | T |
| Birch, [unnamed] | Betula murrayana | - | 3 | SC |
| Bird's beak, palmate-bracted | Cordylanthus palmatus | - | 8 | E |
| Bird's-beak, desert | Cordylanthus eremicus eremicus | - | 1 | RT |
| Bird's-beak, Fresno County | Cordylanthus tenuis barbatus | - | 1 | SC |
| Bird's-beak, hispid | Cordylanthus mollis hispidus | - | 1 | SC |
| Bird's-beak, Mt. Diablo | Cordylanthus nidularius | - | 8 | SC |
| Bird's-beak, northcoast | Cordylanthus maritimus palustris | - | 1 | SC |
| Bird's-beak, Orcutt's | Cordylanthus orcuttianus | - | 1 | SC |
| Bird's-beak, pallid | Cordylanthus tenuis pallescens | - | 1 | SC |
| Bird's-beak, Pennell's | Cordylanthus tenuis ssp. capillaris | - | 8 | E |
| Bird's-beak, salt marsh | Cordylanthus maritimus ssp. maritimus | - | 8 | E |
| Bird's-beak, San Bernardino | Cordylanthus eremicus bernardinus | - | 1 | RT |
| Bird's-beak, seaside | Cordylanthus rigidus littoralis | - | 1 | SC |
| Bird's-beak, soft | Cordylanthus mollis ssp. mollis | - | 8 | E |
| Bird's-beak, Tecopa | Cordylanthus tecopensis | - | 1 | SC |
| Birds-in-a-nest, Carolina | Macbridea caroliniana | - | 4 | SC |
| Birds-in-a-nest, white | Macbridea alba | - | 4 | T |
| Biscuitroot, Cedar Breaks | Cymopterus minimus | - | 6 | SC |
| Biscuitroot, Coulter | Cymopterus coulteri | - | 6 | RT |
| Biscuitroot, Duchesne | Cymopterus duchesnensis | - | 6 | RT |
| Biscuitroot, Higgins | Cymopterus acaulis higginsii | - | 6 | SC |
| Bison, plains | Bison bison bison | - | 6 | UR |
| Bison, wood | Bison bison athabascae | Canada | 7 | E |
| Bittercress, Constance's | Cardamine constancei | - | 1 | RT |
| Bittercress, Kona | Cardamine konaensis | - | 1 | RT |
| Bittercress, Long's | Cardamine longii | - | 5 | RT |
| Bittercress, mountain | Cardamine clematitis | - | 4 | SC |
| Bittercress, Saddle Mountain | Cardamine pattersonii | - | 1 | SC |
| Bittercress, small-anthered | Cardamine micranthera | - | 4 | E |
| Bittercress, [unnamed] | Cardamine rupicola | - | 6 | RT |
| bittern, American | botaurus lentiginosus | - | 7 | SC |
| Bittern, least | Ixobrychus exilis hesperis | - | 1 | SC |
| Bitterroot, Yosemite | Lewisia disepala | - | 1 | RT |
| Blackbird, grey-headed | Turdus poliocephalus poliocephalus | - | Foreign | UR |
| Blackbird, tricolored | Agelaius tricolor | - | 1 | RT |
| Blackbird, yellow-shouldered | Agelaius xanthomus | - | 4 | E |
| Bladder-pod, Bryce | Lesquerella rubicundula | - | 6 | RT |
| Bladder-pod, Duck River | Lesquerella densipila | - | 4 | RT |
| Bladder-pod, Fremont's | Lesquerella fremontii | - | 6 | RT |
| Bladder-pod, Garrett | Lesquerella garrettii | - | 6 | SC |
| Bladder-pod, golden | Lesquerella aurea | - | 2 | RT |
| Bladder-pod, Gooddings | Lesquerella gooddingii | - | 2 | RT |
| Bladder-pod, large-fruited | Lesquerella macrocarpa | - | 6 | SC |
| Bladder-pod, strong | Lesquerella valida | - | 2 | RT |
| Bladder-pod, thread-leaved | Lesquerella angustifolia | - | 2 | RT |
| Bladder-pod, [unnamed] | Lesquerella hitchcockii | - | 1 | RT |
| Bladder-pod, [unnamed] | Lesquerella kingii diversifolia | - | 1 | RT |
| Bladder-pod, [unnamed] | Lesquerella lata | - | 2 | RT |
| Bladder-pod, [unnamed] | Lesquerella lescurii | - | 4 | RT |
| Bladder-pod, [unnamed] | Lesquerella mcvaughiana | - | 2 | RT |
| Bladder-pod, [unnamed] | Lesquerella parviflora | - | 6 | RT |
| Bladder-pod, [unnamed] | Lesquerella pruinosa | - | 6 | SC |
| Bladderpod Pryor Mountains | Lesquerella lesicii | - | 6 | SC |
| Bladderpod, Dudley Bluffs | Lesquerella congesta | - | 6 | T |
| Bladderpod, Kaibab | Lesquerella kaibabensis | - | 2 | SC |
| Bladderpod, keeled | Lesquerella carinata | - | 6 | SC |
| Bladderpod, kodachrome | Lesquerella tumulosa | - | 6 | E |
| Bladderpod, lyrate | Lesquerella lyrata | - | 4 | T |
| Bladderpod, Missouri | Lesquerella filiformis | - | 3 | T |
| Bladderpod, San Bernardino Mountains | Lesquerella kingii ssp. bernardina | - | 8 | E |
| Bladderpod, Short's | Lesquerella globosa | - | 4 | C |
| Bladderpod, Spring Creek | Lesquerella perforata | - | 4 | E |
| Bladderpod, Stones River | Lesquerella stonensis | - | 4 | RT |
| Bladderpod, white | Lesquerella pallida | - | 2 | E |
| Bladderpod, White Bluffs | Physaria douglasii tuplashensis | - | 1 | C |
| Bladderpod, Zapata | Lesquerella thamnophila | - | 2 | E |
| Bladderpod, [unnamed] | Lesquerella humilis | - | 6 | SC |
| Bladderpod, [unnamed] | Lesquerella paysonii | - | 6 | SC |
| Blanketflower, white | Gaillardia aestivalis winkleri | - | 2 | SC |
| Blanketflower, yellow | Gaillardia flava | - | 6 | RT |
| Blazing-star, clay | Mentzelia argillosa | - | 6 | SC |
| Blazingstar Goodrich's | Mentzelia goodrichii | - | 6 | SC |
| Blazingstar, Ash Meadows | Mentzelia leucophylla | - | 8 | T |
| Blazingstar, Godfrey's | Liatris provincialis | - | 4 | SC |
| Blazingstar, Heller's | Liatris helleri | - | 4 | T |
| Blazingstar, scrub | Liatris ohlingerae | - | 4 | E |
| Blazingstar, [unnamed] | Liatris borealis | - | 5 | SC |
| Bleeding-heart, Pacific | Dicentra formosa oregana | - | 1 | RT |
| Bleeding-heart, Sierra Nevada | Dicentra nevadensis | - | 1 | RT |
| Bleedingheart, yellow | Dicentra ochroleuca | - | 1 | RT |
| Blindcat, Mexican (catfish) | Prietella phreatophila | - | Foreign | E |
| Blindcat, toothless | Trogloglanis pattersoni | - | 2 | RT |
| Blindcat, widemouth | Satan eurystomus | - | 2 | RT |
| Blister beetle, Anthony | Lytta mirifica | - | 2 | SC |
| Blister beetle, Hopping's | Lytta hoppingi | - | 1 | SC |
| Blister beetle, moestan | Lytta moesta | - | 1 | SC |
| Blister beetle, Mojave Desert | Lytta inseparata | - | 1 | SC |
| Blister beetle, molestan | Lytta molesta | - | 1 | SC |
| Blister beetle, Morrison's | Lytta morrisoni | - | 1 | SC |
| Blossom, green (pearlymussel) | Epioblasma torulosa gubernaculum | - | 4 | E |
| Blossom, tubercled (pearlymussel) | Epioblasma torulosa torulosa | Entire Range; Except where listed as Experimental Populations | 4 | E |
| Blossom, tubercled (pearlymussel) | Epioblasma torulosa torulosa | U.S.A. (AL;The free-flowing reach of the Tennessee R. from the base of Wilson Dam downstream to the backwaters of Pickwick Reservoir [about 12 RM (19 km)] and the lower 5 RM [8 km] of all tributaries to this reach in Colbert and Lauderdale Cos., see 17.85(a)) | 4 | EXPN |
| Blossom, turgid (pearlymussel) | Epioblasma turgidula | U.S.A. (AL;The free-flowing reach of the Tennessee R. from the base of Wilson Dam downstream to the backwaters of Pickwick Reservoir [about 12 RM (19 km)] and the lower 5 RM [8 km] of all tributaries to this reach in Colbert and Lauderdale Cos., see 17.85(a)) | 4 | EXPN |
| Blossom, turgid (pearlymussel) | Epioblasma turgidula | Entire Range; Except where listed as Experimental Populations | 4 | E |
| Blossom, yellow (pearlymussel) | Epioblasma florentina florentina | Entire Range; Except where listed as Experimental Populations | 4 | E |
| Blossom, yellow (pearlymussel) | Epioblasma florentina florentina | U.S.A. (AL;The free-flowing reach of the Tennessee R. from the base of Wilson Dam downstream to the backwaters of Pickwick Reservoir [about 12 RM (19 km)] and the lower 5 RM [8 km] of all tributaries to this reach in Colbert and Lauderdale Cos., see 17.85(a)) | 4 | EXPN |
| Blue curls, sp. nov. ined. | Trichostema sp. | - | 4 | SC |
| Blue, Baking Powder Flat | Euphilotes bernardino minuta | - | 8 | UR |
| Blue, Boharts' | Philotiella speciosa bohartorum | - | 1 | SC |
| Blue, dark | Euphilotes enoptes ssp. | - | 1 | SC |
| Blue, Mattoni's | Euphilotes rita mattoni | - | 1 | SC |
| Blue, Pheres | Icaricia icarioides pheres | - | 1 | RT |
| Blue, Point Reyes | Icaricia icariodes ssp. | - | 1 | SC |
| Blue, San Emigdio | Plebulina emigdionis | - | 1 | SC |
| Blue, San Gabriel Mountains | Plejebus saepiolus ssp. | San Gabriel Mts | 1 | SC |
| Blue, Sand Mountain | Euphilotes rita ssp. | - | 1 | SC |
| Blue, Spring Mountains | Plejebus shasta charlestonensis | - | 1 | SC |
| Blue, Spring Mountains icarioides | Plejebus icarioides ssp. | Spring Mts | 1 | SC |
| Blue, White Mountains icarioides | Plejebus icarioides ssp. | White Mts | 1 | SC |
| Blue, White Mountains saepiolus | Plejebus saepiolus ssp. | White Mts | 1 | SC |
| Blue, Xerces | Glaucopsyche xerces | - | 1 | RT |
| Blue-eyed grass, Mountain | Sisyrinchium sarmentosum | - | 1 | UR |
| Blue-star, Kearney's | Amsonia kearneyana | - | 2 | E |
| Blue-star, Louisiana | Amsonia ludoviciana | - | 4 | RT |
| Blue-star, smooth | Amsonia glaberrima | - | 2 | RT |
| Blue-star, Tharp | Amsonia tharpii | - | 2 | SC |
| Blue-star, [unnamed] | Amsonia grandiflora | - | 2 | SC |
| Blue-star, [unnamed] | Amsonia palmeri | - | 2 | RT |
| Blue-star, [unnamed] | Amsonia peeblesii | - | 2 | RT |
| Blue-star, [unnamed] | Amsonia repens | - | 2 | RT |
| Bluebell, Drummond | Mertensia drummondii | - | 7 | SC |
| Bluebells, canescent | Mertensia viridis cana | - | 6 | RT |
| Bluebells, smooth-leaf | Mertensia viridis dilatata | - | 6 | RT |
| Bluebells, [unnamed] | Mertensia toyabensis | - | 1 | RT |
| bluebird, Western | sialia mexicana | - | 2 | SC |
| Bluecup, Lake Alamanor | Githopsis latifolia | - | 1 | RT |
| Bluecup, Mission Canyon | Githopsis diffusa filicaulis | - | 1 | SC |
| Bluecurls, Hidden Lake | Trichostema austromontanum ssp. compactum | - | 8 | T |
| Bluegrass, Big Bend | Poa involuta | - | 2 | RT |
| Bluegrass, bog | Poa paludigena | - | 3 | SC |
| Bluegrass, Hawaiian | Poa sandvicensis | - | 1 | E |
| Bluegrass, Lassen County | Poa fibrata | - | 1 | RT |
| Bluegrass, Mann's | Poa mannii | - | 1 | E |
| Bluegrass, Napa | Poa napensis | - | 8 | E |
| Bluegrass, Piper's | Poa piperi | - | 1 | RT |
| Bluegrass, San Bernardino | Poa atropurpurea | - | 8 | E |
| Bluegrass, sea cliff | Poa unilateralis | - | 1 | RT |
| Bluegrass, timber | Poa rhizomata | - | 1 | RT |
| Bluegrass, [unnamed] | Poa strictiramea | - | 2 | SC |
| Bluet, Alpine | Houstonia caerulea faxonorum | - | 5 | RT |
| Bluet, lateral | Enallagma laterale | - | 5 | SC |
| Bluet, Roan Mountain | Hedyotis purpurea var. montana | - | 4 | E |
| Bluet, [unnamed] | Hedyotis butterwickiae | - | 2 | SC |
| Boa, coastal rosy | Lichanura trivirgata roseofusca | - | 1 | SC |
| Boa, Jamaican | Epicrates subflavus | - | Foreign | E |
| Boa, Mona | Epicrates monensis monensis | - | 4 | T |
| Boa, Navassa dusky dwarf | Tropidophis melanurus bucculentus | - | 4 | SC |
| Boa, Puerto Rican | Epicrates inornatus | - | 4 | E |
| Boa, rosy | Lichanura trivirgata | - | 2 | SC |
| Boa, Round Island bolyeria | Bolyeria multocarinata | - | Foreign | E |
| Boa, Round Island casarea | Casarea dussumieri | - | Foreign | E |
| Boa, southern rubber | Charina bottae umbratica | - | 1 | SC |
| Boa, Virgin Islands tree | Epicrates monensis granti | - | 4 | E |
| Bobcat | Lynx rufus | - | NA | RT |
| Bobcat, Mexican | Lynx (=Felis) rufus escuinapae | - | Foreign | E |
| Bobwhite, masked (quail) | Colinus virginianus ridgwayi | - | 2 | E |
| Bog-asphodel, smooth | Tofieldia glabra | - | 4 | SC |
| Bonamia, bigpod | Bonamia ovalifolia | - | 2 | SC |
| Bonamia, Florida | Bonamia grandiflora | - | 4 | T |
| Boneset, pine barrens | Eupatorium resinosum | - | 5 | SC |
| Bontebok | Damaliscus pygarus (=dorcas) dorcas | - | Foreign | E |
| Bonytongue, Asian | Scleropages formosus | - | Foreign | E |
| Booby, Abbott's | Papasula (=Sula) abbotti | - | Foreign | E |
| Bottlebrush grass, California | Elymus californicus | - | 1 | RT |
| Boxwood, Vahl's | Buxus vahlii | - | 4 | E |
| Brachymenium, Anderson's | Brachymenium andersonii | - | 4 | SC |
| Brasil, Edwards' | Condalia hookeri edwardsiana | - | 2 | SC |
| Braya, alpine | Braya humilis ventosa | - | 6 | RT |
| Brazos-mint, Centerville | Brazoria pulcherrima | - | 2 | RT |
| Brickell-bush, Florida | Brickellia mosieri | - | 4 | C |
| Brickell-bush, Flyr's | Brickellia cordifolia | - | 4 | SC |
| Brickellia, Knapp's | Brickellia knappiana | - | 1 | RT |
| Brickellia, Sierra Vieja | Brickellia viejensis | - | 2 | SC |
| Bricklebush, Hinckley's | Brickellia brachyphylla montanus | - | 1 | SC |
| Bricklebush, Terlingua | Brickellia brachyphylla terlinguensis | - | 2 | SC |
| Brine shrimp, Mono Lake | Artemia monica | - | 1 | SC |
| Bristle-moss, Keever's | Orthotrichum keeverae | - | 4 | SC |
| Bristlebird, western | Dasyornis longirostris (=brachypterus I.) | - | Foreign | E |
| Bristlebird, western rufous | Dasyornis broadbenti littoralis | - | Foreign | E |
| Bristlefront, Stresemann's | Merulaxis stresemanni | - | NA | SU |
| Bristlesnail, Trinity | Monadenia setosa | - | 1 | RT |
| Bristletail, Hawaiian long-palp | Neomachiloides heteropus | - | 1 | SC |
| Bristletail, Perkin's club-palp | Machiloides perkinsi | - | 1 | SC |
| Brittlescale | Atriplex depressa | - | 1 | SU |
| Brittlescale, Parrish's | Atriplex parishii | - | 1 | SC |
| Broadbill, Guam | Myiagra freycineti | - | 1 | D3A |
| Brodiaea, Chinese Camp | Brodiaea pallida | - | 8 | T |
| Brodiaea, Dudley's | Triteleia dudleyi | - | 1 | RT |
| Brodiaea, Indian Valley | Brodiaea coronaria rosea | - | 1 | SC |
| Brodiaea, Kaweah | Brodiaea insignis | - | 1 | SC |
| Brodiaea, Orcutt's | Brodiaea orcuttii | - | 1 | SC |
| Brodiaea, San Clemente Island | Brodiaea kinkiensis | - | 1 | SC |
| Brodiaea, San Clemente Island | Triteleia clementina | - | 1 | SC |
| Brodiaea, thread-leaved | Brodiaea filifolia | - | 8 | T |
| Brodiaea, vernal pool | Dichelostemma lacuna-vernalis | - | 1 | RT |
| Brome, Arizona | Bromus arizonicus | - | 1 | UR |
| Brongniartia, little-leaf | Brongniartia minutifolia | - | 2 | SC |
| Broom, San Clemente Island | Lotus dendroideus ssp. traskiae | - | 8 | E |
| Broomrape, Rock Creek | Orobanche valida valida | - | 1 | SC |
| Broomrape, short-lobed | Orobanche parishii brachyloba | - | 1 | SC |
| Browallia, sp. nov. ined. | Browallia sp. | - | 2 | SC |
| Buckmoth, [unnamed] | Hemileuca sp. | - | 5 | SC |
| Buckthorn, [unnamed] | Bumelia thornei | - | 4 | SC |
| Buckwheat Brandegee's Wild | Eriogonum brandegeei | - | 6 | UR |
| Buckwheat, Beatley | Eriogonum beatleyae | - | 1 | RT |
| Buckwheat, Butterworth's | Eriogonum butterworthianum | - | 1 | SC |
| Buckwheat, Cache Peak | Eriogonum kennedyi pinicola | - | 1 | SC |
| Buckwheat, Churchill Narrows | Eriogonum diatomaceum | - | 8 | C |
| Buckwheat, Clark Mountain | Eriogonum heermannii floccosum | - | 1 | RT |
| Buckwheat, Conejo | Eriogonum crocatum | - | 1 | SC |
| Buckwheat, Congdon's | Eriogonum congdonii | - | 1 | RT |
| Buckwheat, Contra Costa | Eriogonum truncatum | - | 8 | RT |
| Buckwheat, cottony | Eriogonum gossypinum | - | 1 | RT |
| Buckwheat, Crosby's | Eriogonum crosbyae | - | 1 | RT |
| Buckwheat, cushenbury | Eriogonum ovalifolium var. vineum | - | 8 | E |
| Buckwheat, Cusick's | Eriogonum cusickii | - | 1 | SC |
| Buckwheat, Donner Pass | Eriogonum umbellatum torreyanum | - | 1 | SC |
| Buckwheat, Dubakella Mountain | Eriogonum libertini | - | 1 | RT |
| Buckwheat, Eastwood's | Eriogonum eastwoodianum | - | 1 | RT |
| Buckwheat, forked | Eriogonum bifurcatum | - | 8 | SC |
| Buckwheat, Gilman's | Eriogonum gilmanii | - | 1 | RT |
| Buckwheat, golden | Eriogonum chrysops | - | 1 | SC |
| Buckwheat, Hoffmann's | Eriogonum hoffmannii hoffmannii | - | 1 | RT |
| Buckwheat, Holmgren's | Eriogonum holmgrenii | - | 1 | SC |
| Buckwheat, Idria | Eriogonum vestitum | - | 1 | RT |
| Buckwheat, Ione (incl. Irish Hill) | Eriogonum apricum (incl. var. prostratum) | - | 8 | E |
| Buckwheat, Jaynes Canyon | Eriogonum diclinum | - | 1 | RT |
| Buckwheat, Johnston's | Eriogonum microthecum johnstonii | - | 1 | SC |
| Buckwheat, jointed | Eriogonum intrafractum | - | 1 | SC |
| Buckwheat, Klamath Mountain | Eriogonum hirtellum | - | 1 | RT |
| Buckwheat, large red | Eriogonum grande rubescens | - | 1 | SC |
| buckwheat, Las Vegas | Eriogonum corymbosum var. nilesii | - | 8 | C |
| Buckwheat, Mono | Eriogonum ampullaceum | - | 1 | RT |
| Buckwheat, mouse | Eriogonum nudum murinum | - | 1 | SC |
| Buckwheat, Mt. Eddy | Eriogonum umbellatum humistratum | - | 1 | RT |
| Buckwheat, Olanche Peak | Eriogonum wrightii olanchense | - | 1 | RT |
| Buckwheat, Panamint Mountains | Eriogonum microthecum panamintense | - | 1 | SC |
| Buckwheat, Pinnacles | Eriogonum nortonii | - | 1 | RT |
| Buckwheat, Piute | Eriogonum breedlovei breedlovei | - | 1 | SC |
| Buckwheat, Point Lobos | Eriogonum parvifolium lucidum | - | 1 | RT |
| Buckwheat, prostrate | Eriogonum prociduum | - | 1 | SC |
| Buckwheat, Red Mountain | Eriogonum kelloggii | - | 8 | C |
| Buckwheat, Reveal's | Eriogonum contiguum | - | 1 | RT |
| Buckwheat, robust Hoffmann's | Eriogonum hoffmannii robustius | - | 1 | RT |
| Buckwheat, San Clemente Island | Eriogonum giganteum formosum | - | 1 | SC |
| Buckwheat, San Miguel Island | Eriogonum grande dunklei | - | 1 | RT |
| Buckwheat, San Nicolas Island | Eriogonum grande timorum | - | 1 | SC |
| Buckwheat, Santa Barbara Island | Eriogonum giganteum compactum | - | 1 | SC |
| Buckwheat, Santa Paula | Eriogonum parvifolium paynei | - | 1 | RT |
| Buckwheat, scrub | Eriogonum longifolium var. gnaphalifolium | - | 4 | T |
| Buckwheat, Siskiyou | Eriogonum siskiyouense | - | 1 | RT |
| Buckwheat, Snow Mountain | Eriogonum nervulosum | - | 1 | SC |
| Buckwheat, steamboat | Eriogonum ovalifolium var. williamsiae | - | 8 | E |
| Buckwheat, sulfur-flowered, alpine | Eriogonum umbellatum minus | - | 1 | RT |
| Buckwheat, Sulphur Springs | Eriogonum argophyllum | - | 8 | RT |
| Buckwheat, Temblor | Eriogonum temblorense | - | 1 | SC |
| Buckwheat, The Needles | Eriogonum breedlovei shevockii | - | 1 | RT |
| Buckwheat, Thorne's | Eriogonum ericifolium thornei | - | 1 | SC |
| Buckwheat, Tiburon | Eriogonum caninum | - | 1 | RT |
| Buckwheat, Tiehm's | Eriogonum tiehmii | - | 1 | SC |
| Buckwheat, Trinity | Eriogonum alpinum | - | 1 | SC |
| Buckwheat, Twisselmann's | Eriogonum twisselmannii | - | 1 | SC |
| Buckwheat, Umtanum Desert | Eriogonum codium | - | 1 | C |
| Buckwheat, Waldo | Eriogonum pendulum | - | 1 | RT |
| Buckwheat, Wild Rose Canyon | Eriogonum eremicola | - | 1 | SC |
| Buckwheat, [unnamed] | Eriogonum anemophilum | - | 1 | SC |
| Buckwheat, [unnamed] | Eriogonum lemmonii | - | 1 | RT |
| Buckwheat, [unnamed] | Eriogonum meledonum | - | 1 | SC |
| Buckwheat, [unnamed] | Eriogonum viscidulum | - | 8 | SC |
| Bug, Aaa water treader | Cavaticovelia aaa | - | 1 | SC |
| Bug, annectans rhopalid | Ithamar annectans | - | 1 | SC |
| Bug, Belfragi's chlorochroan | Chlorochroa belfragi | - | 3 | SC |
| Bug, Dismal Swamp chlorochroan | Chlorochroa dismalia | - | 5 | SC |
| Bug, Dry Creek cliff strider | Oravelia pege | - | 1 | SC |
| Bug, Hawaiian rhopalid | Ithamar hawaiiense | - | 1 | SC |
| Bug, Lanai kalanian leaf | Kalania hawaiiensis | - | 1 | SC |
| Bug, Oahu kalanian leaf | Kalania sp. | - | 1 | SC |
| Bug, phyllostegian leaf | Cyrtopeltis phyllostegiae | - | 1 | RT |
| Bug, Santa Rita Mountains chlorochroan | Chlorochroa rita | - | 2 | SC |
| Bug, Saratoga Springs belostoman | Belostoma saratogae | - | 1 | SC |
| Bug, Wekiu | Nysius wekiuicola | - | 1 | C |
| Bug, Wilbur Springs shore | Saldula usingeri | - | 1 | RT |
| Bugbane, Arizona | Cimicifuga arizonica | - | 2 | RT |
| Bugbane, Tall | Cimicifuga elata | - | 1 | SC |
| Bugseed Boat-shaped | Corispermum navicula | - | 6 | UR |
| Bulbul, Mauritius olivaceous | Hypsipetes borbonicus olivaceus | - | Foreign | E |
| Bullfinch, Sao Miguel (finch) | Pyrrhula pyrrhula murina | - | Foreign | E |
| Bullrush, [unnamed] | Scirpus hallii | - | 3 | SC |
| Bully, Everglades | Sideroxylon reclinatum ssp. austrofloridense | - | 4 | C |
| Bully, Everglades | Sideroxylon reclinatum var. austrofloridense | - | 4 | SU |
| Bulrush, Long's | Scirpus longii | - | 5 | SC |
| Bulrush, Northeastern | Scirpus ancistrochaetus | - | 5 | E |
| Bulrush, reclining | Scirpus flaccidifolius | - | 4 | SC |
| Bumblebee, Franklin's | Bombus franklini | - | 1 | SC |
| Bundleflower, ruby | Desmanthus bicornutus | - | 2 | RT |
| Bunting, eastern painted | Passerina ciris ciris | - | 4 | SC |
| Bunting, McKay's | Plectrophenax hyperboreus | - | 7 | SU |
| Bur-marigold, Maryland | Bidens bidentoides mariana | - | 5 | SC |
| Bur-marigold, [unnamed] | Bidens bidentoides bidentoides | - | 5 | SC |
| Burbot, Kootenai River | Lota lota | - | 1 | UR |
| Bush lupine, Mountains Springs | Lupinus excubitus medius | - | 1 | SC |
| bush mallow, Arcuate | malacothamnus arcuatus | - | 6 | SC |
| Bush monkeyflower, low | Diplacus aridus | - | 1 | RT |
| Bush-clover, prairie | Lespedeza leptostachya | - | 3 | T |
| Bush-mallow, Abbott's | Malacothamnus abbottii | - | 1 | SC |
| Bush-mallow, Arroyo Seco | Malacothamnus palmeri lucianus | - | 1 | SC |
| Bush-mallow, Carmel Valley | Malacothamnus palmeri involucratus | - | 1 | SC |
| Bush-mallow, Davidson's | Malacothamnus davidsonii | - | 1 | SC |
| Bush-mallow, Mendocino | Malacothamnus mendocinensis | - | 1 | SC |
| Bush-mallow, Palmer's | Malacothamnus palmeri palmeri | - | 1 | RT |
| Bush-mallow, Parish's | Malacothamnus parishii | - | 1 | SC |
| Bush-mallow, San Clemente Island | Malacothamnus clementinus | - | 8 | E |
| Bush-mallow, Santa Cruz Island | Malacothamnus fasciculatus var. nesioticus | - | 8 | E |
| Bush-pea, [unnamed] | Genistidium dumosum | - | 2 | SC |
| Bush-shrike, Ulugura | Malaconotus alius | - | Foreign | T |
| Bushwren, New Zealand | Xenicus longipes | - | Foreign | E |
| Bustard, great Indian | Ardeotis (=Choriotis) nigriceps | - | Foreign | E |
| Bustard, long-legged | Sypheotides indica | - | NA | SU |
| Buttercup, autumn | Ranunculus aestivalis (=acriformis) | - | 6 | E |
| Buttercup, Bladen | Ranunculus subcordatus | - | 4 | RT |
| Buttercup, [unnamed] | Ranunculus inamoenus subaffinis | - | 2 | RT |
| Butterfly plant, Colorado | Gaura neomexicana var. coloradensis | - | 6 | T |
| Butterfly, alamosa satyr | Cercyonis meadi alamosa | - | 6 | RT |
| Butterfly, Andrew's marble | Euchloe hyantis andrewsi | - | 1 | SC |
| Butterfly, Apache silverspot | Speyeria nokomis apacheana | - | 1 | RT |
| Butterfly, Bahama swallowtail | Heraclides andraemon bonhotei | - | 4 | DA |
| Butterfly, Bartram's hairstreak | Strymon acis bartrami | - | 4 | C |
| Butterfly, bay checkerspot | Euphydryas editha bayensis | - | 8 | T |
| Butterfly, Behren's silverspot | Speyeria zerene behrensii | - | 8 | E |
| Butterfly, blueblack silverspot | Speyeria nokomis nigrocaerulea | - | 2 | RT |
| Butterfly, bog elfin | Incisalia lanoraieensis | - | 5 | RT |
| Butterfly, callippe silverspot | Speyeria callippe callippe | - | 8 | E |
| Butterfly, Catalina orange tip | Anthocharis cethura catalina | - | 1 | RT |
| Butterfly, chryxus arctic | Oeneis chryxus valerata | - | 1 | RT |
| Butterfly, Clemence's fritillary | Speyeria adiaste clemencei | - | 1 | RT |
| Butterfly, clouded tailed copper | Lycaena arota nubila | - | 1 | RT |
| Butterfly, Comstock's blue | Euphilotes battoides comstocki | - | 1 | RT |
| Butterfly, Corsican swallowtail | Papilio hospiton | - | Foreign | E |
| Butterfly, Doudoroff's elfin | Incisalia mossi windi | - | 1 | RT |
| Butterfly, El Segundo blue | Euphilotes battoides allyni | - | 8 | E |
| Butterfly, Esperanza swallowtail | Papilio esperanza | - | NA | UR |
| Butterfly, Fender's blue | Icaricia icarioides fenderi | - | 1 | E |
| Butterfly, Florida atala | Eumaeus atala florida | - | 4 | SC |
| Butterfly, Florida leafwing | Anaea troglodyta floridalis | - | 4 | C |
| Butterfly, Fluminense swallowtail | Parides ascanius | - | Foreign | UR |
| Butterfly, Hahnel's Amazonian swallowtail | Parides hahneli | - | Foreign | UR |
| Butterfly, Harris' mimic swallowtail | Eurytides lysithous harrisianus | - | Foreign | UR |
| Butterfly, Hawaiian hairstreak | Vaga blackburni | - | 1 | RT |
| Butterfly, helios yellow | Eurema dina helios | - | 4 | RT |
| Butterfly, Hessel's hairstreak | Mitoura hesseli | - | 5 | RT |
| Butterfly, Homerus swallowtail | Papilio homerus | - | Foreign | E |
| Butterfly, Hydaspe fritillary | Speyeria hydaspe conquista | - | 6 | RT |
| Butterfly, Island large marble | Euchloe ausonides insulanus | - | 1 | RT |
| Butterfly, Jamaican kite swallowtail | Eurytides marcellinus | - | Foreign | UR |
| Butterfly, Kaiser-I-Hind swallowtail | Teinopalpus imperialis | - | Foreign | UR |
| Butterfly, Karner blue | Lycaeides melissa samuelis | - | 3 | E |
| Butterfly, Kendall's yucca skipper | Megathymus coloradensis kendalli | - | 2 | RT |
| Butterfly, Lange's metalmark | Apodemia mormo langei | - | 8 | E |
| Butterfly, Langston's blue | Euphilotes enoptes langstoni | - | 1 | RT |
| Butterfly, lotis blue | Lycaeides argyrognomon lotis | - | 8 | E |
| Butterfly, Luzon peacock swallowtail | Papilio chikae | - | Foreign | E |
| Butterfly, Mariana eight-spot | Hypolimnas octucula mariannensis | - | 1 | C |
| Butterfly, Mariana wandering | Vagrans egistina | - | 1 | C |
| Butterfly, Marianas euploea | Euploea eleutho | - | 1 | RT |
| Butterfly, Miami Blue | Cyclargus (=Hemiargus) thomasi bethunebakeri | - | 4 | C |
| Butterfly, minute checkerspot | Poladryas minuta minuta | - | 2 | RT |
| Butterfly, mission blue | Icaricia icarioides missionensis | - | 8 | E |
| Butterfly, Mitchell's satyr | Neonympha mitchellii mitchellii | - | 3 | E |
| butterfly, Morro Bay blue | Icaricia icarioides moroensis | - | 1 | SC |
| Butterfly, Mount Charleston blue | Icaricia shasta charlestonensis | - | 1 | UR |
| Butterfly, mountain silverspot | Speyeria nokomis nitocris | - | 2 | RT |
| Butterfly, Myrtle's silverspot | Speyeria zerene myrtleae | - | 8 | E |
| Butterfly, New Guinea birdwing | Ornithoptera meridionalis | - | NA | UR |
| Butterfly, obsolete viceroy | Limenitis archippus obsoletus | - | 1 | RT |
| Butterfly, Oregon silverspot | Speyeria zerene hippolyta | - | 1 | T |
| Butterfly, Oso Flaco patch | Chlosyne leanira osoflaco | - | 1 | SC |
| Butterfly, Palos Verdes blue | Glaucopsyche lygdamus palosverdesensis | - | 8 | E |
| Butterfly, Puerto Rico harlequin | Atlantea tulita | - | 4 | UR |
| Butterfly, Queen Alexandra's birdwing | Troides (=Omithoptara) alexandrae | - | Foreign | E |
| Butterfly, Quino checkerspot | Euphydryas editha quino (=E. e. wrighti) | - | 8 | E |
| Butterfly, Sacramento Mountains checkerspot | Euphydryas anicia cloudcrofti | - | 2 | RT |
| Butterfly, Saint Francis' satyr | Neonympha mitchellii francisci | - | 4 | E |
| Butterfly, San Bruno elfin | Callophrys mossii bayensis | - | 8 | E |
| Butterfly, Sand Mountain blue | Euphilotes pallescens arenamontana | entire | 8 | RT |
| Butterfly, Schaus swallowtail | Heraclides aristodemus ponceanus | - | 4 | E |
| Butterfly, Smith's blue | Euphilotes enoptes smithi | - | 8 | E |
| Butterfly, smoky eyed brown | Satyrodes eurydice fumosa | - | 6 | RT |
| Butterfly, Spring Mountains acastus checkerspot | Chlosyne acastus robusta | - | 8 | UR |
| butterfly, Spring Mountains comma skipper | hesperia comma ssp. mojavensis | - | 2 | SC |
| Butterfly, swallowtail | Battus zetides | - | NA | SU |
| Butterfly, swallowtail | Eurytides iphitas | - | NA | SU |
| Butterfly, swallowtail | Graphium levassori | - | NA | SU |
| Butterfly, swallowtail | Graphium sandawanum | - | NA | SU |
| Butterfly, swallowtail | Papilio benguetanus | - | NA | SU |
| Butterfly, swallowtail | Papilio carolinensis | - | NA | SU |
| Butterfly, swallowtail | Papilio desmondi teita | - | NA | SU |
| Butterfly, swallowtail | Papilio himeros | - | NA | SU |
| Butterfly, swallowtail | Papilio leucotaenia | - | NA | SU |
| Butterfly, swallowtail | Papilio maraho | - | NA | SU |
| Butterfly, swallowtail | Papilio moerneri | - | NA | SU |
| Butterfly, swallowtail | Papilio morondavana | - | NA | SU |
| Butterfly, swallowtail | Papilio neumoegeni | - | NA | SU |
| Butterfly, swallowtail | Papilio osmana | - | NA | SU |
| Butterfly, swallowtail | Papilio phorbanta | - | NA | SU |
| Butterfly, swallowtail | Parides burchellanus | - | NA | SU |
| Butterfly, swallowtail | Parides jophon | - | NA | SU |
| Butterfly, swallowtail | Parides schadenberqi | - | NA | SU |
| Butterfly, swallowtail | Troides croesus | - | NA | SU |
| Butterfly, swallowtail | Troides dohertyi | - | NA | SU |
| Butterfly, Uncompahgre fritillary | Boloria acrocnema | - | 6 | E |
| Butterfly, Wind's elfin | Incisalia mossi doudoroffi | - | 1 | RT |
| Butterfly-pea, [unnamed] | Centrosema arenicola | - | 4 | RT |
| Butternut | Juglans cinerea | - | 4 | SC |
| Butterweed, Gander | Senecio ganderi | - | 1 | SC |
| Butterweed, Layne's | Senecio layneae | - | 8 | T |
| Butterweed, Red Hills | Senecio clevelandii heterophyllus | - | 1 | RT |
| Butterweed, San Bernardino | Senecio bernardinus | - | 1 | SC |
| Butterwort, Chapman's | Pinguicula planifolia | - | 4 | SC |
| Butterwort, Godfrey's | Pinguicula ionantha | - | 4 | T |
| Button cactus, Boke's | Epithelantha bokei | - | 2 | RT |
| Button, Mohr's Barbara | Marshallia mohrii | - | 4 | T |
| Button-celery, Hoover's | Eryngium aristulatum hooveri | - | 1 | SC |
| Button-celery, San Diego | Eryngium aristulatum var. parishii | - | 8 | E |
| Button-clery, Pendleton | Eryngium pendletonensis | - | 1 | SU |
| Buttons, tiny bog | Lachnocaulon digynum | - | 4 | SC |
| Cactus, Acuna | Echinomastus erectocentrus var. acunensis | - | 2 | C |
| Cactus, Arizona hedgehog | Echinocereus triglochidiatus var. arizonicus | - | 2 | E |
| Cactus, Bakersfield | Opuntia treleasei | - | 8 | E |
| Cactus, black lace | Echinocereus reichenbachii var. albertii | - | 2 | E |
| Cactus, Brady pincushion | Pediocactus bradyi | - | 2 | E |
| Cactus, butterfly, Gaut's | Neolloydia gautii | - | 2 | RT |
| Cactus, Chisos Mountain hedgehog | Echinocereus chisoensis var. chisoensis | - | 2 | T |
| Cactus, Cochise pincushion | Coryphantha robbinsorum | - | 2 | T |
| Cactus, Colorado hookless | Sclerocactus glaucus | - | 6 | T |
| Cactus, Fickeisen plains | Pediocactus peeblesianus fickeiseniae | - | 2 | C |
| Cactus, Florida semaphore | Consolea corallicola | - | 4 | C |
| cactus, Foxtail | escobaria alversonii | - | 6 | SC |
| Cactus, Hoffmann's | Opuntia bigelovii hoffmannii | - | 1 | RT |
| Cactus, Kaibab plains | Pediocactus paradinei | - | 2 | RT |
| Cactus, Key tree | Pilosocereus robinii | - | 4 | E |
| Cactus, Knowlton | Pediocactus knowltonii | - | 2 | E |
| Cactus, Kuenzler hedgehog | Echinocereus fendleri var. kuenzleri | - | 2 | E |
| Cactus, Lee pincushion | Coryphantha sneedii var. leei | - | 2 | T |
| Cactus, Lloyd's hedgehog | Echinocereus lloydii | - | 2 | DO |
| Cactus, Lloyd's Mariposa | Echinomastus mariposensis | - | 2 | T |
| Cactus, Mesa Verde | Sclerocactus mesae-verdae | - | 2 | T |
| Cactus, Nellie cory | Coryphantha minima | - | 2 | E |
| Cactus, Nichol's Turk's head | Echinocactus horizonthalonius var. nicholii | - | 2 | E |
| Cactus, paper-spined | Pediocactus papyracanthus | - | 2 | SC |
| cactus, Pariette | Sclerocactus brevispinus | - | 6 | T |
| Cactus, Peebles Navajo | Pediocactus peeblesianus var. peeblesianus | - | 2 | E |
| Cactus, Pima pineapple | Coryphantha scheeri var. robustispina | - | 2 | E |
| Cactus, San Rafael | Pediocactus despainii | - | 6 | E |
| Cactus, Santa Cruz beehive | Coryphantha recurvata | - | 2 | SC |
| Cactus, Siler pincushion | Pediocactus (=Echinocactus,=Utahia) sileri | - | 2 | T |
| Cactus, Sneed pincushion | Coryphantha sneedii var. sneedii | - | 2 | E |
| Cactus, spineless hedgehog | Echinocereus triglochidiatus var. inermis | - | 6 | DO |
| Cactus, star | Astrophytum asterias | - | 2 | E |
| Cactus, Tobusch fishhook | Ancistrocactus tobuschii | - | 2 | E |
| cactus, Uinta Basin hookless | Sclerocactus wetlandicus | - | 6 | T |
| Cactus, Winkler | Pediocactus winkleri | - | 6 | T |
| Cactus, Wright fishhook | Sclerocactus wrightiae | - | 6 | E |
| Caddisfly, Abellan hydropsyche | Hydropsyche abella | - | 1 | SC |
| Caddisfly, Alexander's rhyacophilan | Rhyacophila alexanderi | - | 6 | SC |
| Caddisfly, amphibious | Desmona bethula | - | 1 | SC |
| Caddisfly, Arkansas agapetus | Agapetus medicus | - | 4 | SC |
| Caddisfly, artesian agapetus | Agapetus artesus | - | 3 | SC |
| Caddisfly, Athens long-horned | Triaenodes phalacris | - | 3 | RT |
| Caddisfly, Balmorhea saddle-case | Protoptila balmorhea | - | 2 | SC |
| Caddisfly, Bilobed rhyacophilan | Rhyacophila mosana | - | 1 | SC |
| Caddisfly, Blue Mountains cryptochian | Cryptochia neosa | - | 1 | SC |
| Caddisfly, Buffalo Springs | Ceratopsyche etnieri | - | 4 | SC |
| Caddisfly, Cahaba saddle-case | Protoptila cahabensis | - | 4 | SC |
| Caddisfly, California diplectronan | Diplectrona californica | - | 1 | SC |
| Caddisfly, Carlson's polycentropus | Polycentropus carlsoni | - | 4 | SC |
| Caddisfly, Cascades apatanian | Apatania tavala | - | 1 | SC |
| Caddisfly, Castle Crags rhyacophilan | Rhyacophila lineata | - | 1 | SC |
| Caddisfly, Castle Lake rhyacophilan | Rhyacophila amabilis | - | 1 | RT |
| Caddisfly, Clatsop philocascan | Philocasca oron | - | 1 | SC |
| Caddisfly, Cold Spring | Lepidostoma ermanae | - | 1 | SC |
| Caddisfly, Columbia Gorge neothremman | Neothremma andersoni | - | 1 | SC |
| Caddisfly, confusion | Cryptochia shasta | - | 1 | SC |
| Caddisfly, Denning's agapetus | Agapetus denningi | - | 1 | SC |
| Caddisfly, Denning's cryptic | Cryptochia denningi | - | 1 | SC |
| Caddisfly, Fender's rhyacophilan | Rhyacophila fenderi | - | 1 | RT |
| Caddisfly, Fischer's lelpidostoman | Lepidostoma fischeri | - | 1 | RT |
| Caddisfly, Flint's net-spinning | Cheumatopsyche flinti | - | 2 | RT |
| Caddisfly, Florida ceraclean longhorn | Ceraclea floridana | - | 4 | SC |
| Caddisfly, Fort Dick limnephilus | Limnephilus atercus | - | 1 | SC |
| Caddisfly, Goeden's lepidostoman | Lepidostoma goedeni | - | 1 | SC |
| Caddisfly, golden-horned | Neothremma genella | - | 1 | SC |
| Caddisfly, Green Springs Mountain farulan | Farula davisi | - | 1 | SC |
| Caddisfly, Haddock's rhyacophilan | Rhyacophila haddocki | - | 1 | SC |
| Caddisfly, headwater chilostigman | Chilostigma itascae | - | 3 | SC |
| Caddisfly, Helma's net-spinning | Cheumatopsyche helma | - | 5 | SC |
| Caddisfly, King's Creek ecclisomyian | Ecclisomyia bilera | - | 1 | SC |
| Caddisfly, King's Creek parapsyche | Parapsyche extensa | - | 1 | SC |
| Caddisfly, Kings Canyon cryptochian | Cryptochia excella | - | 1 | SC |
| Caddisfly, Klamath limnephilan | Limnephilus alconura | - | 1 | RT |
| Caddisfly, Lenat's ceraclean | Ceraclea sp. | - | 4 | SC |
| Caddisfly, little oecetis longhorn | Oecetis parva | - | 4 | SC |
| Caddisfly, long-tailed | Farula sp. | - | 1 | SC |
| Caddisfly, Missouri glyphopsyche | Glyphopsyche missouri | - | 3 | SC |
| Caddisfly, Morse's net-spinning | Cheumatopsyche morsei | - | 4 | SC |
| Caddisfly, Mt. Hood farulan | Farula jewetti | - | 1 | SC |
| Caddisfly, Mt. Hood primitive brachycentrid | Eobrachycentrus gelidae | - | 1 | SC |
| Caddisfly, nearctic paduniellan | Paduniella nearctica | - | 4 | SC |
| Caddisfly, Obrien rhyacophilan | Rhyacophila colonus | - | 1 | SC |
| Caddisfly, one-spot rhyacophilan | Rhyacophila unipunctata | - | 1 | SC |
| Caddisfly, Oregon dolophilodes | Dolophilodes oregona | - | 1 | RT |
| Caddisfly, Reisen's hydropsyche | Hydropsyche reiseni | - | 2 | SC |
| Caddisfly, Sagehen Creek goeracean | Goeracea oregona | - | 1 | SC |
| Caddisfly, San Marcos saddle-case | Protoptila arca | - | 2 | SC |
| Caddisfly, Schuh's homoplectran | Homoplectra schuhi | - | 1 | SC |
| Caddisfly, Sequatchie | Glyphopsyche sequatchie | - | 4 | C |
| Caddisfly, Siskiyou | Neothremma siskiyou | - | 1 | SC |
| Caddisfly, Siskiyou | Tinodes siskiyou | - | 1 | SC |
| Caddisfly, spiny rhyacophilan | Rhyacophila spinata | - | 1 | SC |
| Caddisfly, Stannard's agarodes | Agarodes stannardi | - | 4 | SC |
| Caddisfly, Texas austrotinodes | Austrotinodes sp. | - | 2 | SC |
| Caddisfly, three-tooth long-horned | Triaenodes tridonta | - | 4 | SC |
| Caddisfly, Tombstone Prairie farulan | Farula reaperi | - | 1 | SC |
| Caddisfly, Tombstone Prairie oligophlebodes | Oligophlebodes mostbento | - | 1 | SC |
| Caddisfly, Vannote's net-spinning | Cheumatopsyche vannotei | - | 5 | SC |
| Caddisfly, Vertrees's ceraclean | Ceraclea vertreesi | - | 1 | SC |
| Caddisfly, zigzag blackwater | Agarodes ziczac | - | 4 | SC |
| Caddisfly, [unnamed] | Agapetus jocassee | - | 4 | SC |
| Caddisfly, [unnamed] | Agarodes alabamensis | - | 4 | SC |
| Caddisfly, [unnamed] | Ceraclea enodis | - | 4 | RT |
| Caddisfly, [unnamed] | Chimarra holzenthali | - | 4 | SC |
| Caddisfly, [unnamed] | Diplectrona rossi | - | 4 | SC |
| Caddisfly, [unnamed] | Helicopsyche paralimnella | - | 4 | SC |
| Caddisfly, [unnamed] | Hydroptila chelops | - | 4 | SC |
| Caddisfly, [unnamed] | Hydroptila englishi | - | 4 | SC |
| Caddisfly, [unnamed] | Hydroptila lagoi | - | 4 | SC |
| Caddisfly, [unnamed] | Hydroptila ouachita | - | 4 | SC |
| Caddisfly, [unnamed] | Lepidostoma etnieri | - | 4 | SC |
| Caddisfly, [unnamed] | Ochotrichia elongiralla | - | 4 | SC |
| Caddisfly, [unnamed] | Polycentropus harrisi | - | 4 | SC |
| Caddisfly, [unnamed] | Psilotreta hansoni | - | 5 | RT |
| Caddisfly, [unnamed] | Setodes epicampes | - | 4 | RT |
| Caddisfly, [unnamed] | Stactiobiella cahaba | - | 4 | SC |
| Caddisfly, [unnamed] | Theliopsyche tallapoosa | - | 4 | SC |
| Caddisfly, [unnamed] | Wormaldia oconee | - | 4 | SC |
| Cahow | Pterodroma cahow | - | Foreign | E |
| Caiman, Apaporis River | Caiman crocodilus apaporiensis | - | Foreign | E |
| Caiman, black | Melanosuchus niger | - | Foreign | E |
| Caiman, broad-snouted | Caiman latirostris | - | Foreign | E |
| Caiman, brown | Caiman crocodilus fuscus (includes Caiman crocodilus chiapasius) | - | Foreign | SAT |
| Caiman, common | Caiman crocodilus crocodilus | - | Foreign | SAT |
| Caiman, Yacare | Caiman yacare | - | Foreign | T |
| California-lilac, maritime | Ceanothus maritimus | - | 1 | SC |
| Caltrop, perennial | Kallstroemia perennans | - | 2 | SC |
| Camasey, Petites Graines | Graffenrieda ottoschulzii | - | 4 | SC |
| Camassia, Leichtlin | Camassia leichtlinii leichtlinii | - | 1 | RT |
| Camel cricket, Tanner's black | Utabaenetes tanneri | - | 6 | SC |
| Camel, Bactrian | Camelus bactrianus | - | Foreign | E |
| Campanula, Castle Crags | Campanula shetleri | - | 1 | RT |
| Campeloma, slender | Campeloma decampi | - | 4 | E |
| Campion, fringed | Silene polypetala | - | 4 | E |
| Campion, Mission Dolores | Silene verecunda verecunda | - | 1 | UR |
| Campylopus, savannah | Campylopus carolinae | - | 4 | SC |
| Capa rosa | Callicarpa ampla | - | 4 | E |
| Capercaillie, Cantabrian | Tetrao urogallus cantabricus | - | Foreign | PE |
| Capshell, Rocky Mountain | Acroloxus coloradensis | - | 6 | RT |
| Caracara, Audubon's crested | Polyborus plancus audubonii | U.S.A. (FL) | 4 | T |
| Carelia, spp. (ca 12) | Carelia spp. (ca 12) | - | 1 | SC |
| Caribou, Dolphin-Union | Rangifer tarandus ssp. groenlandicus | - | Foreign | SU |
| Caribou, Peary | Rangifer tarandus pearyi | - | Foreign | SU |
| Caribou, woodland | Rangifer tarandus caribou | MT pop. | 6 | UR |
| Caribou, woodland | Rangifer tarandus caribou | U.S.A. (ID, WA), Canada (that part of S.E. British Columbia bounded by the U.S.-Can. border, Columbia R., Kootenay R., Kootenay L., and Kootenai R.) | 1 | E |
| Carpenteria, [unnamed] | Carpenteria californica | - | 1 | RT |
| Carposinid moth, green | Carposina viridis | - | 1 | SC |
| Casebearer moth, chestnut | Coleophora leucochrysella | - | 5 | SC |
| Cat's-eye, Terlingua Creek | Cryptantha crassipes | - | 2 | E |
| Cat, Andean | Felis jacobita | - | Foreign | E |
| Cat, Asian golden (=Temmnick's) | Catopuma (=Felis) temminckii | - | Foreign | E |
| Cat, black-footed | Felis nigripes | - | Foreign | E |
| Cat, flat-headed | Prionailurus (=Felis) planiceps | - | Foreign | E |
| Cat, Iriomote | Prionailurus (=Felis) bengalensis iriomotensis | - | Foreign | E |
| Cat, leopard | Prionailurus (=Felis) bengalensis bengalensis | - | Foreign | E |
| Cat, marbled | Pardofelis (=Felis) marmorata | - | Foreign | E |
| Cat, Pakistan sand | Felis margarita scheffeli | - | Foreign | E |
| Cat, tiger | Leopardus (=Felis) tigrinus | - | Foreign | E |
| Catchfly, Blue Ridge | Silene ovata | - | 4 | SC |
| Catchfly, Butte County | Silene occidentalis longistipitata | - | 1 | SC |
| Catchfly, cascade head | Silene douglasii oraria | - | 1 | SC |
| Catchfly, Grand Canyon | Silene rectiramea | - | 2 | SC |
| Catchfly, Jan's | Silene nachlingerae | - | 1 | SC |
| Catchfly, Marble Mountain | Silene marmorensis | - | 1 | SC |
| Catchfly, Plank's | Silene plankii | - | 2 | RT |
| Catchfly, plateau | Silene petersonii | - | 6 | SC |
| Catchfly, Red Canyon | Silene petersonii minor | - | 6 | RT |
| Catchfly, red fir | Silene invisa | - | 1 | RT |
| Catchfly, Red Mountain | Silene campanulata campanulata | - | 1 | RT |
| Catchfly, royal | Silene regia | - | 3 | RT |
| Catchfly, scarlet | Silene subciliata | - | 2 | SC |
| Catchfly, Spalding's | Silene spaldingii | - | 1 | T |
| Catchfly, [unnamed] | Silene virginica robusta | - | 5 | SC |
| Catfish | Pangasius sanitwongsei | - | Foreign | E |
| Catfish, Chihuahua | Ictalurus sp. | - | 2 | SC |
| Catfish, headwater | Ictalurus lupus | - | 2 | RT |
| Catfish, Thailand giant | Pangasianodon gigas | - | Foreign | E |
| Catfish, Yaqui | Ictalurus pricei | - | 2 | T |
| Catfoot, saxicola rock | Gnaphalium obtusifolium saxicola | - | 3 | SC |
| Catseye, Atwood's | Cryptantha atwoodii | - | 2 | RT |
| Catseye, Barneby | Cryptantha barnebyi | - | 6 | RT |
| Catseye, bristlecone | Cryptantha roosiorum | - | 1 | SC |
| Catseye, cliffdweller's candlestick | Cryptantha elata | - | 6 | RT |
| Catseye, compact | Cryptantha compacta | - | 6 | SC |
| Catseye, Graham | Cryptantha grahamii | - | 6 | RT |
| Catseye, Grand Junction | Cryptantha aperta | - | 6 | SC |
| Catseye, Johnston | Cryptantha johnstonii | - | 6 | RT |
| Catseye, Jones | Cryptantha jonesiana | - | 6 | RT |
| Catseye, Weber's | Cryptantha weberi | - | 6 | RT |
| Catseye, yellow-white | Cryptantha ochroleuca | - | 6 | SC |
| Catseye, [unnamed] | Cryptantha breviflora | - | 1 | RT |
| Catseye, [unnamed] | Cryptantha insolita | - | 1 | SC |
| Catseye, [unnamed] | Cryptantha semiglabra | - | 2 | UR |
| Catseye, [unnamed] | Cryptantha shackletteana | - | 7 | SC |
| Catseye, [unnamed] | Cryptantha sobolifera | - | 6 | RT |
| Catseye, [unnamed] | Cryptantha stricta | - | 6 | RT |
| Catspaw (=purple cat's paw pearlymussel) | Epioblasma obliquata obliquata | U.S.A. (AL;The free-flowing reach of the Tennessee R. from the base of Wilson Dam downstream to the backwaters of Pickwick Reservoir [about 12 RM (19 km)] and the lower 5 RM [8 km] of all tributaries to this reach in Colbert and Lauderdale Cos., see 17.85(a)) | 3 | EXPN |
| Catspaw (=purple cat's paw pearlymussel) | Epioblasma obliquata obliquata | Entire Range; Except where listed as Experimental Populations | 3 | E |
| Catspaw, narrow | Epioblasma lenior | - | 4 | RT |
| Catspaw, white (pearlymussel) | Epioblasma obliquata perobliqua | - | 3 | E |
| Caulostramina, Jaeger's | Caulostramina jaegeri | - | 1 | SC |
| Cave beetle, Baker Station | Pseudanophthalmus insularis | - | 4 | C |
| Cave beetle, beaver | Pseudanophthalmus major | entire | 4 | RT |
| Cave beetle, Benderman's | Pseudanophthalmus bendermani | - | 4 | SC |
| Cave beetle, Blowing | Pseudanophthalmus ventus | - | 4 | SC |
| Cave beetle, Cane Creek | Pseudanophthalmus occidentalis | - | 4 | SC |
| Cave beetle, Catherine's | Pseudanophthalmus catherinae | - | 4 | SC |
| Cave beetle, Clifton | Pseudanophthalmus caecus | - | 4 | C |
| Cave beetle, Clifton | Pseudanoptha caecus | - | NA | SU |
| Cave beetle, coleman | Pseudanophthalmus colemanensis | - | 4 | C |
| Cave beetle, crossroads | Pseudanophthalmus intersectus | - | 5 | SC |
| Cave beetle, Cudjo's | Pseudanophthalmus hirsutus | - | 5 | SC |
| Cave beetle, deceptive | Pseudanophthalmus deceptivus | - | 5 | SC |
| Cave beetle, Dry Fork Valley | Pseudanophthalmus montanus | - | 5 | SC |
| Cave beetle, Endless Caverns | Pseudanophthalmus avernus | - | 5 | SC |
| Cave beetle, Engelhardt's | Pseudanophthalmus engelhardti | - | 4 | SC |
| Cave beetle, Flyn's hick | Pseudanophthalmus simplex | - | 4 | SC |
| Cave beetle, Fowler's | Pseudanophthalmus fowlerae | - | 4 | C |
| Cave beetle, garden | Pseudanophthalmus hortulanus | - | 5 | SC |
| Cave beetle, Georgian | Pseudanophthalmus georgiae | - | 4 | SC |
| Cave beetle, Grassy Cove | Pseudanophthalmus jonesi | - | 4 | SC |
| Cave beetle, greater Adams | Pseudanophthalmus pholeter | - | 4 | RT |
| Cave beetle, Greenbrier Valley | Pseudanophthalmus fuscus fuscus | - | 5 | SC |
| Cave Beetle, Holsinger's | Pseudanophthalmus holsingeri | - | 5 | UR |
| Cave beetle, Hubbard's | Pseudanophthalmus hubbardi | - | 5 | SC |
| Cave beetle, Hubricht's | Pseudanophthalmus hubrichti | - | 5 | SC |
| Cave beetle, icebox | Pseudanophthalmus frigidus | - | 4 | C |
| Cave beetle, Illinois | Pseudanophthalmus illinoisensis | - | 3 | SC |
| Cave beetle, Indian Grave Point (=Soothsayer) | Pseudanophthalmus tiresias | - | 4 | C |
| Cave beetle, inquirer | Pseudanophthalmus inquisitor | - | 4 | C |
| Cave beetle, Kramer's | Pseudanophthalmus krameri | - | 3 | SC |
| Cave beetle, Lallemant's | Pseudanophthalmus lallemanti | - | 5 | SC |
| Cave beetle, lesser Adams | Pseudanophthalmus cataryctos | - | 4 | RT |
| Cave beetle, limestone | Pseudanophthalmus calcareus | - | 4 | SC |
| Cave beetle, Little Kennedy | Pseudanophthalmus cordicollis | - | 5 | SC |
| Cave beetle, long-headed | Pseudanophthalmus longiceps | - | 4 | SC |
| Cave beetle, Louisville | Pseudanophthalmus troglodytes | - | 4 | C |
| Cave beetle, Maiden Spring | Pseudanophthalmus virginicus | - | 5 | SC |
| Cave beetle, Martin | Pseudanophthalmus pusillus | - | 4 | SC |
| Cave beetle, Maryland | Pseudanopthalmus sp. | - | 5 | SC |
| Cave beetle, Meridith | Pseudanophthalmus sidus | - | 4 | SC |
| Cave beetle, Mystic | Pseudanophthalmus hadenoecus | - | 5 | SC |
| Cave beetle, Narrows | Pseudanophthalmus egberti | - | 5 | SC |
| Cave beetle, Natural Bridge | Pseudanophthalmus pontis | - | 5 | SC |
| Cave beetle, Nelson's | Pseudanophthalmus nelsoni | - | 5 | SC |
| Cave beetle, New Mammoth Cave | Pseudanophthalmus scutilis | - | 4 | SC |
| Cave beetle, Nobletts | Pseudanophthalmus paulus | - | 4 | C |
| Cave beetle, Norton's | Pseudanophthalmus nortoni | - | 4 | SC |
| Cave beetle, Ohio | Pseudanophthalmus ohioensis | - | 3 | SC |
| Cave beetle, overlooked | Pseudanophthalmus praetermissus | - | 5 | SC |
| Cave beetle, pale | Pseudanophthalmus pallidus | - | 4 | SC |
| Cave beetle, Payne's | Pseudanophthalmus paynei | - | 4 | SC |
| Cave beetle, Petrunkevitch's | Pseudanophthalmus petrunkevitchi | - | 5 | SC |
| Cave beetle, Rich Mountain | Pseudanophthalmus krekeleri | - | 5 | SC |
| Cave beetle, Rogers' | Pseudanophthalmus rogersae | - | 4 | SC |
| Cave beetle, Saint Paul | Pseudanophthalmus sanctipauli | - | 5 | SC |
| Cave beetle, Sawmill Hollow | Pseudanophthalmus scholasticus | - | 4 | SC |
| Cave beetle, Seneca | Pseudanophthalmus potomaca senecae | - | 5 | SC |
| Cave beetle, Sensabush | Pseudanophthalmus paradoxus | - | 4 | SC |
| Cave beetle, Sequoyah Caverns | Pseudanophthalmus sequoyah | - | 4 | SC |
| Cave beetle, Shenandoah | Pseudanophthalmus limicola | - | 5 | SC |
| Cave beetle, Silken | Pseudanophthalmus sericus | - | 5 | SC |
| Cave beetle, South Branch Valley | Pseudanophthalmus potomaca potomaca | - | 5 | SC |
| Cave beetle, spotted | Pseudanophthalmus punctatus | - | 5 | SC |
| Cave beetle, stone-dwelling | Pseudanophthalmus hypolithos | - | 4 | SC |
| Cave beetle, Straley's | Pseudanophthalmus quadratus | - | 5 | SC |
| Cave beetle, surprising | Pseudanophthalmus inexpectatus | - | 4 | RT |
| Cave beetle, tapered | Pseudanophthalmus fastigatus | - | 4 | SC |
| Cave beetle, Tatum | Pseudanophthalmus parvus | - | 4 | C |
| Cave beetle, thin-neck | Pseudanophthalmus parvicollis | - | 5 | SC |
| Cave beetle, Thomas' | Pseudanophthalmus thomasi | - | 5 | SC |
| Cave beetle, Union County | Pseudanophthalmus unionis | - | 4 | SC |
| Cave beetle, Wallace's | Pseudanophthalmus wallacei | - | 4 | SC |
| Cave beetle, [unnamed] | Pseudanophthalmus audax | - | 4 | SC |
| Cave beetle, [unnamed] | Pseudanophthalmus conditus | - | 4 | SC |
| Cave beetle, [unnamed] | Pseudanophthalmus exoticus | - | 4 | SC |
| Cave beetle, [unnamed] | Pseudanophthalmus globiceps | - | 4 | SC |
| Cave beetle, [unnamed] | Pseudanophthalmus horni | - | 4 | SC |
| Cave beetle, [unnamed] | Pseudanophthalmus puteanus | - | 4 | SC |
| Cave beetle, [unnamed] | Pseudanophthalmus simulans | - | 4 | SC |
| Cave beetle, [unnamed] | Pseudanophthalmus tenebrosus | - | 4 | SC |
| Cave beetle, [unnamed] | Pseudanopthalmus gracilis | - | 5 | SC |
| Cave beetle, [unnamed] | Pseudanopthalmus sylvaticus | - | 5 | SC |
| Cave beetle, [unnamed] | Pseudanopthalmus vicarius | - | 5 | SC |
| Cavefish, Alabama | Speoplatyrhinus poulsoni | - | 4 | E |
| Cavefish, northern | Amblyopsis spelaea | - | 3 | SC |
| Cavefish, Ozark | Amblyopsis rosae | - | 4 | T |
| cavefish, Southern | typhlichthys subterraneus | - | 2 | SC |
| Cavesnail, Greenbrier | Fontigens turritella | - | 5 | SC |
| Cavesnail, mimic | Phreatodrobia imitata | - | 2 | SC |
| Cavesnail, tapered | Fontigens holsingeri | - | 5 | SC |
| Cavesnail, Tumbling Creek | Antrobia culveri | - | 3 | E |
| Ceanothus, Bolinas | Ceanothus masonii | - | 1 | SC |
| Ceanothus, Calistoga | Ceanothus divergens | - | 1 | SC |
| Ceanothus, coyote | Ceanothus ferrisae | - | 8 | E |
| Ceanothus, Hearst's | Ceanothus hearstiorum | - | 1 | SC |
| Ceanothus, Lakeside | Ceanothus cyaneus | - | 1 | SC |
| Ceanothus, Monterey | Ceanothus cuneatus rigidus | - | 1 | SC |
| Ceanothus, Mt. Vision | Ceanothus gloriosus porrectus | - | 1 | SC |
| Ceanothus, Nipomo | Ceanothus impressus nipomensis | - | 1 | RT |
| Ceanothus, Pine Hill | Ceanothus roderickii | - | 8 | E |
| Ceanothus, Rincon | Ceanothus confusus | - | 1 | SC |
| Ceanothus, Sonoma | Ceanothus sonomensis | - | 1 | SC |
| Ceanothus, Vail Lake | Ceanothus ophiochilus | - | 8 | T |
| Ceanothus, Vine Hill | Ceanothus foliosus vineatus | - | 1 | SC |
| Ceanothus, wart-stemmed | Ceanothus verrucosus | - | 1 | SC |
| Ceanothus, [unnamed] | Ceanothus arboreus | - | 1 | RT |
| Centaury, spring-loving | Centaurium namophilum | - | 8 | T |
| Chachalaca, Utila | Ortalis vetula | - | Foreign | UR |
| Chaenactis, Parish's | Chaenactis parishii | - | 1 | RT |
| Chaff-flower, round-leaved | Achyranthes splendens var. rotundata | - | 1 | E |
| Chaffseed, American | Schwalbea americana | - | 5 | E |
| Chamois, Apennine | Rupicapra rupicapra ornata | - | Foreign | E |
| chaparral, Shasta | Trilobopsis roperi | - | 8 | SU |
| chaparral, Tehama | Trilobopsis tehamana | - | 8 | SU |
| chaparral, Tehama | Trilobopsis tehamana | - | 8 | SU |
| chat, Yellow-breasted | icteria virens | - | 6 | SC |
| Checker-mallow, Keck's | Sidalcea keckii | - | 8 | E |
| Checker-mallow, Kenwood Marsh | Sidalcea oregana ssp. valida | - | 8 | E |
| Checker-mallow, Nelson's | Sidalcea nelsoniana | - | 1 | T |
| Checker-mallow, pedate | Sidalcea pedata | - | 8 | E |
| Checkerbloom, Dwarf | Sidalcea malviflora ssp. virgata | - | 1 | SC |
| Checkerbloom, Parish's | Sidalcea hickmanii parishii | - | 8 | RT |
| Checkerbloom, Scadden Flat | Sidalcea stipularis | - | 1 | SC |
| Checkermallow, Del Norte | Sidalcea malviflora elegans | - | 1 | RT |
| Checkermallow, Henderson's | Sidalcea hendersonii | - | 1 | RT |
| Checkermallow, Marin | Sidalcea hickmanii viridis | - | 1 | SC |
| Checkermallow, meadow | Sidalcea campestris | - | 1 | RT |
| Checkermallow, Owens Valley | Sidalcea covillei | - | 1 | SC |
| Checkermallow, water-loving | Sidalcea oregana hydrophila | - | 1 | RT |
| Checkermallow, Wenatchee Mountains | Sidalcea oregana var. calva | - | 1 | E |
| Checkermallow, [unnamed] | Sidalcea malvaeflora patula | - | 1 | SC |
| Checkerspot, mono | Euphydryas editha monoensis | - | 1 | SC |
| Checkerspot, Morand's | Euphydryas anicia morandi | - | 1 | SC |
| Checkerspot, Taylor's (=whulge) | Euphydryas editha taylori | - | 1 | C |
| Cheesebush Sanderson's | Hymenoclea sandersonii | - | 6 | SC |
| Cheetah | Acinonyx jubatus | - | Foreign | E |
| Chia, San Jacinto Mountains | Salvia columbariae ziegleri | - | 1 | RT |
| Chickweed | Stellaria irrigua | - | 6 | RT |
| Chickweed, Aleutian | Cerastium aleuticum | - | 7 | RT |
| Chickweed, field, long-hairy | Cerastium arvense villosissimum | - | 5 | SC |
| Chickweed, mouse-ear | Cerastium clawsonii | - | 2 | RT |
| Chimpanzee | Pan troglodytes | Wherever found in captivity | Foreign | T |
| Chimpanzee | Pan troglodytes | Wherever found in the wild | Foreign | E |
| Chimpanzee, pygmy | Pan paniscus | - | Foreign | E |
| Chinchilla | Chinchilla brevicaudata boliviana | - | Foreign | E |
| Chinquapin, Ozark | Castanea pumila ozarkensis | - | 4 | UR |
| Chipmunk, gray-footed | Tamias canipes | - | 2 | SC |
| Chipmunk, Hidden Forest Uinta | Eutamias umbrinus nevadensis | - | 1 | SC |
| Chipmunk, lodgepole | Tamias speciosus speciosus | - | 1 | SC |
| Chipmunk, Mount Ellen Uinta | Tamias umbrinus sedulus | - | 6 | SC |
| Chipmunk, Organ Mountains Colorado | Eutamias quadrivittatus australis | - | 2 | SC |
| Chipmunk, Palmer's | Eutamias palmeri | - | 1 | SC |
| Chipmunk, Penasco least | Eutamias minimus atristriatus | - | 2 | RT |
| Cholla, Blue Diamond | Opuntia whipplei multigeniculata | - | 1 | RT |
| Cholla, Munz | Opuntia munzii | - | 1 | SC |
| Cholla, sand | Opuntia pulchella | - | 1 | RT |
| Cholla, Santa Fe | Opuntia viridiflora | - | 2 | SC |
| Cholla, silver | Opuntia imbricata argentea | - | 2 | SC |
| Cholla, snake | Opuntia parryi serpentina | - | 1 | SC |
| Cholla, Wiggins' | Opuntia wigginsii | - | 1 | RT |
| Christmas tree, desert | Pholisma arenarium | - | 1 | RT |
| Chub, Alvord | Gila alvordensis | - | 1 | SC |
| Chub, Arkansas River speckled | Macrhybopsis aestivalis tetranemus | - | 2 | SC |
| Chub, arroyo | Gila orcutti | - | 1 | SC |
| Chub, Big Smoky Valley tui | Gila bicolor ssp. | Big Smoky | 1 | SC |
| Chub, bonytail | Gila elegans | entire | 6 | E |
| Chub, Borax Lake | Gila boraxobius | - | 1 | E |
| Chub, Catlow tui | Gila bicolor ssp. | Catlow | 1 | SC |
| Chub, Chihuahua | Gila nigrescens | - | 2 | T |
| Chub, Cow Head tui | Gila bicolor vaccaceps | entire | 8 | RT |
| Chub, Dixie Valley tui | Gila bicolor ssp. | Dixie Valley | 1 | SC |
| Chub, Fish Creek Springs tui | Gila bicolor euchila | - | 1 | SC |
| Chub, Fish Lake Valley tui | Gila bicolor ssp. | Fish Lake | 1 | SC |
| Chub, flame | Hemitremia flammea | - | 4 | SC |
| Chub, flathead | Platygobio gracilis | - | 3 | SC |
| Chub, Gila | Gila intermedia | - | 2 | E |
| Chub, headwater | Gila nigra | - | 2 | C |
| Chub, High Rock Springs tui | Gila bicolor ssp. | High Rock | 1 | RT |
| Chub, Hot Creek Valley tui | Gila bicolor ssp. | - | 1 | SC |
| Chub, humpback | Gila cypha | entire | 6 | E |
| Chub, Hutton tui | Gila bicolor ssp. | Hutton | 1 | T |
| Chub, Independence Valley tui | Gila bicolor isolata | - | 1 | SC |
| Chub, least | Iotichthys phlegethontis | - | 6 | C |
| Chub, leatherside | Gila copei | - | 6 | SC |
| Chub, Leatherside | Snyderichthys copei | - | 6 | UR |
| Chub, lined | Hybopsis lineapunctata | - | 4 | RT |
| Chub, Mohave tui | Gila bicolor mohavensis | - | 8 | E |
| Chub, Newark Valley tui | Gila bicolor newarkensis | - | 1 | SC |
| Chub, Oregon | Oregonichthys crameri | - | 1 | T |
| Chub, Owens tui | Gila bicolor snyderi | - | 8 | E |
| Chub, Pahranagat roundtail | Gila robusta jordani | - | 8 | E |
| Chub, Pleasant Valley tui | Gila bicolor ssp. | Pleasant Valley | 1 | SC |
| Chub, Railroad Valley tui | Gila bicolor ssp. | Railroad Valley | 1 | UR |
| Chub, roundtail | Gila robusta | Lower Colorado River Basin DPS | 2 | C |
| Chub, Sandhills | Semotilus lumbee | - | 4 | RT |
| Chub, Sheldon tui | Gila bicolor eurysoma | - | 1 | SC |
| Chub, sicklefin | Macrhybopsis meeki | - | 6 | RT |
| Chub, slender | Erimystax cahni | - | 4 | T |
| Chub, slender | Erimystax cahni | U.S.A. (TN - specified portions of the French Broad and Holston Rivers; see 17.84(s)(1)(i)) | 4 | EXPN |
| Chub, Sonora | Gila ditaenia | - | 2 | T |
| Chub, spotfin | Erimonax monachus | U.S.A. (TN - specified portions of the French Broad and Holston Rivers; see 17.84(m)(1)(iii)) | 4 | EXPN |
| Chub, spotfin | Erimonax monachus | Entire | 4 | T |
| Chub, spotfin | Erimonax monachus | Shoal Creek | 4 | EXPN |
| Chub, spotfin | Erimonax monachus | Tellico River, between the backwaters of the Tellico Reservoir and the Tellico Ranger Station, in Monroe County, Tennessee | 4 | EXPN |
| Chub, sturgeon | Macrhybopsis gelida | - | 6 | RT |
| Chub, Summer Basin tui | Gila bicolor ssp. | Summer Basin | 1 | SC |
| Chub, Thicktail | Gila crassicauda | - | 1 | RT |
| Chub, Umpqua Oregon | Oregonichthys kalawatseti | - | 1 | SC |
| Chub, Virgin River | Gila seminuda (=robusta) | - | 6 | E |
| Chub, XL Spring tui | Gila bicolor oregonensis | - | 1 | SC |
| Chub, Yaqui | Gila purpurea | - | 2 | E |
| Chuckwalla | Sauromalus obesus | - | 1 | SC |
| Chuckwalla, San Esteban Island | Sauromalus varius | - | Foreign | E |
| Chumbo, Higo | Harrisia portoricensis | - | 4 | T |
| Chupacallos | Pleodendron macranthum | - | 4 | E |
| Cicek (minnow) | Acanthorutilus handlirschi | - | Foreign | E |
| Cinclodes, royal | Cinclodes aricomae | - | Foreign | PE |
| Cinquefoil Macoun's | Potentilla macounii | - | 6 | SC |
| Cinquefoil, Ballona | Potentilla multijuga | - | 1 | SC |
| cinquefoil, cliff | Potentilla rimicola | - | 1 | SC |
| Cinquefoil, Front Range | Potentilla effusa rupincola | - | 6 | SC |
| Cinquefoil, Kingston Mountains | Ivesia patellifera | - | 1 | SC |
| Cinquefoil, Robbins' | Potentilla robbinsiana | - | 5 | DM |
| Cinquefoil, Soldier Meadows | Potentilla basaltica | - | 8 | C |
| Cinquuefoil, Ramona | Horkelia truncata | - | 1 | RT |
| Cirsium, sp. nov. ined. | Cirsium sp. | R6 | 6 | SC |
| Cisco Bonneville | Prosopium gemmifer | - | 6 | SC |
| Cisco, blackfin | Coregonus nigripinnis nigripinnis | - | 3 | RT |
| Cisco, deepwater | Coregonus johannae | - | 3 | RT |
| Cisco, longjaw | Coregonus alpenae | - | 3 | D3A |
| Cisco, shortjaw | Coregonus zenithicus | - | 3 | SC |
| Cisco, shortnose | Coregonus reighardi | - | 3 | SC |
| Civet, Malabar large-spotted | Viverra civettina (=megaspila c.) | - | Foreign | E |
| Cladonia, Florida perforate | Cladonia perforata | - | 4 | E |
| Clam shrimp, American | Limnadia lenticularis | - | 5 | SC |
| Clam shrimp, Connecticut | Eulimnadia stoningtonensis | - | 5 | SC |
| Clam shrimp, Faxon's | Eulimnadia agassizii | - | 5 | SC |
| Clarkia, arid northern | Clarkia borealis arida | - | 1 | SC |
| Clarkia, beaked | Clarkia rostrata | - | 1 | SC |
| Clarkia, Caliente | Clarkia temblorensis calientensis | - | 1 | SC |
| Clarkia, East Bay | Clarkia concinna automixa | - | 1 | SC |
| Clarkia, Enterprise | Clarkia mosquinii xerophila | - | 1 | SC |
| Clarkia, Mariposa | Clarkia biloba australis | - | 1 | RT |
| Clarkia, Merced | Clarkia lingulata | - | 1 | RT |
| Clarkia, Mosquin's | Clarkia mosquinii mosquinii | - | 1 | SC |
| Clarkia, Pismo | Clarkia speciosa ssp. immaculata | - | 8 | E |
| Clarkia, Presidio | Clarkia franciscana | - | 8 | E |
| Clarkia, Small's southern | Clarkia australis | - | 1 | RT |
| Clarkia, Springville | Clarkia springvillensis | - | 8 | T |
| Clarkia, Tomales | Clarkia concinna raichei | - | 1 | SC |
| Clarkia, Vine Hill | Clarkia imbricata | - | 8 | E |
| Clarkia, [unnamed] | Clarkia amoena pacifica | - | 1 | RT |
| Clarkia, [unnamed] | Clarkia amoena whitneyi | - | 1 | RT |
| clay-cress, Hammitt's | sibaropsis hammittii | - | 6 | SC |
| Claytonia, fell fields | Claytonia megarhiza bellidiflora | - | 1 | RT |
| Click beetle, ambiguous eopenthes | Eopenthes ambiguus | - | 1 | SC |
| Click beetle, arduous eopenthes | Eopenthes arduus | - | 1 | SC |
| Click beetle, cognatus eopenthes | Eopenthes cognatus | - | 1 | SC |
| Click beetle, common eopenthes | Eopenthes plebeius | - | 1 | SC |
| Click beetle, death eopenthes | Eopenthes funebris | - | 1 | SC |
| Click beetle, deceptive eopenthes | Eopenthes deceptor | - | 1 | SC |
| Click beetle, germanus eopenthes | Eopenthes germanus | - | 1 | SC |
| Click beetle, golden eopenthes | Eopenthes auratus | - | 1 | SC |
| Click beetle, Hatch's | Eanus hatchi | - | 1 | SC |
| Click beetle, hidden eopenthes | Eopenthes celatus | - | 1 | SC |
| Click beetle, Kauai eopenthes | Eopenthes kauaiensis | - | 1 | SC |
| Click beetle, muticus eopenthes | Eopenthes muticus | - | 1 | SC |
| Click beetle, Necker itodacnus | Itodacnus novicornis | - | 1 | SC |
| Click beetle, pallipes eopenthes | Eopenthes pallipes | - | 1 | SC |
| Click beetle, politus eopenthes | Eopenthes politus | - | 1 | SC |
| Click beetle, strange itodacnus | Itodacnus paradoxus | - | 1 | SC |
| Click beetle, tarsalis eopenthes | Eopenthes tarsalis | - | 1 | SC |
| Click beetle, tinged eopenthes | Eopenthes tinctus | - | 1 | SC |
| Click beetle, unicolored eopenthes | Eopenthes unicolor | - | 1 | SC |
| Click beetle, weak eopenthes | Eopenthes debilis | - | 1 | SC |
| Cliff-rose, Arizona | Purshia (=Cowania) subintegra | - | 2 | E |
| Clover, Beatley's | Trifolium andersonii beatleyae | - | 1 | RT |
| Clover, DeDecker's | Trifolium dedeckerae | - | 1 | RT |
| Clover, frisco | Trifolium friscanum | - | 6 | UR |
| Clover, Kate's-mountain | Trifolium virginicum | - | 5 | RT |
| Clover, Lemmon's | Trifolium lemmonii | - | 1 | RT |
| Clover, Monterey | Trifolium trichocalyx | - | 8 | E |
| Clover, Owyhee | Trifolium owyheense | - | 1 | SC |
| Clover, Pacific Grove | Trifolium polyodon | - | 1 | RT |
| Clover, parasol | Trifolium bolanderi | - | 1 | SC |
| Clover, running buffalo | Trifolium stoloniferum | - | 3 | E |
| Clover, showy Indian | Trifolium amoenum | - | 8 | E |
| Clover, Thompson's | Trifolium thompsonii | - | 1 | SC |
| Clover, [unnamed] | Trifolium barnebyi | - | 6 | SC |
| Clover, [unnamed] | Trifolium calcaricum | - | 5 | SC |
| Clover, [unnamed] | Trifolium leibergii | - | 1 | SC |
| Clover, [unnamed] | Trifolium macilentum rollinsii | - | 1 | SC |
| Clover, [unnamed] | Trifolium neurophyllum | - | 2 | SC |
| Clover, [unnamed] | Trifolium plumosum amplifolium | - | 1 | RT |
| Clover, [unnamed] | Trifolium plumosum plumosum | - | 1 | RT |
| Clubmoss, [unnamed] | Lycopodium portoricense | - | 4 | RT |
| Clubshell | Pleurobema clava | U.S.A. (AL;The free-flowing reach of the Tennessee R. from the base of Wilson Dam downstream to the backwaters of Pickwick Reservoir [about 12 RM (19 km)] and the lower 5 RM [8 km] of all tributaries to this reach in Colbert and Lauderdale Cos., see 17.85(a)) | 4 | EXPN |
| Clubshell | Pleurobema clava | Entire Range; Except where listed as Experimental Populations | 5 | E |
| Clubshell, Alabama | Pleurobema troschelianum | - | 4 | UR |
| Clubshell, black | Pleurobema curtum | - | 4 | E |
| Clubshell, ovate | Pleurobema perovatum | - | 4 | E |
| Clubshell, painted | Pleurobema chattanoogaense | - | 4 | UR |
| Clubshell, southern | Pleurobema decisum | - | 4 | E |
| Clubshell, Tennessee | Pleurobema oviforme | - | 4 | SC |
| Clubtail, bronze | Stylurus townesi | - | 4 | SC |
| Clubtail, Cherokee | Gomphus consanguis | - | 4 | SC |
| Clubtail, elusive | Gomphus notatus | - | 3 | SC |
| Clubtail, Lynn's | Gomphus lynnae | - | 1 | SC |
| Clubtail, sandhills | Gomphus parvidens carolinus | - | 4 | SC |
| Clubtail, Septima's | Gomphus septima | - | 4 | SC |
| Clubtail, Tennessee | Gomphus sandrius | - | 4 | SC |
| Clubtail, variegated | Progomphus bellei | - | 4 | SC |
| Clubtail, Westfall's | Gomphus westfalli | - | 4 | SC |
| coachwhip, Red | masticophis flagellum ssp. piceus | - | 6 | SC |
| Cobana negra | Stahlia monosperma | - | 4 | T |
| Cochito | Phocoena sinus | - | Foreign | E |
| Cockatoo, Philippine | Cacatua haematuropygia | - | Foreign | UR |
| Cockatoo, salmon-crested | Cacatua moluccensis | - | Foreign | PT |
| Cockatoo, white | Cacatua alba | - | Foreign | UR |
| Cockatoo, yellow-crested | Cacatua sulphurea | - | Foreign | UR |
| Coenonycha, San Clemente Island | Coenonycha clementina | - | 1 | SC |
| Coil, shaggy | Helicodiscus diadema | - | 5 | SC |
| Coil, toothy | Helicodiscus hexodon | - | 4 | SC |
| collinsia, San Francisco | collinsia multicolor | - | 8 | SC |
| Collomia, bristle-flowered | Collomia macrocalyx | - | 1 | RT |
| Collomia, Crater Lake | Collomia mazama | - | 1 | SC |
| Collomia, talus | Collomia debilis larsenii | - | 1 | RT |
| Colubrina, Las Animas | Colubrina californica | - | 2 | RT |
| Columbine Graham's | Aquilegia grahamii | - | 6 | RT |
| Columbine Grahams | Aquilegia grahamii | - | 6 | SC |
| Columbine, Canadian, | Aquilegia canadensis australis | - | 4 | SC |
| Columbine, Hinckley's | Aquilegia chrysantha hinckleyana | - | 2 | SC |
| Columbine, Jones' | Aquilegia jonesii | - | 6 | RT |
| Columbine, Laramie | Aquilegia laramiensis | - | 6 | SC |
| Columbine, long spur | Aquilegia longissima | - | 2 | SC |
| Columbine, Mancos | Aquilegia micrantha mancosana | - | 6 | RT |
| Columbine, [unnamed] | Aquilegia chrysantha chaplinei | - | 2 | RT |
| Columbine, [unnamed] | Aquilegia chrysantha rydbergii | - | 2 | RT |
| Combleaf | Polyctenium williamsiae | - | 1 | SC |
| Combshell, Cumberlandian | Epioblasma brevidens | U.S.A. (AL;The free-flowing reach of the Tennessee R. from the base of Wilson Dam downstream to the backwaters of Pickwick Reservoir [about 12 RM (19 km)] and the lower 5 RM [8 km] of all tributaries to this reach in Colbert and Lauderdale Cos., see 17.85(a)) | 4 | EXPN |
| Combshell, Cumberlandian | Epioblasma brevidens | Entire Range; Except where listed as Experimental Populations | 4 | E |
| Combshell, Cumberlandian | Epioblasma brevidens | U.S.A. (TN - specified portions of the French Broad and Holston Rivers; see 17.85(b)(1)) | 4 | EXPN |
| Combshell, round | Epioblasma personata | - | 4 | RT |
| Combshell, southern | Epioblasma penita | - | 4 | E |
| Combshell, upland | Epioblasma metastriata | - | 4 | E |
| Condor, Andean | Vultur gryphus | - | Foreign | E |
| Condor, California | Gymnogyps californianus | U.S.A. (specific portions of Arizona, Nevada, and Utah) | 1 | EXPN |
| Condor, California | Gymnogyps californianus | U.S.A. only, except where listed as an experimental population below | 8 | E |
| Coneflower, bog | Rudbeckia scabrifolia | - | 2 | SC |
| Coneflower, smooth | Echinacea laevigata | - | 4 | E |
| Coneflower, Tennessee purple | Echinacea tennesseensis | - | 4 | E |
| Coneflower, yellow | Rudbeckia nitida nitida | - | 4 | SC |
| Coontie, Florida | Zamia integrifolia pigmaea | - | 4 | RT |
| Coot, Caribbean | Fulica caribaea | Puerto Rican | 4 | SC |
| Coot, Hawaiian | Fulica americana alai | - | 1 | E |
| Cooter, Suwanee | Pseudemys concinna suwaniensis | - | 4 | RT |
| Copepod | Acanthocyclops columbiensis | - | NA | RT |
| Copper, Clayton's | Lycaena dorcas claytoni | - | 5 | SC |
| Copper, Hermes | Lycaena hermes | - | 8 | UR |
| Copper, White Mountains | Lycaena rubicus ssp. | - | 1 | SC |
| Coqui, golden | Eleutherodactylus jasperi | - | 4 | T |
| Coqui, mottled | Eleutherodactylus eneidae | - | 4 | SC |
| Coqui, web-footed | Eleutherodactylus karlschmidti | - | 4 | SC |
| Coral, elkhorn | Acropora palmata | - | NMFS | T |
| Coral, staghorn | Acropora cervicornis | - | NMFS | T |
| Coral-root, Chisos | Hexalectris revoluta | - | 2 | SC |
| Coral-root, Glass Mountain | Hexalectris nitida | - | 2 | SC |
| Coreopsis, Mt. Hamilton | Coreopsis hamiltonii | - | 1 | SC |
| Corkwood | Leitneria floridana | - | 4 | SC |
| cormorant, Double-crested | phalacrocorax auritus | - | 7 | SC |
| Cornsalad, Edwards' Plateau | Valerianella texana | - | 2 | SC |
| Cory cactus, bunched | Coryphantha ramillosa | - | 2 | T |
| Cory cactus, Chaffey's | Coryphantha chaffeyi | - | 2 | SC |
| Cory cactus, Duncan's | Coryphantha duncanii | - | 2 | SC |
| Cory cactus, Hester's | Coryphantha hesteri | - | 2 | SC |
| Cory cactus, Nickel's | Coryphantha sulcata nickelsiae | - | 2 | SC |
| Cory cactus, white column | Coryphantha albicolumnaria | - | 2 | SC |
| Cory cactus, [unnamed] | Coryphantha missouriensis marstonii | - | 2 | RT |
| Cory cactus, [unnamed] | Coryphantha scheeri uncinata | - | 2 | RT |
| Cory cactus, [unnamed] | Coryphantha vivipara buoflama | - | 2 | RT |
| Corydalis, Sierra | Corydalis caseana caseana | - | 1 | RT |
| Cotinga, banded | Cotinga maculata | - | Foreign | E |
| Cotinga, grey-winged | Tijuca condita | - | NA | SU |
| Cotinga, white-winged | Xipholena atropurpurea | - | Foreign | E |
| Cotorrilla | Heliotropium guanicense | - | 4 | RT |
| Cotton rat, Colorado River | Sigmodon arizonae plenus | - | 1 | SC |
| Cotton rat, Hot Springs | Sigmodon fulviventer goldmani | - | 2 | SC |
| Cotton rat, insular hispid | Sigmodon hispidus insulicola | - | 4 | SC |
| Cotton rat, lower Keys | Sigmodon hispidus exsputus | - | 4 | RT |
| Cotton rat, Micco hispid | Sigmodon hispidus littoralis | - | 4 | RT |
| Cotton rat, Yavapai Arizona | Sigmodon arizonae jacksoni | - | 2 | SC |
| Cotton rat, yellow-nosed | Sigmodon ochrognathus | - | 2 | SC |
| Cotton rat, Yuma hispid | Sigmodon hispidus eremicus | - | 2 | SC |
| Cotton, Hawaiian | Gossypium tomentosum | - | 1 | RT |
| Cottonwood, Goat Canyon | Populus hinckleyana | - | 2 | RT |
| Courser, Jerdon's | Rhinoptilus bitorquatus | - | 9 | PE |
| Covert, Clingman | Mesodon clingmanicus | - | 4 | SC |
| Covert, engraved | Mesodon orestes | - | 4 | RT |
| Coyot, bush, Hoover's | Baccharis plummerae glabrata | - | 1 | RT |
| coyote | canis latrans | - | 7 | SC |
| Coyote-thistle, Delta | Eryngium racemosum | - | 1 | SC |
| Coyote-thistle, Mathias' | Eryngium mathiasiae | - | 1 | RT |
| Coyote-thistle, Tuolumne | Eryngium pinnatisectum | - | 1 | SC |
| Coyote-thistle, [unnamed] | Eryngium petiolatum | - | 1 | RT |
| Crabgrass, Florida pineland | Digitaria pauciflora | - | 4 | C |
| Crake, spotless | Porzana tabuensis | American Samoa pop | 1 | C |
| Crane, black-necked | Grus nigricollis | - | Foreign | E |
| Crane, Cuba sandhill | Grus canadensis nesiotes | - | Foreign | E |
| Crane, Greater Sandhill | Grus canadensis tabida | - | 1 | SU |
| crane, Greater sandhill | guiraca caerulea | - | 7 | SC |
| Crane, hooded | Grus monacha | - | Foreign | E |
| Crane, Japanese | Grus japonensis | - | Foreign | E |
| Crane, Mississippi sandhill | Grus canadensis pulla | - | 4 | E |
| Crane, Siberian white | Grus leucogeranus | - | Foreign | E |
| Crane, white-naped | Grus vipio | - | Foreign | E |
| Crane, whooping | Grus americana | U.S.A. (CO, ID, FL, NM, UT, and the western half of Wyoming) | 4 | EXPN |
| Crane, whooping | Grus americana | U.S.A.(AL, AR, GA, IL, IN, IA, KY, LA, MI, MN, MS, MO, NC, OH, SC, TN, VA, WI, WV) | 2 | EXPN |
| Crane, whooping | Grus americana | Entire, except where listed as an experimental population | 2 | E |
| Crawling water beetle, disjunct | Haliplus nitens | - | 2 | SC |
| Crayfish, Albermarle | Procambarus medialis | - | 4 | SC |
| Crayfish, bearded red | Procambarus pogum | - | 4 | SC |
| Crayfish, Big South Fork | Cambarus bouchardi | - | 4 | RT |
| Crayfish, Black Creek | Procambarus pictus | - | 4 | SC |
| Crayfish, Camp Shelby burrowing | Fallicambarus gordoni | - | 4 | UR |
| Crayfish, Carrollton | Procambarus connus | - | 4 | SC |
| Crayfish, cave | Cambarus aculabrum | - | 4 | E |
| Crayfish, cave | Cambarus zophonastes | - | 4 | E |
| Crayfish, Chickamauga | Cambarus extraneus | - | 4 | SC |
| Crayfish, Chowanoke | Orconectes virginiensis | - | 4 | SC |
| Crayfish, Conchas | Orconectes deanae | - | 2 | RT |
| Crayfish, Croatan | Procambarus plumimanus | - | 4 | SC |
| Crayfish, Edisto | Procambarus echinatus | - | 4 | RT |
| Crayfish, French Broad | Cambarus reburrus | - | 4 | SC |
| Crayfish, Greensboro burrowing | Cambarus catagius | - | 4 | RT |
| Crayfish, Hiwassee | Cambarus hiwassensis | - | 4 | SC |
| Crayfish, Indiana | Orconectes indianensis | - | 3 | SC |
| Crayfish, Jackson Prairie | Procambarus barbiger | - | 4 | RT |
| Crayfish, Little River | Cambarus spicatus | - | 4 | RT |
| Crayfish, Little Tennessee | Cambarus georgiae | - | 4 | RT |
| Crayfish, Louisville | Orconectes jeffersoni | - | 4 | SC |
| Crayfish, Mississippi flatwoods | Procambarus cometes | - | 4 | SC |
| Crayfish, Nashville | Orconectes shoupi | - | 4 | E |
| Crayfish, New River riffle | Cambarus chasmodactylus | - | 5 | RT |
| Crayfish, Obey | Cambarus obeyensis | - | 4 | SC |
| Crayfish, Oktibbeha rivulet | Hobbseus orconectoides | - | 4 | SC |
| Crayfish, Palm Springs Cave | Procambarus acherontis | - | 4 | SC |
| Crayfish, Panama City | Procambarus econfinae | - | 4 | SC |
| Crayfish, Parrish | Cambarus parrishi | - | 4 | SC |
| Crayfish, Pee Dee lotic | Procambarus lepidodactylus | - | 4 | SC |
| Crayfish, Saluda | Distocambarus youngineri | - | 4 | SC |
| Crayfish, Shasta | Pacifastacus fortis | - | 8 | E |
| Crayfish, Shelta Cave | Orconectes sp. | - | 4 | SC |
| Crayfish, Shutispear | Procambarus lylei | - | 4 | SC |
| crayfish, Southern cave | orconectes australis ssp. australis | - | 4 | SC |
| Crayfish, spinytail | Procambarus fitzpatricki | - | 4 | SC |
| crayfish, Tallapoosa River | Cambarus englishi | - | 4 | SC |
| Crayfish, [unnamed] | Cambarus batchi | - | 4 | RT |
| Crayfish, [unnamed] | Cambarus miltus | - | 4 | SC |
| Crayfish, [unnamed] | Cambarus tartarus | - | 2 | SC |
| Crayfish, [unnamed] | Cambarus veteranus | - | 5 | SC |
| Crayfish, [unnamed] | Fallicambarus burrisi | - | 4 | SC |
| Crayfish, [unnamed] | Fallicambarus danielae | - | 4 | SC |
| Crayfish, [unnamed] | Fallicambarus gilpini | - | 4 | SC |
| Crayfish, [unnamed] | Fallicambarus harpi | - | 4 | SC |
| Crayfish, [unnamed] | Fallicambarus jeanae | - | 4 | SC |
| Crayfish, [unnamed] | Fallicambarus petilicarpus | - | 4 | SC |
| Crayfish, [unnamed] | Orconectes williamsi | - | 4 | SC |
| Crayfish, [unnamed] | Procambarus ferrugineus | - | 4 | SC |
| Crayfish, [unnamed] | Procambarus lagniappe | - | 4 | RT |
| Crayfish, [unnamed] | Procambarus liberorum | - | 4 | RT |
| Cream cups, Santa Barbara Island | Platystemon californicus ciliatus | - | 1 | SC |
| Creekshell, Carolina | Villosa vaughaniana | - | 4 | SC |
| Creekshell, Kentucky | Villosa ortmanni | - | 4 | SC |
| creeper, Brown | certhia americana | - | 7 | SC |
| Creeper, Hawaii | Oreomystis mana | - | 1 | E |
| Creeper, Molokai | Paroreomyza flammea | - | 1 | E |
| Creeper, Oahu | Paroreomyza maculata | - | 1 | E |
| Crescent, tawny | Phyciodes batesi | - | 3 | SC |
| Crescentspot, Steptoe Valley | Phyciodes cocyta arenacolor | - | 8 | UR |
| Cress, Tahoe yellow | Rorippa subumbellata | - | 8 | C |
| Cricket, Arizona giant sand treader | Daihinibaenetes arizonensis | - | 2 | SC |
| Cricket, Berkeley Ground | Neonemobius eurynotus | - | NA | RT |
| Cricket, Coachella giant sand treader | Macrobaenetes valgum | - | 1 | SC |
| Cricket, Howarth's cave | Caconemobius howarthi | - | 1 | SC |
| Cricket, Jacalitos Jerusalem | Stenopelmatus nigrocapitatus | - | NA | RT |
| Cricket, Kauai thinfooted bush | Thaumatogryllus variegatus | - | 1 | SC |
| Cricket, Kaumana Cave | Caconemobius varius | - | 1 | SC |
| Cricket, Kelso giant sand treader | Macrobaenetes kelsoensis | - | 1 | SC |
| Cricket, Keys scaly | Cycloptilum irregularis | - | 4 | SC |
| Cricket, laricis tree | Oecanthus laricis | - | 3 | SC |
| Cricket, Oahu deceptor bush | Leptogryllus deceptor | - | 1 | SC |
| Cricket, Samwell Cave | Pristoceuthophilus sp. | - | 1 | SC |
| Cricket, Schauinsland's bush | Caconemobius schauinslandi | - | 1 | SC |
| Cricket, Volcanoes cave | Thaumatogryllus cavicola | - | 1 | SC |
| Crocodile, African dwarf | Osteolaemus tetraspis tetraspis | - | Foreign | E |
| Crocodile, African slender-snouted | Crocodylus cataphractus | - | Foreign | E |
| Crocodile, American | Crocodylus acutus | FL pop. | 4 | T |
| Crocodile, American | Crocodylus acutus | Entire, except U.S.A. (FL) | Foreign | E |
| Crocodile, Ceylon mugger | Crocodylus palustris kimbula | - | Foreign | E |
| Crocodile, Congo dwarf | Osteolaemus tetraspis osborni | - | Foreign | E |
| Crocodile, Cuban | Crocodylus rhombifer | - | Foreign | E |
| Crocodile, Morelet's | Crocodylus moreletii | - | Foreign | E |
| Crocodile, mugger | Crocodylus palustris palustris | - | Foreign | E |
| Crocodile, Nile | Crocodylus niloticus | - | Foreign | T |
| Crocodile, Orinoco | Crocodylus intermedius | - | Foreign | E |
| Crocodile, Philippine | Crocodylus novaeguineae mindorensis | - | Foreign | E |
| Crocodile, saltwater | Crocodylus porosus | Entire, except Papua New Guinea and Australia | Foreign | E |
| Crocodile, saltwater | Crocodylus porosus | Australia | Foreign | T |
| Crocodile, Siamese | Crocodylus siamensis | - | Foreign | E |
| Croomia, [unnamed] | Croomia pauciflora | - | 4 | RT |
| crossbill, Red | Loxia curvirostra | - | 4 | SC |
| Crossosoma, Catalina | Crossosoma californicum | - | 1 | RT |
| Croton, Alabama | Croton alabamensis alabamensis | - | 4 | SC |
| Croton, Wiggin's | Croton wigginsii | - | 1 | RT |
| Crow, Hawaiian (='alala) | Corvus hawaiiensis | - | 1 | E |
| Crow, Mariana (=aga) | Corvus kubaryi | - | 1 | E |
| Crow, white-necked | Corvus leucognaphalus | - | 4 | E |
| Crowfoot, Kerr | Ranunculus fascicularis cuneiformis | - | 2 | RT |
| Crownbeard, big-leaved | Verbesina dissita | - | 8 | T |
| Crownbeard, Chapman's | Verbesina chapmannii | - | 4 | SC |
| Crownscale, San Jacinto Valley | Atriplex coronata var. notatior | - | 8 | E |
| Cryptantha, Alpine County | Cryptantha crymophila | - | 1 | RT |
| Cryptantha, Gander's | Cryptantha ganderi | - | 1 | SC |
| Cryptantha, Hoffmann's | Cryptantha hoffmannii | - | 1 | RT |
| Cryptantha, New York Mountains | Cryptantha tumulosa | - | 1 | RT |
| Cryptantha, Schoolcraft's | Cryptantha schoolcraftii | - | 1 | SC |
| Cryptantha, silky | Cryptantha crinita | - | 1 | SC |
| Cryptantha, Trask's | Cryptantha traskiae | - | 1 | SC |
| Cryptantha, Welsh's | Cryptantha welshii | - | 1 | SC |
| Cuckoo, southeastern rufous-vented ground | Neomorphus geoffroyi dulcis | - | Foreign | PE |
| Cuckoo, yellow-billed | Coccyzus americanus | Western U.S. DPS | 8 | C |
| Cuckoo-shrike, Mauritius | Coquus typicus | - | Foreign | E |
| Cuckoo-shrike, Reunion | Coquus newtoni | - | Foreign | E |
| Cuero de sapo | Maytenus elongata | - | 4 | SC |
| Cuero de sapo | Maytenus ponceana | - | 4 | RT |
| Cui-ui | Chasmistes cujus | - | 8 | E |
| Curassow, blue-billed | Crax alberti | - | Foreign | PE |
| Curassow, razor-billed | Mitu mitu mitu | - | Foreign | E |
| Curassow, red-billed | Crax blumenbachii | - | Foreign | E |
| Curassow, Southern-helmeted | Pauxi unicornis | - | Foreign | UR |
| Curassow, Trinidad white-headed | Pipile pipile pipile | - | Foreign | E |
| Curlew, bristle-thighed | Numenius tahitiensis | - | 7 | SC |
| Curlew, Eskimo | Numenius borealis | - | 7 | E |
| Curlew, long-billed | Numenius americanus | - | 6 | RT |
| Curlew, slender-billed | Numenius tenuirostris | - | Foreign | PE |
| Currant, Moreno | Ribes canthariforme | - | 1 | SC |
| Currawong, Lord Howe Island (pied) | Strepera graculina crissalis | - | Foreign | UR |
| Cyanea, Molokai | Cyanea solenocalyx | - | 1 | RT |
| Cycladenia, Jones | Cycladenia jonesii (=humilis) | - | 6 | T |
| Cymopterus, desert | Cymopterus deserticola | - | 1 | RT |
| Cypress, Cuyamaca | Cupressus stephensonii | - | 1 | RT |
| Cypress, Gowen | Cupressus goveniana ssp. goveniana | - | 8 | T |
| Cypress, Mendocino | Cupressus goveniana pigmaea | - | 1 | SC |
| Cypress, Monterey | Cupressus macrocarpa | - | 1 | SC |
| Cypress, Piute | Cupressus nevadensis | - | 1 | RT |
| Cypress, Santa Cruz | Cupressus abramsiana | - | 8 | E |
| Cypress, Tecate | Cupressus forbesii | - | 1 | SC |
| Dace, Amargosa Canyon speckled | Rhinichthys osculus ssp. | Amargosa Canyon | 1 | SC |
| Dace, Ash Meadows speckled | Rhinichthys osculus nevadensis | - | 8 | E |
| Dace, Benton Valley speckled | Rhinichthys osculus ssp. | Benton Valley | 1 | SC |
| Dace, blackside | Phoxinus cumberlandensis | - | 4 | T |
| Dace, Clover Valley speckled | Rhinichthys osculus oligoporus | - | 8 | E |
| Dace, desert | Eremichthys acros | - | 8 | T |
| Dace, Diamond Valley speckled | Rhinichthys osculus ssp. | Diamond Valley | 1 | SC |
| Dace, Foskett speckled | Rhinichthys osculus ssp. | Foskett | 1 | T |
| Dace, Grass Valley speckled | Rhinichthys osculus reliquus | - | 1 | RT |
| Dace, Independence Valley speckled | Rhinichthys osculus lethoporus | - | 8 | E |
| Dace, Kendall Warm Springs | Rhinichthys osculus thermalis | - | 6 | E |
| Dace, Las Vegas | Rhinichthys deaconi | - | 1 | RT |
| dace, Laurel | Phoxinus saylori | - | 4 | PE |
| Dace, Little Lake speckled | Rhinichthys osculus ssp. | Little Lake | 1 | RT |
| Dace, Long Valley speckled | Rhinichthys osculus ssp. | Long Valley | 1 | SC |
| Dace, longfin | Agosia chrysogaster | - | 2 | SC |
| Dace, Meadow Valley Wash speckled | Rhinichthys osculus ssp. | Meadow Valley | 1 | UR |
| Dace, Millicoma | Rhinichthys cataractae ssp. | - | 1 | SC |
| Dace, Moapa | Moapa coriacea | - | 8 | E |
| Dace, Moapa speckled | Rhinichthys osculus moapae | - | 1 | UR |
| Dace, Monitor Valley speckled | Rhinichthys osculus ssp. | Monitor Valley | 1 | SC |
| Dace, Oasis Valley speckled | Rhinichthys osculus ssp. | Oasis Valley | 1 | UR |
| Dace, Owens speckled | Rhinichthys osculus ssp. | Owens | 1 | SC |
| Dace, Pahranagat speckled | Rhinichthys osculus velifer | - | 1 | UR |
| Dace, relict | Relictus solitarius | - | 1 | SC |
| Dace, Santa Ana speckled | Rhinichthys osculus ssp. | Santa Ana | 1 | SC |
| Dace, speckled | Rhinichthys osculus ssp. | Gila & Bill Williams | 2 | SC |
| Dace, White River speckled | Rhinichthys osculus ssp. | White River | 1 | UR |
| Dagger moth, albarufan | Acronicta albarufa | - | 5 | SC |
| Daisy Awapa | Erigeron awapensis | - | 6 | RT |
| Daisy, Abajo | Erigeron abajoensis | - | 6 | RT |
| Daisy, Apalachicola doll's | Boltonia apalachicolensis | - | 4 | SC |
| Daisy, basalt | Erigeron basalticus | - | 1 | RT |
| Daisy, cliff | Erigeron proselyticus | - | 6 | RT |
| Daisy, Cronquist | Erigeron cronquistii | - | 6 | SC |
| Daisy, depauperate | Erigeron mancus | - | 6 | SC |
| Daisy, Hall's | Erigeron aequifolius | - | 1 | RT |
| Daisy, Kachina | Erigeron kachinensis | - | 6 | SC |
| Daisy, Kern River | Erigeron multiceps | - | 1 | SC |
| Daisy, lakeside | Hymenoxys herbacea | - | 3 | T |
| Daisy, Maguire | Erigeron maguirei | - | 6 | T |
| Daisy, Panamint | Enceliopsis covillei | - | 1 | SC |
| Daisy, Parish's | Erigeron parishii | - | 8 | T |
| Daisy, seaside, Coulter's | Lasthenia glabrata coulteri | - | 1 | SC |
| Daisy, supple | Erigeron supplex | - | 1 | SC |
| Daisy, Trinity Alps | Erigeron flexuosus | - | 1 | RT |
| Daisy, Waldo | Erigeron bloomeri nudatus | - | 1 | RT |
| Daisy, Willamette | Erigeron decumbens var. decumbens | - | 1 | E |
| Dalea, Cox's | Dalea bartonii | - | 2 | SC |
| Damselfly, adytum megalagrion | Megalagrion adytum | - | 1 | SC |
| Damselfly, Balmorhea | Argia sp. | Balmorhea | 2 | SC |
| Damselfly, Barrens bluet | Enallagma recurvatum | - | 5 | RT |
| Damselfly, blackline Hawaiian | Megalagrion nigrohamatum nigrolineatum | - | 1 | C |
| Damselfly, crimson Hawaiian | Megalagrion leptodemus | - | 1 | C |
| Damselfly, fallax megalagrion | Megalagrion amaurodytum fallax | - | 1 | RT |
| Damselfly, flying earwig Hawaiian | Megalagrion nesiotes | - | 1 | E |
| Damselfly, jugorum megalagrion | Megalagrion jugorum | - | 1 | RT |
| Damselfly, Molokai megalagrion | Megalagrion molokaiense | - | 1 | SC |
| Damselfly, nigrohamatum megalagrion | Megalagrion nigrohamatum nigrohamatum | - | 1 | SC |
| Damselfly, Oahu megalagrion | Megalagrion oahuenses | - | 1 | SC |
| Damselfly, oceanic Hawaiian | Megalagrion oceanicum | - | 1 | C |
| Damselfly, orangeblack Hawaiian | Megalagrion xanthomelas | - | 1 | C |
| Damselfly, Pacific Hawaiian | Megalagrion pacificum | - | 1 | E |
| Damselfly, Pele megalagrion | Megalagrion amaurodytum peles | - | 1 | SC |
| damselfly, Rota blue | ischnura | - | 6 | SC |
| Damselfly, Sabino Canyon | Argia sp. | Sabino Canyon | 2 | SC |
| Damselfly, San Francisco forktail | Ischnura gemina | - | 1 | RT |
| Damselfly, Waianae megalagrion | Megalagrion amaurodytum waianaeanum | - | 1 | SC |
| Dance fly, Hawaiian chersodromian | Chersodromia hawaiiensis | - | 1 | SC |
| Dancing-lady, Coot Bay | Oncidium carthagenense | - | 4 | RT |
| Dart moth, Buchholz' | Agrotis buchholzi | - | 4 | SC |
| Darter, Alabama channel | Percina sp. | AL channel | 4 | SC |
| Darter, amber | Percina antesella | - | 4 | E |
| Darter, Arkansas | Etheostoma cragini | - | 6 | C |
| Darter, ashy | Etheostoma cinereum | - | 4 | SC |
| darter, bandfin | Etheostoma zonistium | - | 4 | SC |
| Darter, Barrens | Etheostoma forbesi | - | 4 | SC |
| Darter, bayou | Etheostoma rubrum | - | 4 | T |
| Darter, bluemask (=jewel) | Etheostoma sp. | - | 4 | E |
| Darter, bluestripe | Percina cymatotaenia | - | 3 | SC |
| Darter, boulder | Etheostoma wapiti | - | 4 | E |
| Darter, boulder | Etheostoma wapiti | Shoal Creek | 4 | EXPN |
| Darter, bronze | Percina palmaris | - | 4 | RT |
| Darter, Carolina | etheostoma collis | - | 4 | SC |
| Darter, Cherokee | Etheostoma scotti | - | 4 | T |
| Darter, coldwater | Etheostoma ditrema | - | 4 | SC |
| Darter, coppercheek | Etheostoma aquali | - | 4 | SC |
| Darter, crown | Etheostoma corona | - | 4 | SC |
| Darter, Cumberland | Etheostoma susanae | - | 4 | PE |
| Darter, diamond | Crystallaria cincotta | - | 5 | C |
| Darter, duskytail | Etheostoma percnurum | Entire | 4 | E |
| Darter, duskytail | Etheostoma percnurum | Tellico River, between the backwaters of the Tellico Reservoir and the Tellico Ranger Station, in Monroe County, Tennessee | 4 | EXPN |
| Darter, duskytail | Etheostoma percnurum | U.S.A. (TN - specified portions of the French Broad and Holston Rivers; see 17.84(q)(1)(ii)) | 4 | EXPN |
| Darter, eastern sand | Etheostoma pellucidum | - | 5 | SC |
| Darter, egg-mimic | Etheostoma pseudovulatum | - | 4 | SC |
| Darter, Etowah | Etheostoma etowahae | - | 4 | E |
| Darter, finescale saddled | Etheostoma osburni | - | 5 | SC |
| Darter, fountain | Etheostoma fonticola | - | 2 | E |
| Darter, freckled | Percina lenticula | - | 4 | RT |
| Darter, goldline | Percina aurolineata | - | 4 | T |
| Darter, greenthroat | Etheostoma lepidum | - | 2 | RT |
| Darter, Halloween | Percina sp. | Halloween | 4 | SC |
| Darter, Hiwassee | Etheostoma | - | 4 | SU |
| Darter, holiday | Etheostoma brevirostrum | - | 4 | SC |
| Darter, leopard | Percina pantherina | - | 2 | T |
| darter, lipstick | Etheostoma chuckwachatte | - | 4 | SC |
| Darter, longhead | Percina macrocephala | - | 5 | SC |
| Darter, longnose | Percina nasuta | - | 4 | RT |
| Darter, Maryland | Etheostoma sellare | - | 5 | E |
| Darter, Niangua | Etheostoma nianguae | - | 3 | T |
| Darter, Okaloosa | Etheostoma okaloosae | - | 4 | E |
| Darter, olive | Percina squamata | - | 4 | SC |
| Darter, paleback | Etheostoma pallididorsum | - | 4 | RT |
| Darter, Pearl | Percina aurora | - | 4 | C |
| Darter, pinewoods | Etheostoma mariae | - | 4 | RT |
| Darter, relict | Etheostoma chienense | - | 4 | E |
| Darter, Rio Grande | Etheostoma grahami | - | 2 | SC |
| Darter, rock | Etheostoma rupestre | - | 4 | RT |
| Darter, rush | Etheostoma phytophilum | - | 4 | PE |
| Darter, sharphead | Etheostoma acuticeps | - | 5 | RT |
| Darter, slackwater | Etheostoma boschungi | - | 4 | T |
| Darter, snail | Percina tanasi | - | 4 | T |
| Darter, spotted | Etheostoma maculatum | - | 5 | SC |
| Darter, stargazing | Percina uranidea | - | 4 | SC |
| Darter, striated | Etheostoma striatulum | - | 4 | SC |
| Darter, trispot | Etheostoma trisella | - | 4 | SC |
| Darter, Tuckaseegee | Etheostoma blenniodes guttseli | - | 4 | SU |
| Darter, Tuscumbia | Etheostoma tuscumbia | - | 4 | SC |
| Darter, Tuskaloosa | Etheostoma douglasi | - | 4 | SC |
| Darter, vermilion | Etheostoma chermocki | - | 4 | E |
| Darter, waccamaw | Etheostoma perlongum | - | 4 | RT |
| Darter, Warrior | Etheostoma bellator | - | 4 | SC |
| Darter, Warrior bridled | Percina sp. | Warrior bridled | 4 | SC |
| Darter, watercress | Etheostoma nuchale | - | 4 | E |
| Darter, yazoo | Etheostoma sp. | - | 4 | RT |
| Darter, yellowcheek | Etheostoma moorei | - | 4 | PE |
| Dawn-flower, Texas prairie | Hymenoxys texana | - | 2 | E |
| Dayflower, climbing | Commelina gigas | - | 4 | RT |
| Deathcamus, sheathed | Zigadenus vaginatus | - | 1 | RT |
| Deer, Bactrian | Cervus elaphus bactrianus | - | Foreign | E |
| Deer, Barbary | Cervus elaphus barbarus | - | Foreign | E |
| Deer, Blackbeard Island white-tailed | Odocoileus virginianus nigribarbis | - | 4 | SC |
| Deer, Bulls Island white-tailed | Odocoileus virginianus taurinsulae | - | 4 | SC |
| Deer, Calamianes (=Philippine) | Axis porcinus calamianensis | - | Foreign | E |
| Deer, Cedros Island mule | Odocoileus hemionus cerrosensis | - | Foreign | E |
| Deer, Columbian white-tailed | Odocoileus virginianus leucurus | Douglas County, Oregon | 1 | DM |
| Deer, Columbian white-tailed | Odocoileus virginianus leucurus | Columbia River (Clark, Cowliz, Pacific, Skamania, and Wahkiakum Counties, WA., and Clatsop, Columbia, and Multnomah Counties, OR.) | 1 | E |
| Deer, Corsican red | Cervus elaphus corsicanus | - | Foreign | E |
| Deer, Eld's brow-antlered | Cervus eldi | - | Foreign | E |
| Deer, Formosan sika | Cervus nippon taiouanus | - | Foreign | E |
| Deer, Hilton Head white-tailed | Odocoileus virginianus hiltonensis | - | 4 | SC |
| Deer, Hunting Island white-tailed | Odocoileus virginianus venatoria | - | 4 | SC |
| Deer, Indochina hog | Axis porcinus annamiticus | - | Foreign | E |
| Deer, key | Odocoileus virginianus clavium | - | 4 | E |
| Deer, Kuhl's (=Bawean) | Axis porcinus kuhli | - | Foreign | E |
| Deer, marsh | Blastocerus dichotomus | - | Foreign | E |
| Deer, McNeill's | Cervus elaphus macneilii | - | Foreign | E |
| Deer, musk | Moschus spp. (all species) | Afghanistan, Bhutan, Burma, China (Tibet, Yunnan), India, Nepal, Pakistan, Sikkim | Foreign | E |
| Deer, North China sika | Cervus nippon mandarinus | - | Foreign | E |
| Deer, pampas | Ozotoceros bezoarticus | - | Foreign | E |
| Deer, Persian fallow | Dama mesopotamica (=dama m.) | - | Foreign | E |
| Deer, Ryukyu sika | Cervus nippon keramae | - | Foreign | E |
| Deer, Shansi sika | Cervus nippon grassianus | - | Foreign | E |
| Deer, South China sika | Cervus nippon kopschi | - | Foreign | E |
| Deer, swamp | Cervus duvauceli | - | Foreign | E |
| Deer, Visayan | Cervus alfredi | - | Foreign | E |
| Deer, Yarkand | Cervus elaphus yarkandensis | - | Foreign | E |
| Delphinium, Hutchinson's | Delphinium hutchinsonae | - | 1 | SC |
| Desert beauty | Linanthus bellus | - | 1 | RT |
| Desert pink, Dolores | Lygodesmia doloresensis | - | 6 | RT |
| Desert-mallow, Rusby's | Sphaeralcea rusbyi eremicola | - | 1 | SC |
| Desert-parsley, adobe | Lomatium concinnum | - | 6 | SC |
| Desert-parsley, Bradshaw's | Lomatium bradshawii | - | 1 | E |
| Desert-parsley, Day Valley | Lomatium minus | - | 1 | RT |
| Desert-parsley, Greenman's | Lomatium greenmanii | - | 1 | SC |
| Desert-parsley, Hoover's | Lomatium tuberosum | - | 1 | SC |
| Desert-parsley, Lassen | Lomatium ravenii | - | 1 | RT |
| Desert-parsley, red-fruited | Lomatium erythrocarpum | - | 1 | SC |
| Desert-parsley, Slickrock | Lomatium latilobum | - | 6 | RT |
| Desert-parsley, Suksdorf's | Lomatium suksdorfii | - | 1 | SC |
| Desert-parsley, [unnamed] | Lomatium graveolens clarkii | - | 6 | SC |
| Desert-poppy, white bear | Arctomecon merriamii | - | 1 | SC |
| Desert-poppy, [unnamed] | Arctomecon californica | - | 1 | SC |
| Desert-thorn, San Nicolas Island | Lycium verrucosum | - | 1 | RT |
| Desert-thorn, Santa Catalina Island | Lycium hassei | - | 1 | SC |
| Desertsnail, Morongo | Eremarionta morogoana | - | 1 | SC |
| Desertsnail, Thousand Palms | Eremarionta millepalmarum | - | 1 | SC |
| Desertsnail, white | Eremarionta immaculata | - | 1 | SC |
| Dewberry, Wharton's | Rubus whartoniae | - | 4 | SC |
| Dewberry, [unnamed] | Rubus duplaris | - | 2 | RT |
| Dhole | Cuon alpinus | - | Foreign | E |
| Diacyclops, Carolina well | Diacyclops jeannelli putei | - | 4 | SC |
| Diamondflowers, [unnamed] | Hedyotis nigricans pulvinata | - | 4 | SC |
| Dibbler | Antechinus apicalis | - | Foreign | E |
| Dichondra, California | Dichondra donnelliana | - | 1 | RT |
| Dichondra, western | Dichondra occidentalis | - | 1 | RT |
| Diellia, asplenium-leaved | Diellia erecta | - | 1 | E |
| Dipper, American | Cinclus mexicanus unicolor | - | 6 | RT |
| Disc Lake | Discus brunsoni | - | 6 | RT |
| Disc, Cockerell's striate | Discus shemeki cockerelli | - | 6 | SC |
| Disc, marbled | Discus marmorensis | - | 1 | SC |
| disciplina | lycopodium phlegmaria var. | - | 6 | SC |
| Dissanthelium, California | Dissanthelium californicum | - | 1 | SC |
| Ditaxis, California | Ditaxis californica | - | 1 | SC |
| Diving beetle, Bonita | Deronectes neomexicana | - | 2 | SC |
| Diving beetle, curved-foot hygrotus | Hygrotus curvipes | - | 1 | SC |
| Diving beetle, elusive hydroporus | Hydroporus elusivus | - | 5 | SC |
| Diving beetle, fig seed | Desmopachria cenchramis | - | 4 | SC |
| Diving beetle, Folkerts' hydroporus | Hydroporus folkertsi | - | 4 | SC |
| Diving beetle, Leech's skyline | Hydroporus leechi | - | 1 | SC |
| Diving beetle, Mono Lake hygrotus | Hygrotus artus | - | 1 | RT |
| Diving beetle, narrow-foot hygrotus | Hygrotus diversipes | - | 6 | SC |
| Diving beetle, Schwarz' | Laccophilus schwarzi | - | 5 | RT |
| Diving beetle, simple hydroporus | Hydroporus simplex | - | 1 | SC |
| Diving beetle, Spangler's hydroporus | Hydroporus spangleri | - | 6 | SC |
| Diving beetle, Sulphur Springs hydroporus | Hydroporus sulphurius | - | 4 | SC |
| Diving beetle, sylvan hygrotus | Hygrotus sylvanus | - | 3 | SC |
| Diving beetle, Texas cave | Haideoporus texanus | - | 2 | SC |
| Diving beetle, travertine band-thigh | Hygrotus fontinalis | - | 1 | SC |
| Diving beetle, Utah hydroporus | Hydroporus utahensis | - | 6 | SC |
| Diving beetle, wooly hydroporus | Hydroporus hirsutus | - | 1 | SC |
| Dock, Chiricahua | Rumex orthoneurus | - | 2 | RT |
| Dodder Wyoming | Cuscuta plattensis | - | 6 | SC |
| Dodder, Bogg's Lake | Cuscuta howelliana | - | 1 | RT |
| Dodder, Harper's | Cuscuta harperi | - | 4 | SC |
| Dodder, slender | Cuscuta attenuata | - | 2 | SC |
| Dodder, Warner's | Cuscuta warneri | - | 6 | SC |
| Dog, African wild | Lycaon pictus | - | Foreign | E |
| Dogbane, Jones' | Apocynum jonesii | - | 2 | RT |
| Dogweed, ashy | Thymophylla tephroleuca | - | 2 | E |
| Dolly Varden | Salvelinus malma | - | 1 | PSAT |
| Dolphin, Chinese River | Lipotes vexillifer | - | Foreign | E |
| Dolphin, Indus River | Platanista minor | - | Foreign | E |
| Dove, cloven-feathered | Drepanoptila holosericea | - | Foreign | E |
| Dove, Grenada gray-fronted | Leptotila rufaxilla wellsi | - | Foreign | E |
| Dove, Mariana fruit | Ptilinopus roseicapillus | - | 1 | RT |
| Dove, Palau ground | Gallicolumba canifrons | - | Foreign | DM |
| Dovekie | Alle alle | - | NA | RT |
| Downingia, Cuyamac Lake | Downingia concolor brevior | - | 1 | RT |
| Downingia, dwarf | Downingia humilis | - | 1 | RT |
| Draba Wasatch | Draba brachystylis | - | 6 | SC |
| Draba, Bodie Hills | Cusickiella quadricostata | - | 1 | SC |
| Draba, branched | Draba stenoloba ramosa | - | 1 | RT |
| Draba, Crocker's | Draba douglasii crockeri | - | 1 | RT |
| Draba, Cup Lake | Draba asterophora macrocarpa | - | 1 | SC |
| Draba, dolomite | Draba crassifolia nevadensis | - | 1 | SC |
| Draba, Douglas' | Draba douglasii douglasii | - | 1 | RT |
| Draba, Mineral King | Draba cruciata cruciata | - | 1 | RT |
| Draba, Mt. Eddy | Draba carnosula | - | 1 | SC |
| Draba, Mt. Whitney | Draba cruciata integrifolia | - | 1 | RT |
| Draba, snow, little | Draba nivalis brevicula | - | 6 | RT |
| Draba, Sweetwater Mountains | Draba lemmonii incrassata | - | 1 | RT |
| Draba, Tahoe | Draba asterophora asterophora | - | 1 | RT |
| Dragonfly, Big Thicket emerald | Somatochlora margarita | - | 2 | SC |
| Dragonfly, Hine's emerald | Somatochlora hineana | - | 3 | E |
| Dragonfly, Hudson clubtail | Gomphus adelphus | - | 5 | RT |
| Drill | Mandrillus (=Papio) leucophaeus | - | Foreign | E |
| Dropseed, wireleaf | Sporobolus teretifolius | - | 4 | SC |
| Dropseed, [unnamed] | Sporobolus patens | - | 2 | RT |
| Dropwort, Canby's | Oxypolis canbyi | - | 4 | E |
| Dubautia, Knudsen | Dubautia knudsenii knudsenii | - | 1 | RT |
| Duck, fulvous whistling | Dendrocygna bicolor | - | 1 | SC |
| Duck, harlequin | Histrionicus histrionicus | - | 6 | RT |
| Duck, Hawaiian (=koloa) | Anas wyvilliana | - | 1 | E |
| Duck, Laysan | Anas laysanensis | - | 1 | E |
| Duck, long-tailed | Clangula hyemalis | - | 7 | RT |
| Duck, Mexican | Anas diazi | U.S. only | 2 | DR |
| Duck, pink-headed | Rhodonessa caryophyllacea | - | Foreign | E |
| Duck, West Indian ruddy | Oxyura jamaicensis jamaicensis | Puerto Rico | 4 | SC |
| Duck, West Indian whistling | Dendrocygna arborea | Puerto Rico | 4 | SC |
| Duck, white-winged wood | Cairina scutulata | - | Foreign | E |
| Dudleya, candleholder | Dudleya candelabrum | - | 1 | SC |
| Dudleya, Conejo | Dudleya abramsii ssp. parva | - | 8 | T |
| dudleya, Island green | dudleya virens ssp. insularis | - | 1 | SC |
| Dudleya, marcescent | Dudleya cymosa ssp. marcescens | - | 8 | T |
| Dudleya, mouse-leaved | Dudleya abramsii murina | - | 1 | RT |
| Dudleya, Orcutt's | Dudleya attentuata orcuttii | - | 1 | SC |
| Dudleya, Panamint | Dudleya saxosa saxosa | - | 1 | SC |
| Dudleya, San Bernardino Mountains | Dudleya abramsii affinis | - | 1 | SC |
| Dudleya, San Gabriel Mountains | Dudleya densiflora | - | 1 | RT |
| Dudleya, San Gabriel River | Dudleya cymosa crebrifolia | - | 1 | SC |
| Dudleya, San Luis serpentine | Dudleya abramsii bettinae | - | 1 | SC |
| Dudleya, Santa Clara Valley | Dudleya setchellii | - | 8 | E |
| Dudleya, Santa Cruz Island | Dudleya nesiotica | - | 8 | T |
| Dudleya, Santa Rosa Island | Dudleya blochmaniae insularis | - | 1 | RT |
| Dudleya, short-leaved | Dudleya blochmaniae blochmaniae | - | 1 | SC |
| Dudleya, short-leaved | Dudleya blochmaniae brevifolia | - | 1 | RT |
| Dudleya, sp. nov. ined. (munchkin) | Dudleya sp. | - | 1 | RT |
| Dudleya, variegated | Dudleya variegata | - | 1 | SC |
| Dudleya, Verity's | Dudleya verityi | - | 8 | T |
| Dudleyea, Santa Monica Mountains | Dudleya cymosa ssp. ovatifolia | - | 8 | T |
| Dugong | Dugong dugon | Entire, except Palau | Foreign | E |
| Dugong | Dugong dugon | Palau | Foreign | E |
| Duiker, Jentink's | Cephalophus jentinki | - | Foreign | E |
| Dung beetle, Big Pine Key ataenius | Ataenius superficialis | - | 4 | SC |
| Dung beetle, Woodruff's ataenius | Ataenius woodruffi | - | 4 | SC |
| Duskysnail, canary | Lyogyrus spc | - | 8 | SU |
| Duskysnail, Columbia | Lyogyrus sp | - | 1 | SU |
| Duskysnail, masked | Lyogyrus spb | - | 1 | SU |
| Dwarf-flax, Brewer's | Hesperolinon breweri | - | 1 | SC |
| Dwarf-flax, Drymaria | Hesperolinon drymarioides | - | 1 | SC |
| Dwarf-flax, glandular | Hesperolinon adenophyllum | - | 1 | SC |
| Dwarf-flax, Lake County | Hesperolinon didymocarpum | - | 1 | SC |
| Dwarf-flax, Marin | Hesperolinon congestum | - | 8 | T |
| Dwarf-flax, Tehama | Hesperolinon tehamense | - | 1 | SC |
| Dwarf-flax, two carpeled | Hesperolinon bicarpellatum | - | 1 | SC |
| Eagle, bald | Haliaeetus leucocephalus | U.S.A., conterminous (lower 48) States. | 3 | DM |
| Eagle, bald | Haliaeetus leucocephalus | Sonoran Desert DPS: Arizona: (1) Yavapai, northern Mexico. Gila, Graham, Pinal, and Maricopa, Counties; and (2) Southern Mohave County (that portion south and east of the center of Interstate Highway 40 and east of Arizona Highway 95), eastern LaPaz County (that portion east of the centerline of U.S. and Arizona Highways 95), and north of the centerline of Interstate Highway 8). | 2 | T |
| eagle, Golden | aquila chrysaetos | - | 7 | SC |
| Eagle, Greenland white-tailed | Haliaeetus albicilla groenlandicus | - | Foreign | E |
| Eagle, harpy | Harpia harpyja | - | Foreign | E |
| Eagle, Madagascar sea | Haliaeetus vociferoides | - | Foreign | E |
| Eagle, Madagascar serpent | Eutriorchis astur | - | Foreign | E |
| Eagle, Philippine | Pithecophaga jefferyi | - | Foreign | E |
| Eagle, Spanish imperial | Aquila heliaca adalberti | - | Foreign | E |
| earthworm, Giant Palouse | Driloleirus americanus | - | 1 | RT |
| Earthworm, Oregon giant | Megascolides macelfreshi | - | 1 | SC |
| Ebonyshell, round | Fusconaia rotulata | - | 4 | C |
| Eel, American | Anguilla rostrata | - | 5 | RT |
| Egg-vetch, Clokey's | Astragalus oophorus clokeyanus | - | 1 | RT |
| Egret, Chinese | Egretta eulophotes | - | Foreign | E |
| Egret, reddish | Egretta rufescens | - | 4 | SC |
| Eider, spectacled | Somateria fischeri | - | 7 | T |
| Eider, Steller's | Polysticta stelleri | U.S.A. (AK breeding population only) | 7 | T |
| Eland, western giant | Taurotragus derbianus derbianus | - | Foreign | E |
| Elepaio, Oahu | Chasiempis sandwichensis ibidis | - | 1 | E |
| Elephant, African | Loxodonta africana | - | Foreign | T |
| Elephant, Asian | Elephas maximus | - | Foreign | E |
| Elephantear, fluted | Elliptio mcmichaeli | - | 4 | SU |
| Elephantear, St. Johns | Elliptio monroensis | - | 4 | SC |
| Elfin, Marin | Incisalia mossii ssp. | Marin | 1 | SC |
| Elfin, San Gabriel Mountains | Incisalia mossii ssp. | San Gabriel | 1 | SC |
| Elima, black-crest | Elimia albanyensis | - | 4 | SC |
| Elimia, acute | Elimia acuta | - | 4 | SC |
| Elimia, ample | Elimia ampla | - | 4 | RT |
| Elimia, banded | Elimia fascinans | - | 4 | SC |
| Elimia, brook | Elimia strigosa | - | 4 | SC |
| Elimia, Cahaba | Elimia cahawbensis | - | 4 | RT |
| Elimia, caper | Elimia olivula | - | 4 | SC |
| Elimia, coal | Elimia aterina | - | 4 | SC |
| Elimia, cobble | Elimia vanuxemiana | - | 4 | RT |
| Elimia, coldwater | Elimia gerhardti | - | 4 | RT |
| Elimia, compact | Elimia showalteri | - | 4 | RT |
| Elimia, constricted | Elimia impressa | - | 4 | RT |
| Elimia, elegant | Elimia teres | - | 4 | SC |
| Elimia, engraved | Elimia prestriata | - | 4 | SC |
| Elimia, flaxen | Elimia boykiniana | - | 4 | SC |
| Elimia, fusiform | Elimia fusiformis | - | 4 | RT |
| Elimia, gladiator | Elimia hydei | - | 4 | SC |
| Elimia, hearty | Elimia jonesi | - | 4 | RT |
| Elimia, high-spired | Elimia hartmaniana | - | 4 | RT |
| Elimia, knotty | Elimia interrupta | - | 4 | SC |
| Elimia, lacy (snail) | Elimia crenatella | - | 4 | T |
| Elimia, Lily Shoals | Elimia annettae | - | 4 | RT |
| Elimia, mossy | Elimia troostiana | - | 4 | SC |
| Elimia, mud | Elimia alabamensis | - | 4 | SC |
| Elimia, nymph | Elimia porreta | - | 4 | SC |
| Elimia, pupa | Elimia pupaeformis | - | 4 | RT |
| Elimia, puzzle | Elimia varians | - | 4 | SC |
| Elimia, pygmy | Elimia pygmaea | - | 4 | RT |
| Elimia, ribbed | Elimia laeta | - | 4 | RT |
| Elimia, rough-lined | Elimia pilsbryi | - | 4 | RT |
| Elimia, round-rib | Elimia nassula | - | 4 | SC |
| Elimia, short-spire | Elimia brevis | - | 4 | RT |
| Elimia, silt | Elimia haysiana | - | 4 | SC |
| Elimia, slowwater | Elimia interveniens | - | 4 | SC |
| Elimia, spindle | Elimia capillaris | - | 4 | SC |
| Elimia, spring | Elimia pybasi | - | 4 | SC |
| Elimia, squat | Elimia variata | - | 4 | RT |
| Elimia, walnut | Elimia bellula | - | 4 | SC |
| Elktoe, Appalachian | Alasmidonta raveneliana | - | 4 | E |
| Elktoe, Carolina | Alasmidonta robusta | - | 4 | RT |
| Elktoe, Coosa | Alasmidonta maccordi | - | 4 | RT |
| Elktoe, Cumberland | Alasmidonta atropurpurea | - | 4 | E |
| Elktoe, [unnamed] | Alasmidonta marginata | - | 6 | SC |
| Ensatina, large-blotched | Ensatina eschscholtzii klauberi | - | 1 | SC |
| Ensatina, yellow-blotched | Ensatina eschscholtzii croceator | - | 1 | SC |
| Ephedra, funeral | Ephedra funerea | - | 1 | RT |
| Eriastrum, brandegee | Eriastrum brandegeae | - | 1 | SC |
| Erigeron, sp. nov. ined. | Erigeron sp. | - | 6 | SC |
| Ermine moth, chestnut | Argyresthia castaneela | - | 5 | SC |
| Erubia | Solanum drymophilum | - | 4 | E |
| eryngo, Spinysepaled | Eryngium spinosepalum | - | 1 | SC |
| Ethmiid moth, lost | Ethmia monachella | - | 6 | SC |
| Eucnemid beetle, Dohrn's elegant | Paleoxenus dohrni | - | 1 | SC |
| Eulophia | Pteroglossaspis ecristata | - | 4 | SC |
| Eupatorium, Shasta | Eupatorium shastense | - | 1 | RT |
| Evening-primrose, Antioch Dunes | Oenothera deltoides ssp. howellii | - | 8 | E |
| Evening-primrose, Eureka Valley | Oenothera avita ssp. eurekensis | - | 8 | E |
| Evening-primrose, Hardham's | Camissonia hardhamiae | - | 1 | SC |
| Evening-primrose, Klein's | Oenothera kleinii | - | 6 | SC |
| Evening-primrose, Mono Hot Springs | Camissonia sierrae alticola | - | 1 | SC |
| Evening-primrose, Narrowleaf | Oenothera acutissima | - | 6 | RT |
| Evening-primrose, Organ Mountain | Oenothera organensis | - | 2 | SC |
| Evening-primrose, San Benito | Camissonia benitensis | - | 8 | T |
| Evening-primrose, San Clemente Island | Camissonia guadalupensis clementina | - | 1 | SC |
| Evening-primrose, Sierra Valley | Camissonia tanacetifolia quadriperforata | - | 1 | RT |
| Evening-primrose, Wolf's | Oenothera wolfii | - | 1 | SC |
| Evening-primrose, [unnamed] | Camissonia confertiflora | - | 2 | SC |
| Evening-primrose, [unnamed] | Camissonia exilis | - | 2 | RT |
| Evening-primrose, [unnamed] | Camissonia gouldii | - | 6 | RT |
| Evening-primrose, [unnamed] | Camissonia megalantha | - | 1 | SC |
| Evening-primrose, [unnamed] | Camissonia nevadensis | - | 1 | RT |
| Evening-primrose, [unnamed] | Camissonia parryi | - | 6 | RT |
| Evening-primrose, [unnamed] | Camissonia specuicola hesperia | - | 2 | SC |
| Evening-primrose, [unnamed] | Camissonia specuicola specuicola | - | 2 | RT |
| Evening-primrose, [unnamed] | Oenothera pilosella sessilis | - | 4 | SC |
| Evening-primrose, [unnamed] | Oenothera psammophila | - | 1 | SC |
| Evening-star, White-stemmed | Mentzelia albicaulis | - | NA | SU |
| Everlasting, evergreen | Antennaria suffrutescens | - | 1 | RT |
| Fairy shrimp, Conservancy | Branchinecta conservatio | - | 8 | E |
| Fairy shrimp, longhorn | Branchinecta longiantenna | - | 8 | E |
| Fairy shrimp, Riverside | Streptocephalus woottoni | - | 8 | E |
| Fairy shrimp, San Diego | Branchinecta sandiegonensis | - | 8 | E |
| Fairy shrimp, Stone Mountain | Branchinella lithaca | - | 4 | RT |
| Fairy shrimp, vernal pool | Branchinecta lynchi | - | 8 | T |
| Fairypoppy, White | Meconella oregana | - | 1 | SC |
| Falcon, American peregrine | Falco peregrinus anatum | - | 1 | DM |
| Falcon, Arctic peregrine | Falco peregrinus tundrius | - | 7 | DM |
| Falcon, Eurasian peregrine | Falco peregrinus peregrinus | - | Foreign | E |
| Falcon, northern aplomado | Falco femoralis septentrionalis | - | 2 | E |
| Falcon, northern aplomado | Falco femoralis septentrionalis | Southwestern population | 2 | EXPN |
| Falcon, Peregrine | Falco peregrinus | - | 1 | SC |
| falcon, Prairie | falco mexicanus | - | 2 | SC |
| False dragon-head | Physostegia veroniciformis | - | 4 | RT |
| False dragon-head, Correll's | Physostegia correllii | - | 2 | SC |
| False foxglove, [unnamed] | Agalinis stenophylla | - | 4 | RT |
| False indian-mallow | Anoda abutiloides | - | 2 | RT |
| False indigo, [unnamed] | Amorpha ouachitensis | - | 2 | SC |
| False pimpernel, [unnamed] | Lindernia saxicola | - | 4 | RT |
| False sagebrush, Laramie | Sphaeromeria simplex | - | 6 | SC |
| False water penny, Beer's | Acneus beeri | - | 1 | SC |
| False water penny, Burnell's | Acneus burnelli | - | 1 | SC |
| False water penny, Stark's | Alabameubria starki | - | 4 | SC |
| False water penny, variegated | Dicranopselaphus variegatus | - | 3 | SC |
| False-foxglove, auriculate | Tomanthera auriculata | - | 3 | SC |
| False-foxglove, Caddo purple | Tomanthera caddoensis | - | 4 | SC |
| False-foxglove, purple | Tomanthera skinneriana | - | 3 | SC |
| False-foxglove, Shinner's | Tomanthera pseudaphylla | - | 4 | SC |
| False-hellebore, fringed | Veratrum fimbriatum | - | 1 | RT |
| False-lupine, Santa Barbara | Thermopsis macrophylla agnina | - | 1 | SC |
| False-lupine, velvety | Thermopsis macrophylla semota | - | 1 | SC |
| Fameflower, Goodding | Talinum gooddingii | - | 2 | RT |
| Fameflower, limestone | Talinum calcaricum | - | 4 | RT |
| Fameflower, Pinos Altos | Talinum humile | - | 2 | SC |
| Fameflower, rough-seeded | Talinum rugospermum | - | 3 | SC |
| Fameflower, Tepic | Talinum marginatum | - | 2 | SC |
| Fameflower, Tusayan | Talinum validulum | - | 2 | SC |
| Fameflower, [unnamed] | Talinum appalachianum | - | 4 | RT |
| Fameflower, [unnamed] | Talinum mengesii | - | 4 | RT |
| Fameflower, [unnamed] | Talinum okanoganense | - | 1 | RT |
| Fameflower, [unnamed] | Talinum thompsonii | - | 6 | SC |
| Fanshell | Cyprogenia stegaria | U.S.A. (TN - specified portions of the French Broad and Holston Rivers; see 17.85(b)(1)) | 4 | EXPN |
| Fanshell | Cyprogenia stegaria | - | 4 | E |
| Fanshell, western | Cyprogenia aberti | - | 4 | SC |
| Fantail, Guam rufous-fronted | Rhipidura rufifrons uraniae | - | 1 | RT |
| fatmucket, Arkansas | Lampsilis powellii | - | 4 | T |
| Fatmucket, Waccamaw | Lampsilis fullerkati | - | 4 | SC |
| Fawn-lily, Howell's | Erythronium howellii | - | 1 | RT |
| Fawn-lily, Kaweah Lakes | Erythronium grandiflorum pusateri | - | 1 | RT |
| Fawn-lily, lemon colored | Erythronium citrinum rodrickii | - | 1 | SC |
| Fawn-lily, Tuolumne | Erythronium tuolumnense | - | 1 | SC |
| Fawnsfoot, Mexican | Truncilla cognata | - | 2 | UR |
| Fawnsfoot, Texas | Truncilla macrodon | - | 2 | UR |
| Feathergrass, Porter's | Ptilagrostis porteri | - | 6 | UR |
| Fern cloak, Lemmon | Notholaena lemmonii | - | 2 | SC |
| Fern, Alabama streak-sorus | Thelypteris pilosa var. alabamensis | - | 4 | T |
| Fern, Aleutian shield | Polystichum aleuticum | - | 7 | E |
| Fern, American hart's-tongue | Asplenium scolopendrium var. americanum | - | 4 | T |
| Fern, Canyon lip | Cheilanthes arizonica californicum | - | 2 | RT |
| Fern, curly-grass | Schizaea germanii | - | 4 | RT |
| Fern, curly-grass | Schizaea pusilla | - | 5 | RT |
| Fern, Elfin tree | Cyathea dryopteroides | - | 4 | E |
| fern, Florida bristle | Trichomanes punctatum ssp. floridanum | - | 4 | C |
| Fern, hairy halberd | Tectaria coriandrifolia | - | 4 | SC |
| fern, Maui | Microlepia strigosa var. mauiensis | - | 1 | C |
| Fern, pendant kihi | Adenophorus periens | - | 1 | E |
| Fern, Pringle lip | Cheilanthes pringlei insulare | - | 2 | RT |
| Fern, Tunbridge | Hymenophyllum tunbrigense | - | 4 | SC |
| Fernbird, Codfish Island | Bowdleria punctata wilsoni | - | Foreign | UR |
| Ferret, black-footed | Mustela nigripes | Entire, except where listed as an experimental population below | 6 | E |
| Ferret, black-footed | Mustela nigripes | U.S.A. (specific portions of AZ, CO, MT, SD, UT, and WY, see 17.84(g)) | 6 | EXPN |
| Fescue, Guadalupe | Festuca ligulata | - | 2 | C |
| Fescue, sedge | Festuca dasyclada | - | 6 | RT |
| Fetid-marigold, Rusby's | Pectis rusbyi | - | 2 | RT |
| Feverfew, Arkansas River | Parthenium tetraneuris | - | 6 | SC |
| Feverfew, [unnamed] | Parthenium ligulatum | - | 6 | RT |
| Fiddleneck, forked | Amsinckia vernicosa furcata | - | 1 | SC |
| Fiddleneck, green | Amsinckia vernicosa | - | 1 | RT |
| Fiddleneck, large-flowered | Amsinckia grandiflora | - | 8 | E |
| Fiddleneck, Malheur Valley | Amsinckia carinata | - | 1 | RT |
| fieldslug, Evening | Deroceras hesperium | - | 1 | SU |
| Figwort, black-flowered | Scrophularia atrata | - | 1 | SC |
| Figwort, Organ Mountain | Scrophularia laevis | - | 2 | SC |
| Figwort, Santa Catalina | Scrophularia villosa | - | 1 | SC |
| Figwort, [unnamed] | Scrophularia macrantha | - | 2 | RT |
| filaree, Large-leaved | erodium macrophyllum | - | 6 | SC |
| Fimbristylis, Harper's | Fimbristylis perpusilla | - | 5 | SC |
| Fimbristylis, hot springs | Fimbristylis spadicea | - | 1 | RT |
| Finch, Laysan (honeycreeper) | Telespyza cantans | - | 1 | E |
| Finch, Nihoa (honeycreeper) | Telespyza ultima | - | 1 | E |
| Fir, Fraser | Abies fraseri | - | 4 | SC |
| Fir, Guatemalan (=pinabete) | Abies guatemalensis | - | Foreign | T |
| Fire-eye, fring-backed | Pyriglena atra | - | Foreign | PE |
| Firefly, Everglades brownwing | Photuris brunnipennis floridana | - | 4 | SC |
| Firefly, Florida intertidal | Micronaspis floridana | - | 4 | SC |
| Firefly, Turtle Mound | Photuris sp. | - | 4 | SC |
| Fireweed, Oregon | Epilobium oreganum | - | 1 | SC |
| Fisher | Martes pennanti | West coast DPS | 8 | C |
| Fisher | Martes pennanti | Northern Rocky Mountains DPS | 6 | UR |
| Fisher, Pacific | Martes pennanti pacifica | - | 1 | UR |
| Fishhook cactus, Blaine's | Sclerocactus blainei | - | 1 | SC |
| Fishhook cactus, Great Basin | Sclerocactus pubispinus | - | 6 | RT |
| Fishhook cactus, Mojave | Sclerocactus polyancistrus | - | 1 | RT |
| Fishhook cactus, Schleser's | Sclerocactus schleseri | - | 1 | SC |
| Flamingo, Andean | Phoenicoparrus andinus | - | Foreign | PE |
| Flannelbush, Mexican | Fremontodendron mexicanum | - | 8 | E |
| Flannelbush, Pine Hill | Fremontodendron californicum ssp. decumbens | - | 8 | E |
| flatsedge, Fragrant | Cyperus odoratus | - | 1 | RT |
| flatworm, (Sphalloplana mohri) | sphalloplana mohri | - | 6 | SC |
| Flax, Carter's small-flowered | Linum carteri carteri | - | 4 | C |
| Flax, sand | Linum arenicola | - | 4 | C |
| Flax, West's | Linum westii | - | 4 | SC |
| Flax, [unnamed] | Linum carteri smallii | - | 4 | SC |
| Flax, [unnamed] | Linum macrocarpum | - | 4 | SC |
| Fleabane, Acoma | Erigeron acomanus | - | 2 | SC |
| Fleabane, branched | Erigeron allocotus | - | 6 | RT |
| Fleabane, Chiricahua | Erigeron kuschei | - | 2 | SC |
| Fleabane, Clear Creek | Erigeron religiosus | - | 6 | RT |
| Fleabane, Del Norte | Erigeron delicatus | - | 1 | RT |
| Fleabane, Fish Creek | Erigeron piscaticus | - | 2 | SC |
| Fleabane, Gorge | Erigeron oreganus | - | 1 | SC |
| Fleabane, Hess's | Erigeron hessii | - | 2 | SC |
| Fleabane, Howell's | Erigeron howellii | - | 1 | SC |
| Fleabane, Lemmon | Erigeron lemmonii | - | 2 | C |
| Fleabane, Mogollon | Erigeron anchana | - | 2 | SC |
| Fleabane, Pinalenos | Erigeron heligraphicus | - | 2 | SC |
| Fleabane, Sonora | Erigeron mimegletes | - | 2 | SC |
| Fleabane, Zuni | Erigeron rhizomatus | - | 2 | T |
| Fleabane, [unnamed] | Erigeron calvus | - | 1 | RT |
| Fleabane, [unnamed] | Erigeron eriophyllus | - | 2 | RT |
| Fleabane, [unnamed] | Erigeron latus | - | 1 | SC |
| flicker, Gilded | colaptes chrysoides | - | 6 | SC |
| Floater, brook | Alasmidonta varicosa | - | 5 | SC |
| Floater, California | Anodonta californiensis | - | 2 | RT |
| Floater, green | Lasmigona subviridis | - | 5 | SC |
| Flower fly, Delong's mixogaster | Mixogaster delongi | - | 4 | SC |
| flower Stonecrop Gily | Gilia sedifolia | - | 6 | SC |
| Fly, Belkin's dune tabanid | Brennania belkini | - | 1 | RT |
| Fly, Delhi Sands flower-loving | Rhaphiomidas terminatus abdominalis | - | 8 | E |
| Fly, El Segundo flower-loving | Rhaphiomidas terminatus terminatus | - | 1 | RT |
| Fly, Hawaiian picture-wing | Drosophila digressa | - | 1 | C |
| Fly, Hawaiian picture-wing | Drosophila sharpi | - | 1 | E |
| Fly, Valley mydas | Drosophila alsophila | - | 1 | RT |
| Fly, Valley mydas | Drosophila psilotarsalis | - | 1 | RT |
| Fly, Valley mydas | Drosophila toxochaeta | - | 1 | RT |
| Fly, Valley mydas | Rhaphiomidas trochilus | - | 1 | RT |
| flycatcher, Brown-crested | myiarchus tyrannulus | - | 6 | SC |
| Flycatcher, buff-breasted | Empidonax fulvifrons pygmaeus | - | 2 | UR |
| Flycatcher, Caerulean Paradise | Eutrichomyias rowleyi | - | Foreign | E |
| Flycatcher, Euler's | Empidonax euleri johnstonei | - | Foreign | E |
| Flycatcher, little willow | Empidonax traillii brewsteri | - | 1 | SC |
| Flycatcher, olive-sided | Contopus cooperi | - | 7 | SC |
| Flycatcher, Palau fantail | Rhipidura lepida | - | Foreign | DM |
| Flycatcher, Seychelles paradise | Terpsiphone corvina | - | Foreign | E |
| Flycatcher, southwestern willow | Empidonax traillii extimus | - | 2 | E |
| Flycatcher, Tahiti | Pomarea nigra | - | Foreign | E |
| flycatcher, Vermillion | pyrocephalus rubinus | - | 6 | SC |
| flycatcher, Willow | empidonax dfghsgh | - | 7 | SC |
| Fody, Mauritius | Foudia rubra | - | Foreign | E |
| Fody, Rodrigues | Foudia flavicans | - | Foreign | E |
| Fody, Seychelles (weaver-finch) | Foudia sechellarum | - | Foreign | E |
| Footsteps of spring | Sanicula arctopoides | - | 1 | SC |
| Forkshell | Epioblasma lewisi | - | 4 | RT |
| Forsellesia, Clokey's | Forsellesia clokeyi | - | 1 | SC |
| Forsellesia, smooth pungent | Glossopetalon pungens glabra | - | 1 | SC |
| Four-o'clock, MacFarlane's | Mirabilis macfarlanei | - | 1 | T |
| Four-o'clock, roundleaf | Mirabilis rotundifolia | - | 6 | SC |
| Four-o'clock, sandhill | Mirabilis collina | - | 2 | SC |
| Four-o'clock, [unnamed] | Mirabilis pudica | - | 1 | RT |
| fox, Gray | urocyon cinereoargenteus | - | 2 | SC |
| Fox, island | Urocyon littoralis | - | 1 | SU |
| Fox, northern swift | Vulpes velox hebes | Canada | Foreign | E |
| Fox, San Clemente Island | Urocyon littoralis clementae | - | 1 | SC |
| Fox, San Joaquin kit | Vulpes macrotis mutica | - | 8 | E |
| Fox, San Miguel Island | Urocyon littoralis littoralis | - | 8 | E |
| Fox, San Nicolas Island | Urocyon littoralis dickeyi | - | 1 | SC |
| Fox, Santa Catalina Island | Urocyon littoralis catalinae | - | 8 | E |
| Fox, Santa Cruz Island | Urocyon littoralis santacruzae | - | 8 | E |
| Fox, Santa Rosa Island | Urocyon littoralis santarosae | - | 8 | E |
| Fox, Sierra Nevada red | Vulpes vulpes necator | - | 1 | SC |
| Fox, Simien | Canis simensis | - | Foreign | E |
| Fox, swift | Vulpes velox | U.S. pop. | 6 | RT |
| Foxtail cactus, Alverson's | Coryphantha vivipara alversonii | - | 1 | SC |
| Foxtail cactus, rose-flowered | Coryphantha vivipara rosea | - | 1 | RT |
| Francolin, Djibouti | Francolinus ochropectus | - | Foreign | E |
| Frankenia, Johnston's | Frankenia johnstonii | - | 2 | E |
| Franklin tree | Franklinia alatamaha | - | 4 | SC |
| Freira | Pterodroma madeira | - | Foreign | E |
| Frigatebird, Andrew's | Fregata andrewsi | - | Foreign | E |
| Fringe-tree, pygmy | Chionanthus pygmaeus | - | 4 | E |
| Fringepod, Santa Cruz Island | Thysanocarpus conchuliferus | - | 8 | E |
| Fritillary, Atossa | Speyeria adiaste atossa | - | 1 | RT |
| Fritillary, Butte | Fritillaria eastwoodiae | - | 1 | SC |
| Fritillary, Diana | Speyeria diana | - | 4 | SC |
| Fritillary, fragrant | Fritillaria liliacea | - | 1 | SC |
| Fritillary, Gentner's | Fritillaria gentneri | - | 1 | E |
| Fritillary, Greenhorn | Fritillaria brandegei | - | 1 | RT |
| Fritillary, regal | Speyeria idalia | - | 5 | SC |
| Fritillary, Roderick's | Fritillaria grayana | - | 1 | RT |
| Fritillary, San Benito | Fritillaria viridea | - | 1 | SC |
| Fritillary, talus | Fritillaria falcata | - | 1 | SC |
| Fritillary, unsilvered | Speyeria adiaste | - | 8 | UR |
| Frog, California red-legged | Rana draytonii | Entire | 8 | T |
| Frog, Carolina crawfish | Rana areolata capito | - | 4 | SC |
| Frog, Cascades | Rana cascadae | - | 1 | SC |
| Frog, Chiricahua leopard | Rana chiricahuensis | - | 2 | T |
| Frog, Columbia spotted | Rana luteiventris | Great Basin DPS | 8 | C |
| Frog, Columbia spotted | Rana luteiventris | main pop. | 6 | SC |
| Frog, duckwater | Rana sp. | - | 1 | RT |
| Frog, dusky crawfish | Rana areolata sevosa | - | 4 | SC |
| Frog, Florida bog | Rana okaloosae | - | 4 | SC |
| Frog, Florida crawfish | Rana areolata aesopus | - | 4 | SC |
| Frog, foothill yellow-legged | Rana boylii | - | 1 | SC |
| Frog, Goliath | Conraua goliath | - | Foreign | T |
| Frog, Illinois Strecker's chorus | Pseudacris streckeri illinoensis | - | 3 | SC |
| Frog, Israel painted | Discoglossus nigriventer | - | Foreign | E |
| Frog, lowland leopard (=San Felipe leopard) | Rana yavapaiensis | - | 2 | SC |
| Frog, Mississippi gopher | Rana capito sevosa | Wherever found west of Mobile and Tombigbee Rivers in AL, MS, and LA | 4 | E |
| Frog, mountain yellow-legged | Rana muscosa | U.S.A., all mountain yellow-legged frogs that occur north of the Tehachapi Mountains in the Sierra Nevada | 8 | C |
| Frog, mountain yellow-legged | Rana muscosa | U.S.A., southern California DPS | 8 | E |
| frog, northern leopard | Rana pipiens | - | 6 | SU |
| frog, northern leopard | Rana pipiens | western United States | 6 | UR |
| Frog, northern red-legged | Rana aurora aurora | - | 1 | SC |
| Frog, Oregon spotted | Rana pretiosa | - | 1 | C |
| Frog, Panamanian golden | Atelopus varius zeteki | - | Foreign | E |
| Frog, Ramos bromeliad | Eleutherodactylus ramosi | - | 4 | RT |
| Frog, Ramsey Canyon leopard | Rana subaquavocalis | - | 2 | RT |
| Frog, relict leopard | Rana onca | - | 8 | C |
| Frog, Stephen Island | Leiopelma hamiltoni | - | Foreign | E |
| Frog, tailed | Ascaphus truei | - | 1 | SC |
| Frog, Tarahumara | Rana tarahumarae | - | 2 | SC |
| Frog, Vegas Valley leopard | Rana fisheri | - | 2 | RT |
| Frtillary, Ojai | Fritillaria ojaiensis | - | 1 | SC |
| Fruit-Dove, Many-colored | Ptilinopus perousii perousii | - | 1 | RT |
| Fryxell wort, small | Fryxellia pygmaea | - | 2 | SC |
| Gall fly, Po'olanui | Phaeogramma sp. | - | 1 | RT |
| Gall moth, Busck's | Carolella busckana | - | 1 | SC |
| Gama grass, [unnamed] | Tripsacum floridanum | - | 4 | SC |
| Gambusia, Amistad | Gambusia amistadensis | - | 2 | D3A |
| Gambusia, Big Bend | Gambusia gaigei | - | 2 | E |
| Gambusia, blotched | Gambusia senilis | - | 2 | SC |
| Gambusia, Clear Creek | Gambusia heterochir | - | 2 | E |
| Gambusia, Pecos | Gambusia nobilis | - | 2 | E |
| Gambusia, San Felipe | Gambusia clarkhubbsi | - | 2 | RT |
| Gambusia, San Marcos | Gambusia georgei | - | 2 | E |
| Gardenia (=Na`u), Hawaiian | Gardenia brighamii | - | 1 | E |
| gartersnake, northern Mexican | Thamnophis eques megalops | - | 2 | C |
| Gavial | Gavialis gangeticus | - | Foreign | E |
| Gay-feather, slender | Liatris tenuis | - | 2 | SC |
| Gay-mallow, purple | Batesimalva violacea | - | 2 | SC |
| Gazelle, Arabian | Gazella gazella | - | Foreign | E |
| Gazelle, Clark's | Ammodorcas clarkei | - | Foreign | E |
| Gazelle, dama | Gazella dama | - | Foreign | E |
| Gazelle, Mhorr | Gazella dama mhorr | - | Foreign | E |
| Gazelle, Moroccan | Gazella dorcas massaesyla | - | Foreign | E |
| Gazelle, mountain (=Cuvier's) | Gazella cuvieri | - | Foreign | E |
| Gazelle, Pelzeln's | Gazella dorcas pelzelni | - | Foreign | E |
| Gazelle, Rio de Oro Dama | Gazella dama lozanoi | - | Foreign | E |
| Gazelle, sand | Gazella subgutturosa marica | - | Foreign | E |
| Gazelle, Saudi Arabian | Gazella dorcas saudiya | - | Foreign | E |
| Gazelle, slender-horned | Gazella leptoceros | - | Foreign | E |
| Gecko, barefoot | Coleonyx switaki | - | 1 | SC |
| Gecko, day | Phelsuma edwardnewtoni | - | Foreign | E |
| Gecko, Monito | Sphaerodactylus micropithecus | - | 4 | E |
| Gecko, reticulated | Coleonyx reticulatus | - | 2 | RT |
| Gecko, Round Island day | Phelsuma guentheri | - | Foreign | E |
| Gecko, San Diego banded | Coleonyx variegatus abbotti | - | 1 | SC |
| Gecko, Serpent Island | Cyrtodactylus serpensinsula | - | Foreign | T |
| Gentian, Klamath | Gentiana plurisetosa | - | 1 | SC |
| Gentian, Mendocino | Gentiana setigera | - | 1 | SC |
| Gentian, moss | Gentiana fremontii | - | 1 | RT |
| Gentian, pine barren | Gentiana autumnalis | - | 5 | RT |
| Gentian, wiregrass | Gentiana pennelliana | - | 4 | SC |
| Gentian, [unnamed] | Gentiana deloachii | - | 4 | RT |
| Geometrid moth, Fraser fir | Semiothisa fraserata | - | 4 | SC |
| Geranium, Hawaiian red-flowered | Geranium arboreum | - | 1 | E |
| Geranium, native | Geranium cuneatum hololeucum | - | 1 | RT |
| Geranium, [unnamed] | Geranium marginale | - | 6 | RT |
| Geranium, [unnamed] | Geranium toquimense | - | 1 | RT |
| Gerardia, sandplain | Agalinis acuta | - | 5 | E |
| Ghost moth, [unnamed] | Hepialus sciophanes | - | 4 | SC |
| Gibbons | Hylobates spp. (including Nomascus) | - | Foreign | E |
| Gila monster, banded | Heloderma suspectum cinctum | - | 1 | SC |
| Gilia, beautiful | Aliciella formosa | - | 2 | SC |
| Gilia, Hoffmann's slender-flowered | Gilia tenuiflora ssp. hoffmannii | - | 8 | E |
| Gilia, Little San Bernardino Mountains | Gilia maculata | - | 1 | SC |
| Gilia, Little San Bernardino Mountains | Linanthus maculates | - | 1 | SU |
| Gilia, Monterey | Gilia tenuiflora ssp. arenaria | - | 8 | E |
| Ginseng, American | Panax quinquefolius | - | 3 | RT |
| Glade cress, Alabama | Leavenworthia alabamica ssp. alabamica | - | 4 | RT |
| Glade cress, golden | Leavenworthia aurea | - | 2 | RT |
| Glade cress, Kentucky | Leavenworthia exigua laciniata | - | 4 | C |
| Glade cress, [unnamed] | Leavenworthia alabamica brachystyla | - | 4 | RT |
| Glade cress, [unnamed] | Leavenworthia crassa elongata | - | 4 | SC |
| Glade cress, [unnamed] | Leavenworthia exigua lutea | - | 4 | SC |
| Gladecress, necklace | Leavenworthia torulosa | - | 4 | RT |
| Gladecress, Texas golden | Leavenworthia texana | - | 2 | C |
| Gladecress, [unnamed] | Leavenworthia crassa | - | 4 | C |
| Globe berry, lemmon | Margaranthus lemmonii | - | 2 | SC |
| Globe-lily, The Cedars | Calochortus raichei | - | 1 | SC |
| Globe-mallow, Jones' | Sphaeralcea caespitosa | - | 1 | SC |
| Globe-mallow, Kankakee | Iliamna remota | - | 3 | SC |
| Globe-mallow, [unnamed] | Sphaeralcea fendleri albescens | - | 2 | RT |
| Globeberry, Tumamoc | Tumamoca macdougalii | - | 2 | DP |
| Glyph, blind | Glyphyalinia pecki | - | 4 | SC |
| Glyph, Maryland | Glyphyalinia raderi | - | 5 | SC |
| Gnatcatcher, black-tailed | Polioptila melanura californica | - | 1 | SU |
| Gnatcatcher, coastal California | Polioptila californica californica | - | 8 | T |
| Goats beard, Roan Mountain false | Astilbe crenatiloba | - | 4 | SC |
| Goby, tidewater | Eucyclogobius newberryi | Entire | 8 | E |
| Goetzea, beautiful | Goetzea elegans | - | 4 | E |
| Gold, July | Dedeckera eurekensis | - | 1 | SC |
| Golden aster, Jones | Heterotheca jonesii | - | 6 | RT |
| Golden carpet | Gilmania luteola | - | 1 | RT |
| Goldenbush | Isocoma arguta | - | 1 | SC |
| Goldenbush, Palmer's | Ericameria palmeri ssp. palmeri | - | 1 | SU |
| Goldeneye, field | Helianthus ludens | - | 2 | RT |
| goldenrod Greenwood's Heath | Ericameria lignumviridis | - | 6 | SC |
| Goldenrod, Blue Ridge | Solidago spithamaea | - | 4 | T |
| Goldenrod, Carolina | Solidago pulchra | - | 4 | SC |
| Goldenrod, Engelmann's | Haplopappus engelmannii | - | 6 | SC |
| Goldenrod, Houghton's | Solidago houghtonii | - | 3 | T |
| Goldenrod, Porter's | Solidago porteri | - | 4 | SC |
| Goldenrod, Short's | Solidago shortii | - | 4 | E |
| Goldenrod, spring-flowering | Solidago verna | - | 4 | SC |
| Goldenrod, white-haired | Solidago albopilosa | - | 4 | T |
| Goldenrod, Yadkin River | Solidago plumosa | - | 4 | C |
| Goldenseal | Hydrastis canadensis | - | 4 | RT |
| Goldenstar, dwarf | Bloomeria humilis | - | 1 | SC |
| Goldenstar, San Diego | Muilla clevelandii | - | 1 | SC |
| Goldenweed, Eastwood's | Ericameria fasciculata | - | 1 | SC |
| Goldenweed, small-headed | Haplopappus microcephalus | - | 2 | SC |
| Goldenweed, [unnamed] | Haplopappus contractus | - | 6 | RT |
| Goldenweed, [unnamed] | Haplopappus fremontii monocephalus | - | 6 | RT |
| Goldenweed, [unnamed] | Haplopappus radiatus | - | 1 | SC |
| Goldenweed, [unnamed] | Haplopappus salicinus | - | 2 | RT |
| Goldfields, Burke's | Lasthenia burkei | - | 8 | E |
| Goldfields, Contra Costa | Lasthenia conjugens | - | 8 | E |
| Goldfields, seaside | Lasthenia minor maritima | - | 1 | RT |
| Goose, Aleutian Canada | Branta canadensis leucopareia | - | 7 | DM |
| Goose, Hawaiian | Branta (=Nesochen) sandvicensis | - | 1 | E |
| Goose, Tule white-fronted | Anser albifrons elgasi | - | 7 | RT |
| Gooseberry, Miccosukee | Ribes echinellum | - | 4 | T |
| Gooseberry, Parish's | Ribes divaricatum parishii | - | 1 | SC |
| Gooseberry, Santa Cruz | Ribes thacherianum | - | 1 | SC |
| Gooseberry, Sequoia | Ribes tularensis | - | 1 | SC |
| Goosefoot, Molokai | Chenopodium pekeloi | - | 1 | RT |
| Goosefoot, sandhill | Chenopodium cycloides | - | 6 | SC |
| Goral | Naemorhedus goral | - | Foreign | E |
| Gorilla | Gorilla gorilla | - | Foreign | E |
| Goshawk, Christmas Island | Accipiter fasciatus natalis | - | Foreign | E |
| Goshawk, northern | Accipiter gentilis | - | 2 | RT |
| Goshawk, Queen Charlotte | Accipiter gentilis laingi | British Columbia Population | Foreign | PE |
| Gourd, Okeechobee | Cucurbita okeechobeensis ssp. okeechobeensis | - | 4 | E |
| Grackle, slender-billed | Quisicalus palustris | - | Foreign | E |
| Grap fern, Crater Lake | Botrychium pumicola nealleyi | - | 1 | SC |
| grapplinghook, Palmer's | Harpagonella palmeri | - | 1 | SC |
| Grapplinghook, Palmer's | Harpagonella palmeri palmeri | - | 1 | SC |
| grass of Parnassus, Largeleaf | Parnassia grandifolia | - | 4 | SC |
| grass Tushar Mountain Whitlow | Draba ramulosa | - | 6 | SC |
| grass Weber's Whitlow | Draba weberi | - | 6 | UR |
| Grass, bald | Sporobolus ozarkanus | - | 3 | RT |
| Grass, Colusa | Neostapfia colusana | - | 8 | T |
| Grass, cutthroat | Panicum abscissum | - | 4 | SC |
| Grass, Eureka Dune | Swallenia alexandrae | - | 8 | E |
| Grass, pale blue-eyed | Sisyrinchium pallidum | - | 6 | SC |
| Grass, Solano | Tuctoria mucronata | - | 8 | E |
| Grass, Tennessee yellow-eyed | Xyris tennesseensis | - | 4 | E |
| Grass, Texas windmill | Chloris texensis | - | 2 | SC |
| Grass-of-parnassus, Carolina | Parnassia caroliniana | - | 4 | SC |
| Grass-of-parnassus, Kotzebue's, | Parnassia kotzebuei pumila | - | 1 | RT |
| Grasshopper, Big Cedar | Eximacris phenax | - | 2 | SC |
| Grasshopper, Central Valley | Conozoa hyalina | - | NA | RT |
| Grasshopper, desert monkey | Psychomastix deserticola | - | 1 | SC |
| Grasshopper, Idaho pointheaded | Acrolophitus pulchellus | - | 1 | SC |
| Grasshopper, Lompoc | Trimerotropis occulens | - | NA | RT |
| Grasshopper, Mexicali Lubber | Spaniacris destricola | - | NA | RT |
| Grasshopper, Michigan bog | Appalachia arcana | - | 3 | SC |
| Grasshopper, Pinaleno monkey | Eumorsea pinaleno | - | 2 | SC |
| Grasshopper, San Bernardino Mountains | Trimerotropis bernardi | - | NA | RT |
| Grasshopper, Santa Monica Mountains | Trimerotropis occidentaloides | - | NA | RT |
| Grasshopper, Sierra pygmy | Tetrix sierrana | - | 1 | SC |
| Grasshopper, Siskiyou chloealtis | Chloealtis aspasma | - | 1 | SC |
| Grasshopper, superb | Eximacris superbum | - | 2 | SC |
| Grasshopper, Torreya pygmy | Tettigidea empedonepia | - | 4 | SC |
| Grasshopper, Zayante band-winged | Trimerotropis infantilis | - | 8 | E |
| Grasspink, manyflower | Calopogon multiflorus | - | 4 | SU |
| grasspink, Oklahoma | Calopogon oklahomensis | - | 3 | SU |
| Grasswren, Eyrean (flycatcher) | Amytornis goyderi | - | Foreign | E |
| Grayling, Fluvial arctic | Thymallus arcticus | Upper Missouri River DPS | 6 | RT |
| greasebush, Clokey | glossopetalon clokeyi | - | 6 | SC |
| Greasebush, Texas | Forsellesia texensis | - | 2 | SC |
| Grebe, Alaotra | Tachybaptus rufolavatus | - | Foreign | E |
| Grebe, Atitlan | Podilymbus gigas | - | Foreign | E |
| Grebe, Columbian | Podiceps andinus | - | Foreign | UR |
| Grebe, Junin | Podiceps taczanowskii | - | Foreign | PE |
| grebe, Western | aechmophorus occidentalis | - | 7 | SC |
| Green-gentian, Umpqua | Frasera umpquaensis | - | 1 | SC |
| Green-gentian, [unnamed] | Frasera gypsicola | - | 1 | RT |
| Green-gentian, [unnamed] | Frasera pahutensis | - | 1 | SC |
| Greenshank, Nordmann's | Tringa guttifer | - | Foreign | E |
| Greensword | Argyroxiphium virescens | - | 1 | RT |
| Groovebur, incised | Agrimonia incisa | - | 4 | SC |
| ground beetle, (Bembidion gordoni) | bembidion gordoni | - | 8 | SC |
| ground beetle, (Bembidion stillaguamish) | bembidion stillaguamish | - | 8 | SC |
| ground beetle, (Bembidion viator) | bembidion viator | - | 8 | SC |
| ground beetle, (Bradycellus fenderi) | bradycellus fenderi | - | 8 | SC |
| ground beetle, (Nebria gebleri cascadensis) | nebria gebleri ssp. cascadensis | - | 6 | SC |
| ground beetle, (Nebria kincaidi balli) | nebria kincaidi ssp. balli | - | 6 | SC |
| ground beetle, (Nebria paradisi) | nebria paradisi | - | 6 | SC |
| ground beetle, (Omus dejeanii) | omus dejeanii | - | 6 | SC |
| ground beetle, (Pterostichus johnsoni) | pterostichus johnsoni | - | 6 | SC |
| Ground beetle, Arbuckle Cave | Horologion speokoites | - | 5 | SC |
| Ground beetle, Beller's | Agonum belleri | - | 1 | SC |
| Ground beetle, gracile anchotefflus | Anchotefflus gracilis | - | 1 | SC |
| Ground beetle, Haleakala deropristus | Deropristus deroderus | - | 1 | SC |
| Ground beetle, Haleakala pseudobroscus | Pseudobroscus lentus | - | 1 | SC |
| Ground beetle, heavy metromenus | Metromenus bardus | - | 1 | SC |
| Ground beetle, Humboldt | Scaphinotus longiceps | - | 1 | SC |
| Ground beetle, Kauai disenochus | Disenochus micantipennis | - | 1 | SC |
| Ground beetle, Oahu blackburnia | Blackburnia insignis | - | 1 | SC |
| Ground beetle, oceanic metromenus | Metromenus oceanicus | - | 1 | SC |
| Ground beetle, Roth's blind | Pterostichus rothi | - | 2 | SC |
| Ground beetle, Schaum's Blue Ridge | Sphaeroderus schaumi ssp. | - | 5 | SC |
| Ground beetle, Siskiyou | Nebria gebleri siskiyouensis | - | 1 | SC |
| Ground beetle, South Forks | Nebria darlingtoni | - | 1 | SC |
| Ground beetle, transient atelothrus | Atelothrus transiens | - | 1 | SC |
| Ground beetle, Trinity Alps | Nebria sahlbergii triad | - | 1 | SC |
| Ground beetle, wedge-winged metromenus | Metromenus cuneipennis | - | 1 | SC |
| Ground beetle, [unnamed] | Rhadine exilis | - | 2 | E |
| Ground beetle, [unnamed] | Rhadine infernalis | - | 2 | E |
| Ground beetle, [unnamed] | Rhadine ozarkensis | - | 4 | SC |
| Ground beetle, [unnamed] | Scaphinotus behrensi | - | 1 | SC |
| Ground beetle, [unnamed] | Scaphinotus inflectus | - | 4 | SC |
| Ground beetle, [unnamed] | Scaphinotus parisiana | - | 4 | SC |
| Ground squirrel, Richardson's | Spermophilus richardsoni nevadensis | - | 1 | RT |
| Ground squirrel, White Mountains | Spermophilus tridecemlineatus monticola | - | 2 | RT |
| Ground-Dove, Friendly | Gallicolumba stairi | American Samoa DPS | 1 | C |
| Ground-dove, Guam white-throated | Gallicolumba xanthonura xanthonura | - | 1 | RT |
| Ground-plum, Guthrie's (=Pyne's) | Astragalus bibullatus | - | 4 | E |
| Groundsel Beaver Mountain | Packera castoreus | - | 6 | SC |
| Groundsel Podunk | Packera malmstenii | - | 6 | SC |
| Groundsel, Huachuca | Senecio huachucanus | - | 2 | SC |
| Groundsel, intermediate | Senecio dimorphophyllus intermedius | - | 6 | RT |
| Groundsel, Porter's | Senecio porteri | - | 1 | RT |
| Groundsel, San Francisco Peaks | Senecio franciscanus | - | 2 | T |
| Groundsel, Spellenberg's | Senecio spellenbergii | - | 2 | SC |
| Groundsel, [unnamed] | Senecio hallii discoidea | - | 6 | RT |
| Grouse, Columbian sharp-tailed | Tympanuchus phasianellus columbianus | - | 1 | RT |
| Guaco | Mikania stevensiana | - | 4 | RT |
| Guajon | Eleutherodactylus cooki | - | 4 | T |
| Guan, Cauca | Penelope perspicax | - | Foreign | PE |
| Guan, horned | Oreophasis derbianus | - | Foreign | E |
| Guan, white-winged | Penelope albipennis | - | Foreign | E |
| Guineafowl, white-breasted | Agelastes meleagrides | - | Foreign | T |
| Gull, Audouin's | Larus audouinii | - | Foreign | E |
| gull, Laughing | larus atricilla | - | 1 | SC |
| Gull, relict | Larus relictus | - | Foreign | E |
| Gum, bear | Nyssa ursina | - | 4 | SC |
| Gumplant, Ash Meadows | Grindelia fraxino-pratensis | - | 8 | T |
| Gumplant, Cuyamaca | Grindelia hallii | - | 1 | RT |
| Gumplant, Howell's | Grindelia howellii | - | 1 | SC |
| Gumplant, Humboldt Bay | Grindelia stricta blakei | - | 1 | SC |
| Gumplant, San Francisco | Grindelia hirsuta maritima | - | 1 | SC |
| Gumweed, plains | Grindelia oolepis | - | 2 | RT |
| Haha | Cyanea acuminata | - | 1 | E |
| Haha | Cyanea asarifolia | - | 1 | E |
| Haha | Cyanea asplenifolia | - | 1 | C |
| Haha | Cyanea calycina | - | 1 | C |
| Haha | Cyanea copelandii ssp. copelandii | - | 1 | E |
| Haha | Cyanea copelandii ssp. haleakalaensis | - | 1 | E |
| Haha | Cyanea dolichopoda | - | 1 | E |
| Haha | Cyanea dunbarii | - | 1 | E |
| Haha | Cyanea eleeleensis | - | 1 | E |
| Haha | Cyanea glabra | - | 1 | E |
| Haha | Cyanea grimesiana ssp. grimesiana | - | 1 | E |
| Haha | Cyanea grimesiana ssp. obatae | - | 1 | E |
| Haha | Cyanea hamatiflora ssp. carlsonii | - | 1 | E |
| Haha | Cyanea hamatiflora ssp. hamatiflora | - | 1 | E |
| Haha | Cyanea humboldtiana | - | 1 | E |
| Haha | Cyanea kolekoleensis | - | 1 | E |
| Haha | Cyanea koolauensis | - | 1 | E |
| Haha | Cyanea kuhihewa | - | 1 | E |
| Haha | Cyanea kunthiana | - | 1 | C |
| Haha | Cyanea lanceolata | - | 1 | C |
| Haha | Cyanea lobata | - | 1 | E |
| Haha | Cyanea longiflora | - | 1 | E |
| Haha | Cyanea longissima | - | 1 | SC |
| Haha | Cyanea macrostegia ssp. gibsonii | - | 1 | E |
| Haha | Cyanea mannii | - | 1 | E |
| Haha | Cyanea marksii | - | 1 | SC |
| Haha | Cyanea mceldowneyi | - | 1 | E |
| Haha | Cyanea obtusa | - | 1 | C |
| Haha | Cyanea pinnatifida | - | 1 | E |
| Haha | Cyanea platyphylla | - | 1 | E |
| Haha | Cyanea procera | - | 1 | E |
| Haha | Cyanea pseudofauriei | - | 1 | RT |
| Haha | Cyanea recta | - | 1 | T |
| Haha | Cyanea remyi | - | 1 | E |
| Haha | Cyanea shipmanii | - | 1 | E |
| Haha | Cyanea st.-johnii | - | 1 | E |
| Haha | Cyanea stictophylla | - | 1 | E |
| Haha | Cyanea superba | - | 1 | E |
| Haha | Cyanea truncata | - | 1 | E |
| Haha | Cyanea undulata | - | 1 | E |
| Hairstreak, Santa Monica Mountains | Satyrium auretorum fumosum | - | 1 | RT |
| Hairstreak, Sweadner's olive | Mitoura gryneus sweadneri | - | 4 | SC |
| Hairstreak, Thorne's | Mitoura thornei | - | 8 | UR |
| Haiwale | Cyrtandra paliku | - | 1 | E |
| Hala pepe | Pleomele fernaldii | - | 1 | C |
| Hala pepe | Pleomele forbesii | - | 1 | C |
| Hala pepe | Pleomele hawaiiensis | - | 1 | E |
| Halapepe, [unnamed] | Pleomele aurea | - | 1 | RT |
| Halimolobus, virgate | Halimolobos virgata | - | 1 | RT |
| Hanging fly, Gold rush | Orbittacus obscurus | - | 1 | SC |
| Hao | Rauvolfia sandwicensis sandwicensis | - | 1 | RT |
| Haplopappus, Palmer's | Haplopappus palmeri palmeri | - | 1 | SC |
| Haplopappus, serpentine | Haplopappus ophitidis | - | 1 | RT |
| Haplopappus, Tahoe | Haplopappus eximius | - | 1 | RT |
| Hare, hispid | Caprolagus hispidus | - | Foreign | E |
| Hare, Sierra Nevada snowshoe | Lepus americanus tahoensis | - | 1 | SC |
| harebell, Chaparral | campanula exigua | - | 6 | SC |
| Harebell, Mt. Hamilton | Campanula sharsmithiae | - | 1 | SC |
| Harebell, Olympic | Campanula piperi | - | 1 | RT |
| Harebell, swamp | Campanula californica | - | 1 | SC |
| Harebell, Wilkin's | Campanula wilkinsiana | - | 1 | SC |
| Harebells, Avon Park | Crotalaria avonensis | - | 4 | E |
| Harperella | Ptilimnium nodosum | - | 5 | E |
| harrier, Northern | circus cyaneus | - | 7 | SC |
| Hartebeest, Swayne's | Alcelaphus buselaphus swaynei | - | Foreign | E |
| Hartebeest, Tora | Alcelaphus buselaphus tora | - | Foreign | E |
| Hartwrightia, [unnamed] | Hartwrightia floridana | - | 4 | SC |
| Harvestman, Anza Borrego blind | Sitalcina borregoensis | - | NA | RT |
| Harvestman, Bee Creek Cave | Texella reddelli | - | 2 | E |
| Harvestman, Bone Cave | Texella reyesi | - | 2 | E |
| Harvestman, Cokendolpher Cave | Texella cokendolpheri | - | 2 | E |
| Harvestman, Edgewood blind | Calcina minor | - | 1 | SC |
| Harvestman, Edgewood Park micro-blind | Microcina edgewoodensis | - | 1 | RT |
| Harvestman, Graham's | Banksula grahami | - | NA | SU |
| Harvestman, Hom's micro-blind | Microcina homi | - | 1 | SC |
| Harvestman, Jung's micro-blind | Microcina jungi | - | 1 | UR |
| Harvestman, Lee's micro-blind | Microcina leei | - | 1 | SC |
| Harvestman, Lum's micro-blind | Microcina lumi | - | 1 | SC |
| Harvestman, Marin blind | Calicina diminua | - | NA | SU |
| Harvestman, Melones | Banksula melones | - | NA | SU |
| harvestman, New Comanche Trail cave | texella | - | 6 | SC |
| Harvestman, Ross micro-blind | Microcina sp | - | NA | RT |
| Harvestman, Silver Creek blind | Calicina jungi | - | NA | RT |
| Harvestman, Tiburon micro-blind | Microcina tiburona | - | 1 | SC |
| Hau kuahiwi | Hibiscadelphus crucibracteatus | - | 1 | SC |
| Hau kuahiwi | Hibiscadelphus giffardianus | - | 1 | E |
| Hau kuahiwi | Hibiscadelphus hualalaiensis | - | 1 | E |
| Hau kuahiwi | Hibiscadelphus woodii | - | 1 | E |
| Haw, [unnamed] | Crataegus harbisonii | - | 4 | SC |
| hawk, Cooper's | Accipiter cooperii | - | 8 | SC |
| Hawk, ferruginous | Buteo regalis | - | 6 | RT |
| Hawk, Galapagos | Buteo galapagoensis | - | Foreign | E |
| hawk, Harris' | parabuteo unicinctus | - | 6 | SC |
| Hawk, Hawaiian (='lo) | Buteo solitarius | - | 1 | E |
| Hawk, northern gray | Buteo nitidus maximus | - | 2 | SC |
| Hawk, Puerto Rican broad-winged | Buteo platypterus brunnescens | - | 4 | E |
| Hawk, Puerto Rican sharp-shinned | Accipiter striatus venator | - | 4 | E |
| hawk, Red-shouldered | buteo lineatus | - | 6 | SC |
| hawk, Rough-legged | buteo lagopus | - | 7 | SC |
| Hawk, Sharp shinned | Accipiter striatus | - | 8 | SC |
| hawk, short-tailed | Buteo brachyurus | - | 4 | SC |
| hawk, short-tailed | Buteo brachyurus | Florida population | 4 | SU |
| Hawk, Swainson's | Buteo swainsoni | - | 3 | RT |
| hawkweed, Mogollon | hieracium fendleri | - | 2 | SC |
| Hawkweed, Pringle | Hieracium pringlei | - | 2 | SC |
| Hawkweed, [unnamed] | Hieracium robinsonii | - | 5 | SC |
| Hawthorn, barberry-leaved | Crataegus berberifolia | - | 4 | RT |
| Hawthorn, Warner | Crataegus warneri | - | 2 | SC |
| Hazardia, island | Hazardia cana | - | 1 | SC |
| Hazardia, Orcutt's | Hazardia orcuttii | - | 8 | C |
| Ha`iwale | Cyrtandra biserrata | - | 1 | SC |
| Ha`iwale | Cyrtandra crenata | - | 1 | E |
| Ha`iwale | Cyrtandra dentata | - | 1 | E |
| Ha`iwale | Cyrtandra filipes | - | 1 | C |
| Ha`iwale | Cyrtandra giffardii | - | 1 | E |
| Ha`iwale | Cyrtandra halawensis | - | 1 | SC |
| Ha`iwale | Cyrtandra hematos | - | 1 | SC |
| Ha`iwale | Cyrtandra kaulantha | - | 1 | C |
| Ha`iwale | Cyrtandra kealiae | - | 1 | SC |
| Ha`iwale | Cyrtandra limahuliensis | - | 1 | T |
| Ha`iwale | Cyrtandra lydgatei | - | 1 | SC |
| Ha`iwale | Cyrtandra macrocalyx | - | 1 | SC |
| Ha`iwale | Cyrtandra menziesii | - | 1 | RT |
| Ha`iwale | Cyrtandra munroi | - | 1 | E |
| Ha`iwale | Cyrtandra oenobarba | - | 1 | E |
| Ha`iwale | Cyrtandra oxybapha | - | 1 | C |
| Ha`iwale | Cyrtandra pickeringii | - | 1 | SC |
| Ha`iwale | Cyrtandra polyantha | - | 1 | E |
| Ha`iwale | Cyrtandra pruinosa | - | 1 | SC |
| Ha`iwale | Cyrtandra sandwicensis | - | 1 | SC |
| Ha`iwale | Cyrtandra sessilis | - | 1 | C |
| Ha`iwale | Cyrtandra subumbellata | - | 1 | E |
| Ha`iwale | Cyrtandra tintinnabula | - | 1 | E |
| Ha`iwale | Cyrtandra viridiflora | - | 1 | E |
| Heartleaf, dwarf-flowered | Hexastylis naniflora | - | 4 | T |
| Heartleaf, French Broad | Hexastylis rhombiformis | - | 4 | SC |
| Heartleaf, Harper's | Hexastylis speciosa | - | 4 | RT |
| Heartleaf, [unnamed] | Hexastylis lewisii | - | 4 | RT |
| Heartscale | Atriplex cordulata | - | 1 | SC |
| Heather, mountain golden | Hudsonia montana | - | 4 | T |
| Heau | Exocarpos luteolus | - | 1 | E |
| Hedge-hyssop, Boggs Lake | Gratiola heterosepala | - | 1 | RT |
| Hedge-nettle, Tallahassee | Stachys hyssopifolia lythroides | - | 4 | SC |
| Hedgehog cactus, Fitch's | Echinocereus reichenbachii fitchii | - | 2 | RT |
| Hedgehog cactus, golden-spined | Echinocereus chloranthus neocapillus | - | 2 | SC |
| Hedgehog cactus, Howe's | Echinocereus engelmannii howei | - | 1 | SC |
| Hedgehog cactus, Munz's | Echinocereus engelmannii munzii | - | 1 | SC |
| Hedgehog cactus, purple-spined | Echinocereus engelmannii var. purpureus | - | 6 | DO |
| Hedgehog cactus, rusty | Echinocereus russanthus | - | 2 | RT |
| Hedyotis, Na Pali beach | Hedyotis st.-johnii | - | 1 | E |
| Hedyotis, narrow-leaved | Hedyotis angusta umbrosa | - | 1 | RT |
| Heelsplitter, Alabama (=inflated) | Potamilus inflatus | - | 4 | T |
| Heelsplitter, Barrens | Lasmigona sp. | - | 4 | SC |
| Heelsplitter, Carolina | Lasmigona decorata | - | 4 | E |
| Heelsplitter, Tennessee | Lasmigona holstonia | - | 4 | SC |
| Heelsplitter, Texas | Potamilus amphichaenus | - | 2 | UR |
| Hellbender | Cryptobranchus alleganiensis | - | 3 | RT |
| Hellbender, Eastern | Cryptobranchus alleganiensis alleganiensis | - | 3 | SC |
| Hellbender, Ozark | Cryptobranchus alleganiensis bishopi | - | 3 | C |
| Hellebore, false | Veratrum woodii | - | 4 | RT |
| Hermit, hook-billed (hummingbird) | Ramphodon (=Glaucis) dohrnii | - | Foreign | E |
| Hermit, Margaretta's | Phaethornis malaris margarettae | - | Foreign | PE |
| heron, Black-crowned night | nycticorax nycticorax | - | 6 | SC |
| heron, Great blue | ardae herodias | - | 7 | SC |
| hesperian, Big Bar | Vespericola pressleyi | - | 8 | SU |
| Hesperian, Karok | Vespericola karokorum | - | 1 | RT |
| hesperian, Shasta | Vespericola shasta | - | 8 | SU |
| Hexalectris, Greenman's | Hexalectris grandiflora | - | 2 | RT |
| Hibiscus, California | Hibiscus californicus | - | 1 | RT |
| Hibiscus, Clay's | Hibiscus clayi | - | 1 | E |
| Hicaquillo | Dendropemon sintenisii | - | 4 | SC |
| Hickorynut, southern | Obovaria jacksoniana | - | 2 | RT |
| Higgins eye (pearlymussel) | Lampsilis higginsii | - | 3 | E |
| Higuero de sierra | Crescentia portoricensis | - | 4 | E |
| Hoary-pea, pineland | Tephrosia mohrii | - | 4 | SC |
| Hog, pygmy | Sus salvanius | - | Foreign | E |
| hoita, Loma Prieta | hoita strobilina | - | 8 | SC |
| Hoja menuda | Psidium sintenisii | - | 4 | SC |
| Holei | Ochrosia haleakalae | - | 1 | C |
| Holei | Ochrosia kilaueaensis | - | 1 | E |
| Hollisteria | Hollisteria lanata | - | 1 | SC |
| Holly, Cook's | Ilex cookii | - | 4 | E |
| Holly, long-stalked | Ilex collina | - | 5 | RT |
| Holly, [unnamed] | Ilex amelanchier | - | 4 | RT |
| Honey-eater, cardinal | Myzomela cardinalis saffordi | - | 1 | RT |
| Honeycreeper, crested | Palmeria dolei | - | 1 | E |
| Honeyeater, helmeted | Lichenostomus melanops cassidix (=Meliphaga c.) | - | Foreign | E |
| Honohono | Haplostachys haplostachya | - | 1 | E |
| Hop hornbeam, Big Bend | Ostrya chisosensis | - | 2 | SC |
| Horkelia, Barton Flats | Horkelia wilderae | - | 1 | SC |
| Horkelia, Bolander's | Horkelia bolanderi | - | 1 | SC |
| Horkelia, Henderson's | Horkelia hendersonii | - | 1 | UR |
| Horkelia, Parry's | Horkelia parryi | - | 1 | SC |
| Horkelia, Point Reyes | Horkelia marinensis | - | 1 | SC |
| horkelia, shaggy | Horkelia congesta ssp. congesta | - | 1 | SC |
| Horkelia, Tulare | Horkelia tularensis | - | 1 | SC |
| Horkelia, wedge-leaved | Horkelia cuneata sericea | - | 1 | SC |
| Hornbill, helmeted | Buceros (=Rhinoplax) vigil | - | Foreign | E |
| Horned lark, streaked | Eremophila alpestris strigata | - | 1 | C |
| Hornshell, Texas | Popenaias popei | - | 2 | C |
| Hornsnail, broken | Pleurocera postelli | - | 4 | SC |
| Hornsnail, corpulent | Pleurocera corpulenta | - | 4 | SC |
| Hornsnail, ringed | Pleurocera annulifera | - | 4 | SC |
| Hornsnail, rough | Pleurocera foremani | - | 4 | PE |
| Hornsnail, rugged | Pleurocera alveare | - | 4 | SC |
| Hornsnail, shortspire | Pleurocera curta | - | 4 | SC |
| Hornsnail, skirted | Pleurocera pyrenella | - | 4 | SC |
| Hornsnail, spiral | Pleurocera brumbyi | - | 4 | SC |
| Hornsnail, telescope | Pleurocera walkeri | - | 4 | SC |
| Hornsnail, upland | Pleurocera showalteri | - | 4 | SC |
| Hornsnail, [unnamed] | Pleurocera viridulum | - | 4 | SC |
| Hornwort, Florida | Ceratophyllum floridanum | - | 4 | RT |
| Horse, Przewalski's | Equus przewalskii | - | Foreign | E |
| Horse-mint, [unnamed] | Monarda fistulosa brevis | - | 5 | SC |
| Horse-mint, [unnamed] | Monarda stipitatoglandulosa | - | 4 | RT |
| Horse-nettle, [unnamed] | Solanum carolinense hirsutum | - | 4 | SC |
| Hosackia, prostrate | Lotus nuttallianus | - | 1 | SC |
| Hosackia, silver, San Clemente Island | Lotus argophyllus adsurgens | - | 1 | SC |
| Hosackia, silver, Santa Cruz Island | Lotus argophyllus niveus | - | 1 | SC |
| Howellia, water | Howellia aquatilis | - | 6 | T |
| Ho`awa | Pittosporum napaliense | - | 1 | E |
| Huaco, Runyon | Manfreda longiflora | - | 2 | SC |
| Huckleberry, box | Gaylussacia brachycera | - | 5 | RT |
| Huckleberry, Raynor's | Vaccinium sempervirens | - | 4 | SC |
| Huemul, north Andean | Hippocamelus antisensis | - | Foreign | E |
| Huemul, south Andean | Hippocamelus bisulcus | - | Foreign | E |
| Hulsea, Beautiful | Hulsea vestita ssp. callicarpha | - | 8 | SC |
| Hulsea, Inyo | Hulsea vestita inyoensis | - | 1 | RT |
| Hulumoa | Korthalsella degeneri | - | 1 | C |
| hummingbird, Honduran emerald | Amazilia luciae | - | 9 | UR |
| hummingbird, Rufous | selasphorus rufus | - | 6 | SC |
| Hutia, Cabrera's | Capromys angelcabrerai | - | Foreign | E |
| Hutia, dwarf | Capromys nana | - | Foreign | E |
| Hutia, large-eared | Capromys auritus | - | Foreign | E |
| Hutia, little earth | Capromys sanfelipensis | - | Foreign | E |
| Hydrobe, Blue Spring | Aphaostracon asthenes | - | 4 | SC |
| Hydrobe, dense | Aphaostracon pycnus | - | 4 | SC |
| Hydrobe, Fenney Spring | Aphaostracon xynoelictus | - | 4 | SC |
| Hydrobe, Wekiwa | Aphaostracon monas | - | 4 | SC |
| Hydroid, [unnamed] | Ostroumovia horii | - | 1 | SC |
| Hyena, Barbary | Hyaena hyaena barbara | - | Foreign | E |
| Hyena, brown | Parahyaena (=Hyaena) brunnea | - | Foreign | E |
| Hymenopappus, cobweb | Hymenopappus filifolius tomentosus | - | 6 | RT |
| Hypericum, highlands scrub | Hypericum cumulicola | - | 4 | E |
| Iagu, Hayun (=(Guam), Tronkon guafi (Rota)) | Serianthes nelsonii | - | 1 | E |
| Ibex, Pyrenean | Capra pyrenaica pyrenaica | - | Foreign | E |
| Ibex, Walia | Capra walie | - | Foreign | E |
| Ibis, giant | Pseudibis gigantea | - | NA | E |
| Ibis, Japanese crested | Nipponia nippon | - | Foreign | E |
| Ibis, northern bald | Geronticus eremita | - | Foreign | E |
| Ibis, white-faced | Plegadis chihi | - | 1 | SC |
| Ice grass | Phippsia algida | - | 6 | RT |
| Iguana, Acklins ground | Cyclura rileyi nuchalis | - | Foreign | T |
| Iguana, Allen's Cay | Cyclura cychlura inornata | - | Foreign | T |
| Iguana, Andros Island ground | Cyclura cychlura cychlura | - | Foreign | T |
| Iguana, Anegada ground | Cyclura pinguis | - | Foreign | E |
| Iguana, Barrington land | Conolophus pallidus | - | Foreign | E |
| Iguana, Cayman Brac ground | Cyclura nubila caymanensis | - | Foreign | T |
| Iguana, Cuban ground | Cyclura nubila nubila | - | Foreign | T |
| iguana, Desert | dipsosaurus dorsalis | - | 2 | SC |
| Iguana, Exuma Island | Cyclura cychlura figginsi | - | Foreign | T |
| Iguana, Fiji banded | Brachylophus fasciatus | - | Foreign | E |
| Iguana, Fiji crested | Brachylophus vitiensis | - | Foreign | E |
| Iguana, Grand Cayman ground | Cyclura nubila lewisi | - | Foreign | E |
| Iguana, Jamaican | Cyclura collei | - | Foreign | E |
| Iguana, Mayaguana | Cyclura carinata bartschi | - | Foreign | T |
| Iguana, Mona ground | Cyclura cornuta stejnegeri | - | 4 | T |
| Iguana, Navassa Island | Cyclura cornuta nigerrima | - | 4 | RT |
| Iguana, Turks and Caicos | Cyclura carinata carinata | - | Foreign | T |
| Iguana, Watling Island ground | Cyclura rileyi rileyi | - | Foreign | E |
| Iguana, White Cay ground | Cyclura rileyi cristata | - | Foreign | T |
| Ihi`ihi | Marsilea villosa | - | 1 | E |
| Iliau, dwarf | Wilkesia hobdyi | - | 1 | E |
| Impala, black-faced | Aepyceros melampus petersi | - | Foreign | E |
| Indian paintbrush, Jeff Davis Parish | Castilleja ludoviciana | - | 4 | RT |
| Indian paintbrush, Reveal | Castilleja revealii | - | 6 | SC |
| Indian paintbrush, San Clemente Island | Castilleja grisea | - | 8 | E |
| Indian paintbrush, Tushar | Castilleja parvula | - | 6 | SC |
| Indian paintbrush, [unnamed] | Castilleja ciliata | - | 2 | SC |
| Indian paintbrush, [unnamed] | Castilleja scabrida | - | 6 | RT |
| Indigo bush, Mojave | Psorothamnus arborescens arborescens | - | 1 | RT |
| Indigo, Florida | Indigofera mucronata keyensis | - | 4 | RT |
| Indigobush, Gentry's | Dalea tentaculoides | - | 2 | RT |
| Indri | Indri indri (entire genus) | - | Foreign | E |
| Inside-out flower, Siskiyou | Vancouveria chrysantha | - | 1 | RT |
| Ipomopsis, Holy Ghost | Ipomopsis sancti-spiritus | - | 2 | E |
| Iris, Clackamas | Iris tenuis | - | 1 | RT |
| Iris, dwarf lake | Iris lacustris | - | 3 | T |
| Iris, Klamath | Iris tenax klamathensis | - | 1 | RT |
| Iris, [unnamed] | Iris pariensis | - | 6 | SC |
| Iris, [unnamed] | Iris tenax gormanii | - | 1 | RT |
| Irisette, white | Sisyrinchium dichotomum | - | 4 | E |
| Ironwood, Catalina | Lyonothamnus floribundus floribundus | - | 1 | SC |
| Ironwood, fern-leaved | Lyonothamnus floribundus asplenifolius | - | 1 | SC |
| Ischaemum, Hilo | Ischaemum byrone | - | 1 | E |
| Islandsnail, California McCoy snail | Micrarionta rowelli mccoiana | - | 1 | SC |
| Islandsnail, pricklypear | Micrarionta opuntia | - | 1 | SC |
| Islandsnail, San Clemente | Micrarionta gabbi | - | 1 | SC |
| Islandsnail, San Nicolas | Micrarionta feralis | - | 1 | SC |
| Islandsnail, Santa Barbara | Micrarionta facta | - | 1 | SC |
| Islandsnail, [unnamed] | Micrarionta rowelli bakerensis | - | 1 | SC |
| isopod, (Caecidotea reddelli) | caecidotea reddelli | - | 6 | SC |
| isopod, (Miktoniscus) | miktoniscus | - | 6 | SC |
| isopod, (Trichoniscidae) | trichoniscoides | - | 6 | SC |
| Isopod, Bat Cave | Caecidotea macropoda | - | 2 | SC |
| Isopod, Clifton Cave | Caecidotea barri | - | 4 | SC |
| Isopod, Franz's | Caecidotea franzi | - | 5 | SC |
| Isopod, Lee County cave | Lirceus usdagalun | - | 5 | E |
| Isopod, Madison Cave | Antrolana lira | - | 5 | T |
| Isopod, Nickajack Cave | Caecidotea nickajackensis | - | 4 | SC |
| Isopod, Rye Cove Cave | Lirceus culveri | - | 5 | SC |
| Isopod, Socorro | Thermosphaeroma thermophilus | - | 2 | E |
| Isopod, unnamed | Caecidotea acuticarpa | - | NA | SU |
| Isopod, [unnamed] | Caecidotea cannulus | - | 5 | SC |
| Isopod, [unnamed] | Caecidotea filicispeluncae | - | 3 | SC |
| Isopod, [unnamed] | Caecidotea simonini | - | 5 | SC |
| Isopod, [unnamed] | Caecidotea sinuncus | - | 5 | SC |
| Isopod, [unnamed] | Caecidotea tomalensis | - | 1 | SC |
| Ivesia, Ash Creek | Ivesia paniculata | - | 1 | SC |
| Ivesia, Ash Meadows | Ivesia kingii var. eremica | - | 8 | T |
| Ivesia, Dog Valley | Ivesia aperta canina | - | 1 | SC |
| Ivesia, grimy | Ivesia rhypara rhypara | - | 1 | RT |
| Ivesia, Pickering | Ivesia pickeringii | - | 1 | SC |
| Ivesia, Pine Nut Mountains | Ivesia pityocharis | - | 1 | SC |
| Ivesia, Plumas | Ivesia sericleuca | - | 1 | SC |
| Ivesia, Sierra Valley | Ivesia aperta aperta | - | 1 | SC |
| Ivesia, silver-haired | Ivesia argyrocoma | - | 1 | SC |
| Ivesia, Tahquitz | Ivesia callida | - | 1 | SC |
| Ivesia, Venator Canyon, Shelly's | Ivesia rhypara shellyi | - | 1 | SC |
| Ivesia, Webber | Ivesia webberi | - | 8 | C |
| Ixia, Bartram's | Salpingostylis coelestinum | - | 4 | RT |
| Ixia, fall-flowering | Nemastylis floridana | - | 4 | SC |
| Jack-bean, [unnamed] | Canavalia iaoensis | - | 1 | RT |
| Jack-bean, [unnamed] | Canavalia kauaiensis | - | 1 | RT |
| Jack-bean, [unnamed] | Canavalia kauensis | - | 1 | RT |
| Jack-bean, [unnamed] | Canavalia sanguinea | - | 1 | RT |
| Jackrabbit, San Diego black-tailed | Lepus californicus bennettii | - | 1 | SC |
| Jackrabbit, white-sided | Lepus callotis | - | 2 | UR |
| Jacob's ladder, Hinckley's | Polemonium pauciflorum hinckleyi | - | 2 | SC |
| Jacob's ladder, [unnamed] | Polemonium occidentale lacustre | - | 3 | SC |
| Jacob's ladder, [unnamed] | Polemonium reptans villosum | - | 4 | RT |
| Jacob's ladder, [unnamed] | Polemonium vanbruntiae | - | 5 | RT |
| Jacquemontia, beach | Jacquemontia reclinata | - | 4 | E |
| Jacquemontia, pineland | Jacquemontia curtissii | - | 4 | SC |
| Jaguar | Panthera onca | - | 2 | E |
| Jaguarundi, Guatemalan | Herpailurus (=Felis) yagouaroundi fossata | - | Foreign | E |
| Jaguarundi, Gulf Coast | Herpailurus (=Felis) yagouaroundi cacomitli | - | 2 | E |
| Jaguarundi, Panamanian | Herpailurus (=Felis) yagouaroundi panamensis | - | Foreign | E |
| Jaguarundi, Sinaloan | Herpailurus (=Felis) yagouaroundi tolteca | - | 2 | E |
| Jamesianthus, Alabama | Jamesianthus alabamensis | - | 4 | SC |
| Jatropha, Costa Rican | Jatropha costaricensis | - | Foreign | E |
| Jay, Eagle Mountain scrub | Aphelocoma coerulescens cana | - | 1 | SC |
| Jepsonia, island | Jepsonia malvifolia | - | 1 | SC |
| Jerusalem cricket, Coachella Valley | Stenopelmatus cahuilaensis | - | 1 | SC |
| Jerusalem cricket, Colton Sand Dune | Stenopelmatus spp | - | NA | RT |
| Jerusalem cricket, Kelso | Ammopelmatus kelsoensis | - | 1 | SC |
| Jerusalem cricket, Navajo | Stenopelmatus navajo | - | 2 | SC |
| Jerusalem cricket, Point Conception | Ammopelmatus muwu | - | 1 | SC |
| Jewel beetle, Algodones croton | Agrilus harenus | entire | 8 | RT |
| Jewel beetle, Algodones white wax | Prasinalia imperialis | entire | 8 | RT |
| Jewel beetle, Algondones sand | Lepismadora algodones | entire | 8 | RT |
| Jewelflower, Auburua Ranch | Streptanthus insignis lyonii | - | 1 | SC |
| Jewelflower, California | Caulanthus californicus | - | 8 | E |
| Jewelflower, Dorr's Cabin | Streptanthus morrisonii hirtiflorus | - | 1 | SC |
| Jewelflower, Evalyn's | Streptanthus farnsworthianus | - | 1 | RT |
| Jewelflower, few-flowered | Streptanthus sparsiflorus | - | 2 | SC |
| Jewelflower, Freed's | Streptanthus brachiatus hoffmanii | - | 1 | SC |
| Jewelflower, Howell's | Streptanthus howellii | - | 1 | RT |
| Jewelflower, Kruckeberg's | Streptanthus morrisonii kruckebergii | - | 1 | SC |
| Jewelflower, Laguna Mountains | Streptanthus bernardinus | - | 1 | RT |
| Jewelflower, Lemmon's | Streptanthus lemmonii | - | 2 | SC |
| Jewelflower, Masonic Mountain | Streptanthus oliganthus | - | 1 | SC |
| Jewelflower, Metcalf Canyon | Streptanthus albidus ssp. albidus | - | 8 | E |
| Jewelflower, Morrison's | Streptanthus morrisonii morrisonii | - | 1 | SC |
| Jewelflower, most beautiful | Streptanthus albidus peramoenus | - | 1 | SC |
| Jewelflower, Mount Tamalpais | Streptanthus glandulosus pulchellus | - | 1 | RT |
| Jewelflower, Mt. Diablo | Streptanthus hispidus | - | 1 | SC |
| Jewelflower, Mt. Hamilton | Streptanthus callistus | - | 1 | SC |
| Jewelflower, Payson's | Caulanthus simulans | - | 1 | SC |
| Jewelflower, Piute Mountains | Streptanthus cordatus piutensis | - | 1 | SC |
| Jewelflower, Santa Barbara | Caulanthus amplexicaulis barbarae | - | 1 | RT |
| Jewelflower, secund | Streptanthus glandulosus hoffmanii | - | 1 | SC |
| Jewelflower, slender-pod | Caulanthus stenocarpus | - | 1 | RT |
| Jewelflower, sp. nov. ined. (Pit River) | Streptanthus sp. | - | 1 | SC |
| Jewelflower, Tamalpais | Streptanthus batrachopus | - | 1 | SC |
| Jewelflower, Tehipite Valley | Streptanthus fenestratus | - | 1 | RT |
| Jewelflower, Three Peaks | Streptanthus morrisonii elatus | - | 1 | SC |
| Jewelflower, Tiburon | Streptanthus niger | - | 8 | E |
| Jewelflower, [unnamed] | Streptanthus squamiformis | - | 2 | SC |
| Jicotea | Pseudemys stejnegeri | - | 4 | SC |
| Joint-vetch, sensitive | Aeschynomene virginica | - | 5 | T |
| Jointweed, large-leaved | Polygonella macrophylla | - | 4 | SC |
| Jointweed, Parks' | Polygonella parksii | - | 2 | RT |
| Juga, Basalt | Juga sp | - | 1 | SU |
| Juga, cinnamon | Juga spb | - | 8 | SU |
| jumping-slug, Burrington | Hemphillia burringtoni | - | 1 | SU |
| June beetle, Atascodero | Polyphylla nubila | - | 1 | SC |
| June Beetle, Caseys | Dinacoma caseyi | - | 8 | PE |
| June beetle, Death Valley | Polyphylla erratica | - | 1 | SC |
| June beetle, Delta | Polyphylla stellata | - | 1 | SC |
| June beetle, Saline Valley snow-front | Polyphylla anteronivea | - | 1 | SC |
| June beetle, Spotted Warner Valley Dunes | Polyphylla avittata | - | 6 | SC |
| Kagu | Rhynochetos jubatus | - | Foreign | E |
| Kakapo | Strigops habroptilus | - | Foreign | E |
| Kamakahala | Labordia cyrtandrae | - | 1 | E |
| Kamakahala | Labordia fagraeoidea fagraeoidea | - | 1 | RT |
| Kamakahala | Labordia helleri | - | 1 | E |
| Kamakahala | Labordia lydgatei | - | 1 | E |
| Kamakahala | Labordia membranacea | - | 1 | RT |
| Kamakahala | Labordia pumila | - | 1 | E |
| Kamakahala | Labordia tinifolia var. lanaiensis | - | 1 | E |
| Kamakahala | Labordia tinifolia var. wahiawaensis | - | 1 | E |
| Kamakahala | Labordia triflora | - | 1 | E |
| Kamanomano | Cenchrus agrimonioides | - | 1 | E |
| Kampua`a | Hedyotis fluviatilis | - | 1 | C |
| Kangaroo rat, Berkeley | Dipodomys heermanni berkleyensis | - | 8 | SC |
| Kangaroo rat, big-eared | Dipodomys elephantinus | - | 1 | RT |
| Kangaroo rat, Dolphin Island | Dipodomys microps russeolus | - | 6 | SC |
| Kangaroo rat, Dolphin Island ord's | Dipodomys ordii cineraceus | - | 6 | SC |
| kangaroo rat, Dulzura | dipodomys simulans | - | 6 | SC |
| Kangaroo rat, Earthquake Merriam's | Dipodomys merriami collinus | - | 1 | SC |
| Kangaroo rat, Fresno | Dipodomys nitratoides exilis | - | 8 | E |
| Kangaroo rat, giant | Dipodomys ingens | - | 8 | E |
| Kangaroo rat, Gunnison Island | Dipodomys microps alfredi | - | 6 | SC |
| Kangaroo rat, Marble Canyon | Dipodomys microps leucotis | - | 2 | SC |
| Kangaroo rat, Marysville California | Dipodomys californicus eximius | - | 1 | SC |
| Kangaroo rat, Merced | Dipodomys heermanni dixoni | - | 1 | SC |
| Kangaroo rat, Morro Bay | Dipodomys heermanni morroensis | - | 8 | E |
| Kangaroo rat, San Bernardino Merriam's | Dipodomys merriami parvus | - | 8 | E |
| Kangaroo rat, short-nosed | Dipodomys nitratoides brevinasus | - | 1 | SC |
| Kangaroo rat, Stephens' | Dipodomys stephensi (incl. D. cascus) | - | 8 | E |
| Kangaroo rat, Texas | Dipodomys elator | - | 2 | SC |
| Kangaroo rat, Tipton | Dipodomys nitratoides nitratoides | - | 8 | E |
| Kangaroo rat, Virgin Merriam's | Dipodomys merriami frenatus | - | 6 | SC |
| Kangaroo, eastern gray | Macropus giganteus | - | Foreign | DM |
| Kangaroo, red | Macropus rufus | - | Foreign | DM |
| Kangaroo, Tasmanian forester | Macropus giganteus tasmaniensis | - | Foreign | E |
| Kangaroo, western gray | Macropus fuliginosus | - | Foreign | DM |
| Katydid, Antioch Dunes shieldback | Neduba extincta | - | 1 | RT |
| Katydid, Big Pine Key conehead | Belocephalus micanopy | - | 4 | SC |
| Katydid, Jacalitos shield-backed | Ateloplus joaquin | - | NA | RT |
| Katydid, Keys shortwinged conehead | Belocephalus sleighti | - | 4 | SC |
| Katydid, Middlekauf's shieldback | Idiostatus middlekaufi | - | 1 | SC |
| Katydid, Nihoa banza conehead | Banza nihoa | - | 1 | SC |
| Katydid, Pinnacles shield-back | Idiostatus kathleenae | - | 1 | SC |
| Katydid, remote conehead | Conocephaloides remotus | - | 1 | RT |
| Katydid, Santa Monica shieldback | Neduba longipennis | - | 1 | SC |
| Katydid, splendid shield-backed | Ateloplus splendidus | - | NA | RT |
| Kauai hau kuahiwi | Hibiscadelphus distans | - | 1 | E |
| Kauila | Alphitonia ponderosa | - | 1 | RT |
| Kauila | Colubrina oppositifolia | - | 1 | E |
| Kaulu | Pteralyxia caumiana | - | 1 | RT |
| Kaulu | Pteralyxia kauaiensis | - | 1 | E |
| Kaulu | Pteralyxia macrocarpa | - | 1 | C |
| Kawa`u | Zanthoxylum dipetalum dipetalum | - | 1 | RT |
| Kestrel, Mauritius | Falco punctatus | - | Foreign | E |
| Kestrel, Seychelles | Falco araea | - | Foreign | E |
| Kestrel, southeastern American | Falco sparverius paulus | - | 4 | SC |
| Kidneyshell, fluted | Ptychobranchus subtentum | - | 4 | C |
| Kidneyshell, Ouachita | Ptychobranchus occidentalis | - | 6 | SC |
| Kidneyshell, southern | Ptychobranchus jonesi | - | 4 | C |
| Kidneyshell, triangular | Ptychobranchus greenii | - | 4 | E |
| Killifish, Waccamaw | Fundulus waccamensis | - | 4 | SC |
| Kingfisher, Guam Micronesian | Halcyon cinnamomina cinnamomina | - | 1 | E |
| Kio`ele | Hedyotis coriacea | - | 1 | E |
| Kiponapona | Phyllostegia racemosa | - | 1 | E |
| Kite, American swallow-tailed | Elanoides forficatus forficatus | - | 3 | RT |
| Kite, Cuba hook-billed | Chondrohierax uncinatus wilsonii | - | Foreign | E |
| Kite, Everglade snail | Rostrhamus sociabilis plumbeus | U.S.A. (FL) | 4 | E |
| Kite, Grenada hook-billed | Chondrohierax uncinatus mirus | - | Foreign | E |
| Kite, Swallow-tailed | Elanoides forficatus | - | 4 | SC |
| kite, White-tailed | elanus caeruleus | - | 6 | SC |
| Kite, White-tailed | Elanus leucurus | - | 1 | SC |
| Kittentails, [unnamed] | Synthyris ranunculina | - | 1 | SC |
| Kittiwake, red-legged | Rissa brevirostris | - | 7 | SC |
| Kiyi | Coregonus kiyi | - | 3 | SC |
| Knot, red | Calidris canutus rufa | - | 5 | C |
| Knot, red | Calidris canutus ssp. roselaari | - | 5 | SU |
| Knotweed, Bidwell's | Polygonum bidwelliae | - | 1 | RT |
| Knotweed, Marin | Polygonum marinense | - | 1 | SC |
| Knotweed, Monterey | Polygonum montereyense | - | 1 | RT |
| Knotweed, Needles | Polygonum fusiforme | - | 2 | RT |
| Knotweed, [unnamed] | Polygonum texense | - | 2 | RT |
| Koai`e | Acacia koaia | - | 1 | SC |
| Koala | Phascolarctos cinereus | - | Foreign | T |
| Kohe malama malama o kanaloa | Kanaloa kahoolawensis | - | 1 | E |
| Kokako (wattlebird) | Callaeas cinerea | - | Foreign | E |
| Koke`e, giant | Cyanea leptostegia | - | 1 | SC |
| Koki`o | Kokia drynarioides | - | 1 | E |
| Koki`o | Kokia kauaiensis | - | 1 | E |
| Koki`o | Kokia lanceolata | - | 1 | RT |
| Koki`o ke`oke`o | Hibiscus arnottianus ssp. immaculatus | - | 1 | E |
| Koki`o ke`oke`o | Hibiscus waimeae ssp. hannerae | - | 1 | E |
| Koki`o, Cooke's | Kokia cookei | - | 1 | E |
| Kolea | Myrsine fernseei | - | 1 | RT |
| Kolea | Myrsine fosbergii | - | 1 | C |
| Kolea | Myrsine juddii | - | 1 | E |
| Kolea | Myrsine knudsenii | - | 1 | E |
| Kolea | Myrsine lanaiensis oahuensis | - | 1 | RT |
| Kolea | Myrsine linearifolia | - | 1 | T |
| Kolea | Myrsine mezii | - | 1 | E |
| Kolea | Myrsine petiolata | - | 1 | RT |
| Kolea | Myrsine st-johnii | - | 1 | RT |
| Kolea | Myrsine vaccinioides | - | 1 | C |
| Kopa | Hedyotis schlechtendahliana var. remyi | - | 1 | E |
| Kopiko | Psychotria grandiflora | - | 1 | E |
| Kopiko | Psychotria hobdyi | - | 1 | E |
| Kouprey | Bos sauveli | - | Foreign | E |
| Ko`oko`olau | Bidens amplectens | - | 1 | C |
| Ko`oko`olau | Bidens campylotheca pentamera | - | 1 | C |
| Ko`oko`olau | Bidens campylotheca waihoiensis | - | 1 | C |
| Ko`oko`olau | Bidens cervicata | - | 1 | RT |
| Ko`oko`olau | Bidens conjuncta | - | 1 | C |
| Ko`oko`olau | Bidens degeneri | - | 1 | RT |
| Ko`oko`olau | Bidens hawaiensis | - | 1 | RT |
| Ko`oko`olau | Bidens macrocarpa ovatifolia | - | 1 | RT |
| Ko`oko`olau | Bidens magnidisca | - | 1 | RT |
| Ko`oko`olau | Bidens mauiensis | - | 1 | RT |
| Ko`oko`olau | Bidens menziesii leptodonta | - | 1 | RT |
| Ko`oko`olau | Bidens micrantha caduca | - | 1 | RT |
| Ko`oko`olau | Bidens micrantha ctenophylla | - | 1 | C |
| Ko`oko`olau | Bidens micrantha kaalana | - | 1 | RT |
| Ko`oko`olau | Bidens micrantha laciniata | - | 1 | RT |
| Ko`oko`olau | Bidens micrantha ssp. kalealaha | - | 1 | E |
| Ko`oko`olau | Bidens molokaiensis | - | 1 | RT |
| Ko`oko`olau | Bidens obtusiloba | - | 1 | RT |
| Ko`oko`olau | Bidens pulchella | - | 1 | RT |
| Ko`oko`olau | Bidens sandvicensis confusa | - | 1 | SC |
| Ko`oko`olau | Bidens sandwicensis setosa | - | 1 | RT |
| Ko`oko`olau | Bidens waimeana | - | 1 | RT |
| Ko`oko`olau | Bidens wiebkei | - | 1 | E |
| Ko`oloa`ula | Abutilon menziesii | - | 1 | E |
| Kuahiwi laukahi | Plantago hawaiensis | - | 1 | E |
| Kuahiwi laukahi | Plantago princeps | - | 1 | E |
| Kuawawaenohu | Alsinidendron lychnoides | - | 1 | E |
| Kula wahine noho | Isodendrion pyrifolium | - | 1 | E |
| Kulu`i | Nototrichium humile | - | 1 | E |
| Lace bug, [unnamed] | Acalyptera susanae | - | 4 | SC |
| Lacewing, Cheese-weed moth | Oliarces clara | - | 1 | SC |
| Lacewing, Cookes' brown | Micromus cookeorum | - | 1 | SC |
| Lacewing, Haleakala micromus brown | Micromus haleakalae | - | 1 | SC |
| Lacewing, lobe-wing brown | Micromus lobipennis | - | 1 | SC |
| Lacewing, San Francisco | Nothochrysa californica | - | 1 | SC |
| Lacewing, Swezey's brown | Micromus swezeyi | - | 1 | SC |
| Lacewing, Usinger's brown | Pseudopsectra usingeri | - | 1 | SC |
| Ladies'-tresses, Ash Meadows | Spiranthes infernalis | - | 1 | SC |
| Ladies'-tresses, Canelo Hills | Spiranthes delitescens | - | 2 | E |
| Ladies'-tresses, Navasota | Spiranthes parksii | - | 2 | E |
| Ladies'-tresses, Ute | Spiranthes diluvialis | - | 6 | T |
| Ladies'-tresses, [unnamed] | Spiranthes lanceolata paludicola | - | 4 | SC |
| Ladies'-tresses, [unnamed] | Spiranthes polyantha | - | 4 | SC |
| Lady's-slipper, California | Cypripedium californicum | - | 1 | RT |
| Lady's-slipper, clustered | Cypripedium fasciculatum | - | 1 | SC |
| Lady's-slipper, mountain | Cypripedium montanum | - | 1 | RT |
| Lady's-slipper, ram's-head | Cypripedium arietinum | - | 3 | RT |
| Lady's-slipper, small white | Cypripedium candidum | - | 3 | RT |
| Lady's-slipper, [unnamed] | Cypripedium kentuckiense | - | 4 | SC |
| Lampmussel, Alabama | Lampsilis virescens | Entire Range; Except where listed as Experimental Populations | 4 | E |
| Lampmussel, Alabama | Lampsilis virescens | U.S.A. (AL;The free-flowing reach of the Tennessee R. from the base of Wilson Dam downstream to the backwaters of Pickwick Reservoir [about 12 RM (19 km)] and the lower 5 RM [8 km] of all tributaries to this reach in Colbert and Lauderdale Cos., see 17.85(a)) | 4 | EXPN |
| Lampmussel, Haddleton | Lampsilis haddletoni | - | 4 | SC |
| Lampmussel, yellow | Lampsilis cariosa | - | 5 | SC |
| Lamprey, Goose Lake | Lampetra tridentata ssp. | Goose Lake | 1 | SC |
| Lamprey, Kern brook | Lampetra hubbsi | - | 1 | RT |
| Lamprey, Miller Lake | Lampetra minima | - | 1 | RT |
| lamprey, Pacific | lampetra tridentata | - | 4 | SC |
| Lamprey, Pacific | Lampetra tridentata ssp. | Pacific | 1 | RT |
| Lamprey, river | Lampetra ayresi | - | 1 | RT |
| Lamprey, western brook | Lampetra richardsoni | - | 1 | RT |
| Lance, Altamaha | Elliptio shepardiana | - | 4 | SC |
| Lance, Florida | Elliptio waltoni | - | 4 | SC |
| Lance, Waccamaw | Elliptio sp. | - | 4 | SC |
| Lance, yellow | Elliptio lanceolata | - | 4 | SC |
| Langur, capped | Trachypithecus (=Presbytis) pileatus | - | Foreign | E |
| Langur, Douc | Pygathrix nemaeus | - | Foreign | E |
| Langur, Francois' | Trachypithecus (=Presbytis) francoisi | - | Foreign | E |
| Langur, golden | Trachypithecus (=Presbytis) geei | - | Foreign | E |
| Langur, gray (=entellus) | Semnopithecus (=Presbytis) entellus | - | Foreign | E |
| Langur, long-tailed | Presbytis potenziani | - | Foreign | T |
| Langur, Pagi Island | Nasalis concolor | - | Foreign | E |
| Langur, purple-faced | Presbytis senex | - | Foreign | T |
| Lanx, shortface | Fisherola nuttalli | - | 1 | RT |
| Laphamia, Hanaupah | Perityle villosa | - | 1 | SC |
| Laphamia, Inyo | Perityle inyoensis | - | 1 | SC |
| Larch, Chilean false | Fitzroya cupressoides | - | Foreign | T |
| Lark, California horned | Eremophila alpestris actia | - | 1 | RT |
| Lark, Raso | Alauda razae | - | Foreign | E |
| Larkspur | Delphinium leucophaeum | - | 1 | SC |
| Larkspur, Alabama | Delphinium alabamicum | - | 4 | RT |
| Larkspur, Baker's | Delphinium bakeri | - | 8 | E |
| Larkspur, Cuyamaca | Delphinium hesperium cuyamacae | - | 1 | SC |
| Larkspur, dune | Delphinium parryi blochmaniae | - | 1 | SC |
| Larkspur, Hospital Canyon | Delphinium californicum interius | - | 1 | SC |
| Larkspur, Mt. Pinos | Delphinium parishii purpureum | - | 1 | RT |
| Larkspur, northwestern | Delphinium xantholeucum | - | 1 | RT |
| Larkspur, peacock | Delphinium pavonaceum | - | 1 | SC |
| larkspur, Recurved | calochortus pulchellus | - | 6 | SC |
| Larkspur, recurved | Delphinium recurvatum | - | 1 | SC |
| Larkspur, San Clemente Island | Delphinium variegatum ssp. kinkiense | - | 8 | E |
| Larkspur, tall | Delphinium exaltatum | - | 4 | SC |
| Larkspur, Thorne's royal | Delphinium variegatum thornei | - | 1 | SC |
| Larkspur, unexpected | Delphinium inopinum | - | 1 | RT |
| Larkspur, Wenatchee | Delphinium viridescens | - | 1 | SC |
| Larkspur, yellow | Delphinium luteum | - | 8 | E |
| Larkspur, [unnamed] | Delphinium multiplex | - | 1 | RT |
| Larkspur, [unnamed] | Delphinium newtonianum | - | 4 | RT |
| Larkspur, [unnamed] | Delphinium nuttallianum lineapetalum | - | 1 | RT |
| Larkspur, [unnamed] | Delphinium treleasei | - | 4 | RT |
| Lathyrus, two-flowered | Lathyrus biflorus | - | 1 | RT |
| Lau `ehu | Panicum niihauense | - | 1 | E |
| Laulihilihi | Schiedea stellarioides | - | 1 | E |
| Layia, beach | Layia carnosa | - | 8 | E |
| Layia, Comanche | Layia leucopappa | - | 1 | SC |
| Layia, Jones | Layia jonesii | - | 1 | SC |
| Layia, pale-yellow | Layia heterotricha | - | 1 | SC |
| Layia, rayless | Layia discoidea | - | 1 | SC |
| Layia, Ziegler's | Layia ziegleri | - | 1 | SC |
| Lead-plant, Carolina | Amorpha georgiana confusa | - | 4 | SC |
| Lead-plant, Crenulate | Amorpha crenulata | - | 4 | E |
| Lead-plant, Georgia | Amorpha georgiana georgiana | - | 4 | SC |
| Leaf miner, chestnut | Tischeria perplexa | - | 5 | SC |
| Leaf miner, Necker petrochroan | Petrochroa neckerensis | - | 1 | SC |
| Leaf mining moth, Oahu opuhe | Philodoria ureraella | - | 1 | SC |
| Leaf-cup, cossatot | Polymnia cossatotensis | - | 4 | SC |
| Leaf-flower, heather | Phyllanthus ericoides | - | 2 | SC |
| Leafhopper, Barrens sedge | Limotettix sp. | - | 5 | SC |
| Leafhopper, redveined prairie | Aflexia rubranura | - | 3 | SC |
| Leafroller, Greenbanded 'ohe'ohe | Spheterista pterotropiana | - | 1 | SC |
| Leafroller, Hawaiian bean | Omoides monogona | - | 1 | SC |
| Leafroller, Wailupe | Spheterista reynoldsiana | - | 1 | SC |
| Leafroller, `Ohe`ohe | Spheterista oheoheana | - | 1 | SC |
| Leafshell | Epioblasma flexuosa | - | 4 | RT |
| Leafshell, Cumberland | Epioblasma stewardsoni | - | 4 | RT |
| Leafy-daisy, Blockman's | Erigeron foliosus blochmaniae | - | 1 | RT |
| Leastdaisy, mat | Chaetopappa hersheyi | - | 2 | SC |
| Leather flower, Alabama | Clematis socialis | - | 4 | E |
| Leather flower, Morefield's | Clematis morefieldii | - | 4 | E |
| Leather flower, [unnamed] | Clematis occidentalis dissecta | - | 1 | RT |
| Leatherflower, Arizona | Clematis hirsutissima arizonica | - | 2 | RT |
| Leatherflower, Millboro | Clematis viticaulis | - | 5 | SC |
| Leatherflower, white-haired | Clematis albicoma | - | 5 | RT |
| Lechwe, red | Kobus leche | - | Foreign | T |
| Legenere | Legenere limosa | - | 1 | SC |
| lehua makanoe | Lysimachia daphnoides | - | 1 | E |
| Leiodid, blind cave | Glacicavicola bathysciodes | - | 1 | SC |
| Lemming, Dismal Swamp (=southern bog) | Synaptomys cooperi helaletes | - | 5 | RT |
| Lemming, Kansas bog | Synaptomys cooperi paludis | - | 6 | RT |
| Lemming, Nebraska bog | Synaptomys cooperi relictus | - | 6 | RT |
| Lemming, northern bog | Synaptomys borealis sphagnicola | - | 5 | SC |
| Lemurs | Lemuridae (incl. genera Lemur, Phaner, Hapalemur, Lepilemur, Microcebus, Allocebus, Cheirogaleus, Varecia) | - | Foreign | E |
| Leopard | Panthera pardus | Wherever found, except where it is listed as Threatened as set forth below | Foreign | E |
| Leopard | Panthera pardus | In Africa, in the wild, south of, and including, the following countries: Gabon, Congo, Zaire, Uganda, Kenya | Foreign | T |
| Leopard, clouded | Neofelis nebulosa | - | Foreign | E |
| Leopard, snow | Uncia (=Panthera) uncia | - | Foreign | E |
| Leptodactylon, sp. nov. ined. | Leptodactylon sp. | - | 6 | SC |
| Lessingia, San Francisco | Lessingia germanorum (=L.g. var. germanorum) | - | 8 | E |
| Lessingia, Warner Springs | Lessingia glandulifera tomentosa | - | 1 | SC |
| Lewisia, Cantelow's | Lewisia cantelowii | - | 1 | RT |
| Lewisia, Congdon's | Lewisia congdonii | - | 1 | RT |
| Lewisia, fringed (unnamed ssp.) | Lewisia cotyledon ssp. | - | 1 | RT |
| Lewisia, Heckner's | Lewisia cotyledon heckneri | - | 1 | SC |
| Lewisia, Howell's | Lewisia cotyledon howellii | - | 1 | SC |
| Lewisia, long-petaled | Lewisia longipetala | - | 1 | SC |
| Lewisia, opposite-leaved | Lewisia oppositifolia | - | 1 | RT |
| Lewisia, saw-toothed | Lewisia serrata | - | 1 | SC |
| Lewisia, Stebbins | Lewisia stebbinsii | - | 1 | SC |
| Lichen, Bluff Mountain Reindeer | Cladonia psoromica | - | 4 | SC |
| Lichen, rock gnome | Gymnoderma lineare | - | 4 | E |
| Lichen, splitting yarn | Sulcaria isidiisera | - | 1 | SC |
| Lichen, [unnamed] | Texosporium sancti-jacobi | - | 1 | SC |
| Lilaeopsis, Mason's | Lilaeopsis masonii | - | 1 | SC |
| Lilia de los llanos | Anthericum chandleri | - | 2 | SC |
| Liliwai | Acaena exigua | - | 1 | E |
| Lilliput, pale (pearlymussel) | Toxolasma cylindrellus | - | 4 | E |
| Lilliput, purple | Toxolasma lividus | - | 4 | SC |
| Lilliput, Savannah | Toxolasma pullus | - | 4 | SC |
| Lily, Bolander's | Lilium bolanderi | - | 1 | RT |
| lily, Catalina mariposa | calochortus catalinae | - | 6 | SC |
| Lily, coast | Lilium maritimum | - | 1 | SC |
| Lily, Fairchild's | Lilium fairchildii | - | 1 | RT |
| Lily, Gray's | Lilium grayi | - | 5 | SC |
| Lily, Humboldt | Lilium humboldtii ocellatum | - | 1 | SC |
| Lily, lemon | Lilium parryi | - | 1 | SC |
| Lily, Minnesota dwarf trout | Erythronium propullans | - | 3 | E |
| Lily, panhandle | Lilium iridollae | - | 4 | SC |
| Lily, Pitkin Marsh | Lilium pardalinum ssp. pitkinense | - | 8 | E |
| Lily, small Shasta | Lilium washingtonianum minus | - | 1 | RT |
| Lily, Umpqua mariposa | Calochortus umpquaensis | - | 1 | RT |
| Lily, Vollmer's | Lilium vollmeri | - | 1 | RT |
| Lily, Western | Lilium occidentale | - | 8 | E |
| Lily, Wiggins' | Lilium wigginsii | - | 1 | RT |
| Limpet, Banbury Springs | Lanx sp. | - | 1 | E |
| Linanthus, Baldwin Lake | Linanthus killipii | - | 1 | SC |
| Linanthus, Mt. Tedoc | Linanthus nuttallii howellii | - | 1 | SC |
| Linanthus, Orcutt's | Linanthus orcuttii | - | 1 | SC |
| Linanthus, Plaskett Meadows | Linanthus harknessii condensatus | - | 1 | SC |
| Linanthus, sand | Linanthus arenicola | - | 1 | RT |
| Linanthus, [unnamed] | Linanthus concinnus | - | 1 | SC |
| Linderiella, California | Linderiella occidentalis | - | 1 | RT |
| linderiella, Santa Rosa | Linderiella santarosae | - | 1 | SC |
| Linsang, spotted | Prionodon pardicolor | - | Foreign | E |
| Lion, Asiatic | Panthera leo persica | - | Foreign | E |
| Lioplax, cylindrical (snail) | Lioplax cyclostomaformis | - | 4 | E |
| Lip fern, fibrillose | Cheilanthes fibrillosa | - | 1 | RT |
| Liptooth, horseshoe | Polygyra hippocrepis | - | 2 | SC |
| Liptooth, white | Polygyra peregrina | - | 4 | SC |
| Liveforever, green | Dudleya virens | - | 1 | SC |
| Liveforever, Laguna Beach | Dudleya stolonifera | - | 8 | T |
| Liveforever, many-stemmed | Dudleya multicaulis | - | 1 | SC |
| Liveforever, Pierpoint Springs | Dudleya cymosa costifolia | - | 1 | SC |
| Liveforever, Santa Barbara Island | Dudleya traskiae | - | 8 | E |
| Liveforever, sticky-leaved | Dudleya viscida | - | 1 | RT |
| Liverword, [Unnamed] | Plagiochila sullivantii var. sullivantii | - | 4 | SC |
| Liverwort, Unnamed | Porella pinnata | - | 4 | SC |
| Liverwort, [Unnamed] | Cylindrocolea andersonii | - | 4 | SC |
| Liverwort, [Unnamed] | Plagiochila sharpii | - | 4 | SC |
| Liverwort, [Unnamed] | Plagiochila sullivantii | - | 4 | SC |
| Liverwort, [Unnamed] | Plagiochila sullivantii var. spinigera | - | 4 | SC |
| Liverwort, [Unnamed] | Plagiochila virginica var. caroliniana | - | 4 | SC |
| Liverwort, [Unnamed] | Porella pinnata | - | 4 | SC |
| Liverwort, [Unnamed] | Sphenolobopsis pearsoni | - | 4 | SC |
| Lizard, Baker's worm | Amphisbaena bakeri | - | 4 | RT |
| Lizard, black legless | Anniella pulchra nigra | - | 1 | RT |
| Lizard, blue-tailed ground | Ameiva wetmorei | - | 4 | SC |
| Lizard, blunt-nosed leopard | Gambelia silus | - | 8 | E |
| Lizard, California horned | Phrynosoma coronatum frontale | - | 1 | SC |
| Lizard, Coachella Valley fringe-toed | Uma inornata | - | 8 | T |
| Lizard, Colorado Desert fringed-toed | Uma notata notata | - | 1 | SC |
| Lizard, Cowles fringe-toed | Uma notata rufopunctata | - | 2 | SC |
| Lizard, dunes sagebrush | Sceloporus arenicolus | - | 2 | C |
| Lizard, eastern short-horned | Phrynosoma douglassii brevirostra | - | 6 | SC |
| Lizard, flat-tailed horned | Phrynosoma mcallii | - | 1 | RT |
| Lizard, Florida scrub | Sceloporus woodi | - | 4 | SC |
| Lizard, gila monster | Heloderma suspectum | Utah DPS | 6 | SU |
| Lizard, gila monster | Heloderma suspectum | - | 2 | RT |
| lizard, Granite night | xantusia henshawi | - | 2 | SC |
| lizard, Granite spiny | sceloporus orcutti | - | 2 | SC |
| Lizard, Hierro giant | Gallotia simonyi simonyi | - | Foreign | E |
| Lizard, Ibiza wall | Podarcis pityusensis | - | Foreign | T |
| Lizard, island glass | Ophisaurus compressus | - | 4 | SC |
| Lizard, Island night | Xantusia riversiana | - | 8 | T |
| lizard, Large-spotted leopard | gambelia wislizenii ssp. wislizenii | - | 2 | SC |
| lizard, Long-nosed leopard | gambelia wislizenii | - | 2 | SC |
| Lizard, Maria Island ground | Cnemidophorus vanzoi | - | Foreign | E |
| Lizard, mimic glass | Ophisaurus mimicus | - | 4 | SC |
| Lizard, Mojave fringe-toed | Uma scoparia | Amargosa River population | 8 | SU |
| Lizard, Navassa curley-tailed | Leiocephalus eremitus | - | 4 | RT |
| Lizard, northern sagebrush | Sceloporus graciosus graciosus | - | 6 | SC |
| Lizard, Panamint alligator | Elgaria panamintina | - | 1 | SC |
| Lizard, reticulate collared | Crotaphytus reticulatus | - | 2 | SC |
| Lizard, San Diego horned | Phrynosoma coronatum blainvillii | - | 1 | SC |
| Lizard, sand dune sagebrush | Sceloporus graciosus arenicolous | - | 2 | RT |
| Lizard, sandstone night | Xantusia henshawi gracilis | - | 1 | SC |
| Lizard, Sierra night | Xantusia vigilis sierrae | - | 1 | SC |
| Lizard, silvery legless | Anniella pulchra pulchra | - | 1 | SC |
| Lizard, southern sagebrush | Sceloporus graciosus vandenburgianus | - | 1 | RT |
| Lizard, St. Croix ground | Ameiva polops | - | 4 | E |
| Lizard, Texas horned | Phrynosoma cornutum | - | 2 | SC |
| Llanero coqui | Eleutherodactylus juanariveroi | - | 4 | UR |
| Lobelia, Boykin's | Lobelia boykinii | - | 4 | SC |
| Locoweed, Fassett's | Oxytropis campestris var. chartacea | - | 3 | T |
| Locoweed, Kobuk | Oxytropis kobukensis | - | 7 | RT |
| Locust, Lake Huron | Trimerotropis huroniana | - | 3 | SC |
| Loeflingia, sage-like | Loeflingia squarrosa artemisiarum | - | 1 | RT |
| Logperch, Blotchside | Percina burtoni | - | 5 | SC |
| Logperch, Conasauga | Percina jenkinsi | - | 4 | E |
| Logperch, Roanoke | Percina rex | - | 5 | E |
| Lomatium, Big Pine | Lomatium rigidum | - | 1 | RT |
| Lomatium, Congdon's | Lomatium congdonii | - | 1 | SC |
| Lomatium, Cook's | Lomatium cookii | - | 1 | E |
| Lomatium, Howell's | Lomatium howellii | - | 1 | RT |
| Lomatium, Inyo | Lomatium foeniculaceum inyoense | - | 1 | RT |
| Lomatium, Owens Peak | Lomatium shevockii | - | 1 | SC |
| Lomatium, Peck's | Lomatium peckianum | - | 1 | RT |
| Lomatium, San Nicolas Island | Lomatium insulare | - | 1 | SC |
| Lomatium, Stebbins' | Lomatium stebbinsii | - | 1 | SC |
| Long-horned beetle, ahinahina | Plagiithmysus swezeyanus | - | 1 | SC |
| Long-horned beetle, bidens | Plagithmysus bidensae | - | 1 | SC |
| Long-horned beetle, Bridwell's | Plagithmysus bridwelli | - | 1 | SC |
| Long-horned beetle, Forbes' Kauai | Plagithmysus forbesianus | - | 1 | SC |
| Long-horned beetle, Forbes' Maui | Plagithmysus forbesii | - | 1 | SC |
| Long-horned beetle, Greenwell's | Plagithmysus greenwelli | - | 1 | SC |
| Long-horned beetle, Haas' `iliahi | Plagithmysus haasi | - | 1 | SC |
| Long-horned beetle, Hawaii alani | Plagithmysus vicinus | - | 1 | SC |
| Long-horned beetle, Hawaii clubbed | Plagithmysus claviger | - | 1 | SC |
| Long-horned beetle, Hawaii decorus | Plagithmysus decorus | - | 1 | SC |
| Long-horned beetle, Hawaii elegant | Plagithmysus elegans | - | 1 | SC |
| Long-horned beetle, Hawaii opuhe | Plagithmysus sulphurescens | - | 1 | SC |
| Long-horned beetle, Hawaii podagricus | Plagithmysus podagricus | - | 1 | SC |
| Long-horned beetle, Hawaii uhiuhi | Plagithmysus mezoneuri | - | 1 | SC |
| Long-horned beetle, Kauai annectant | Plagithmysus annectans | - | 1 | SC |
| Long-horned beetle, Kauai holio | Plagithmysus polystictus | - | 1 | SC |
| Long-horned beetle, Kauai kalia | Plagithmysus ignotus | - | 1 | SC |
| Long-horned beetle, Kauai swamp | Plagithmysus paludis | - | 1 | SC |
| Long-horned beetle, Kauai `ahakea | Plagithmysus permundus | - | 1 | SC |
| Long-horned beetle, Kohala | Plagithmysus kohalae | - | 1 | SC |
| Long-horned beetle, Krauss' | Plagithmysus kraussi | - | 1 | SC |
| Long-horned beetle, Kuhns' Oahu | Plagithmysus kuhnsi | - | 1 | SC |
| Long-horned beetle, Lanai `ohi`a | Plagithmysus lanaiensis | - | 1 | SC |
| Long-horned beetle, long-necked | Plagithmysus longicollis | - | 1 | SC |
| Long-horned beetle, Maui alani | Plagithmysus alani | - | 1 | SC |
| Long-horned beetle, Maui dubautia | Plagithmysus dubautianus | - | 1 | SC |
| Long-horned beetle, Maui forest | Plagithmysus sylvai | - | 1 | SC |
| Long-horned beetle, Maui koa | Plagithmysus koae | - | 1 | SC |
| Long-horned beetle, Maui mamaki | Plagithmysus pipturicola | - | 1 | SC |
| Long-horned beetle, Maui similar | Plagithmysus simillimus | - | 1 | SC |
| Long-horned beetle, Maui speculifer | Plagithmysus speculifer | - | 1 | SC |
| Long-horned beetle, Maui wide-necked | Plagithmysus laticollis | - | 1 | SC |
| Long-horned beetle, Maui `akala | Plagithmysus rubi | - | 1 | SC |
| Long-horned beetle, Molokai fractured | Plagithmysus fractus | - | 1 | SC |
| Long-horned beetle, Muir's ala`a | Plagithmysus muiri | - | 1 | SC |
| Long-horned beetle, Nihoa | Plagithmysus nihoae | - | 1 | SC |
| Long-horned beetle, Oahu super | Plagithmysus superstes | - | 1 | SC |
| Long-horned beetle, Ohi`a | Plagithmysus pulvillatus | - | 1 | SC |
| Long-horned beetle, Pilo kea | Plagithmysus platydesmae | - | 1 | SC |
| Long-horned beetle, Rude's | Necydalis rudei | - | 1 | SC |
| Long-horned beetle, simple-necked | Plagithmysus simplicollis | - | 1 | SC |
| Long-horned beetle, sixbanded | Dryobius sexnotatus | - | 4 | SC |
| Long-horned beetle, Swezey's | Plagithmysus swezeyi | - | 1 | SC |
| Long-legged fly, Ko`olau spurwing | Campsicnemus mirabilis | - | 1 | SC |
| Longhorn moth, Opler's | Adella oplerella | - | 1 | RT |
| loon, Common | gavia immer | - | 7 | SC |
| Loon, yellow-billed | Gavia adamsii | - | 7 | C |
| Looper moth, [unnamed] | Euchlaena milnei | - | 5 | SC |
| Looper moth, [unnamed] | Lambdina canitiaria | - | 5 | SC |
| Looper moth, [unnamed] | Lytrosis permagnaria | - | 4 | SC |
| Looper, Hawaiian hopseed | Scotorythra paratactis | - | 1 | RT |
| Looper, Ioxanthan | Kauaiina ioxantha | - | 1 | SC |
| Looper, Kona giant | Scotorythra megalophylla | - | 1 | RT |
| Looper, Ko`olau giant | Scotorythra nesiotes | - | 1 | RT |
| Looper, `Ola`a pepppered | Tritocleis microphylla | - | 1 | RT |
| Loosestrife, Fraser's yellow | Lysimachia fraseri | - | 4 | SC |
| Loosestrife, fringed | Steironema laevigatum | - | 5 | RT |
| Loosestrife, rough-leaved | Lysimachia asperulaefolia | - | 4 | E |
| Loris, lesser slow | Nycticebus pygmaeus | - | Foreign | T |
| Lotus, Otay | Lotus crassifolius otayensis | - | 1 | SC |
| Lotus, red-flowered | Lotus rubriflorus | - | 1 | SC |
| Lousewort, Dudley's | Pedicularis dudleyi | - | 1 | SC |
| Lousewort, Furbish | Pedicularis furbishiae | - | 5 | E |
| Lousewort, Howell's | Pedicularis howellii | - | 1 | RT |
| Love grass, Fosberg's | Eragrostis fosbergii | - | 1 | E |
| Love grass, Maui | Eragrostis mauiensis | - | 1 | RT |
| Love grass, Ni`ihau | Eragrostis niihauensis | - | 1 | RT |
| Love grass, Sanibel | Eragrostis tracyi | - | 4 | SC |
| Lo`ulu | Pritchardia affinis | - | 1 | E |
| Lo`ulu | Pritchardia elliptica | - | 1 | RT |
| Lo`ulu | Pritchardia eriophora | - | 1 | RT |
| Lo`ulu | Pritchardia gaudichaudii | - | 1 | RT |
| Lo`ulu | Pritchardia glabrata | - | 1 | RT |
| Lo`ulu | Pritchardia kaalae | - | 1 | E |
| Lo`ulu | Pritchardia kahanae | - | 1 | RT |
| Lo`ulu | Pritchardia lanaiensis | - | 1 | RT |
| Lo`ulu | Pritchardia montis-kea | - | 1 | RT |
| Lo`ulu | Pritchardia munroi | - | 1 | E |
| Lo`ulu | Pritchardia napaliensis | - | 1 | E |
| Lo`ulu | Pritchardia remota | - | 1 | E |
| Lo`ulu | Pritchardia schattaueri | - | 1 | E |
| Lo`ulu | Pritchardia viscosa | - | 1 | E |
| Lo`ulu, (=Lo`ulu lelo) | Pritchardia hillebrandii | - | 1 | RT |
| Lo`ulu, (=Na`ena`e) | Pritchardia hardyi | - | 1 | E |
| Lupine, Anthony Peak | Lupinus antoninus | - | 1 | SC |
| Lupine, Ashland | Lupinus lepidus var. ashlandensis | - | 1 | UR |
| Lupine, Biddle's | Lupinus biddlei | - | 1 | SC |
| Lupine, clover | Lupinus tidestromii | - | 8 | E |
| Lupine, Cobb Mountain | Lupinus sericatus | - | 1 | RT |
| Lupine, Cusick's | Lupinus cusickii | - | 1 | SC |
| Lupine, DeDecker's | Lupinus padre-crowleyi | - | 1 | SC |
| Lupine, Guadalupe Island | Lupinus guadalupensis | - | 1 | SC |
| Lupine, Gulfcoast | Lupinus westianus | - | 4 | SC |
| Lupine, Holmgren's | Lupinus holmgrenanus | - | 1 | RT |
| Lupine, Hoskett Meadows | Lupinus culbertsonii culbertsonii | - | 1 | RT |
| Lupine, Inyo | Lupinus inyoensis | - | 1 | RT |
| Lupine, Kincaid's | Lupinus sulphureus (=oreganus) ssp. kincaidii (=var. kincaidii) | - | 1 | T |
| Lupine, Mariposa | Lupinus citrinus deflexus | - | 1 | RT |
| Lupine, Milo Baker's | Lupinus milo-bakeri | - | 1 | SC |
| Lupine, Mono Lake | Lupinus duranii | - | 1 | SC |
| Lupine, Nipomo Mesa | Lupinus nipomensis | - | 8 | E |
| Lupine, orange | Lupinus citrinus | - | 1 | SC |
| Lupine, Panamint Mountains | Lupinus magnificus magnificus | - | 1 | SC |
| Lupine, Peirson's | Lupinus peirsonii | - | 1 | RT |
| Lupine, Quincy | Lupinus dalesiae | - | 1 | RT |
| Lupine, San Luis | Lupinus ludovicianus | - | 1 | SC |
| Lupine, Santa Lucia | Lupinus cervinus | - | 1 | RT |
| Lupine, scrub | Lupinus aridorum | - | 4 | E |
| Lupine, shaggy-hair | Lupinus spectabilis | - | 1 | SC |
| Lupine, The Lassics | Lupinus constancei | - | 1 | SC |
| Lupine, Tracy's | Lupinus tracyi | - | 1 | RT |
| Lynx, Canada | Lynx canadensis | U.S.A. (CO, ID, ME, MI, MN, MT, NH, NY, OR, UT, VT, WA, WI, WY) | 6 | T |
| Lynx, Spanish | Felis pardina | - | Foreign | E |
| Lysimachia, sp. nov. ined. | Lysimachia sp. | - | 1 | SC |
| Lysimachia, sp. nov. ined. (Waihoi Valley) | Lysimachia sp. nov. ined. | Waihoi Valley | 1 | RT |
| Macaque, Formosan rock | Macaca cyclopis | - | Foreign | T |
| Macaque, Japanese | Macaca fuscata | - | Foreign | T |
| Macaque, lion-tailed | Macaca silenus | - | Foreign | E |
| Macaque, stump-tailed | Macaca arctoides | - | Foreign | T |
| Macaque, Toque | Macaca sinica | - | Foreign | T |
| Macaw, blue-headed | Primolius couloni | - | Foreign | UR |
| Macaw, blue-throated | Ara glaucogularis | - | Foreign | UR |
| Macaw, glaucous | Anodorhynchus glaucus | - | Foreign | E |
| Macaw, great green | Ara ambiguus | - | Foreign | UR |
| Macaw, hyacinth | Anodorhynchus hyacinthinus | - | Foreign | UR |
| Macaw, indigo | Anodorhynchus leari | - | Foreign | E |
| Macaw, little blue | Cyanopsitta spixii | - | Foreign | E |
| Macaw, military | Ara militaris | - | Foreign | UR |
| Macaw, scarlet | Ara macao | - | Foreign | UR |
| Machaeranthera, Houston | Machaeranthera aurea | - | 2 | SC |
| Machearanthera, Welder | Machaeranthera heterocarpa | - | 2 | SC |
| Madia, Hall's | Madia hallii | - | 1 | SC |
| madia, Showy | madia radiata | - | 6 | SC |
| Madia, Stebbins' | Madia stebbinsii | - | 1 | SC |
| Madtom, Caddo | Noturus taylori | - | 4 | RT |
| Madtom, Carolina | Noturus furiosus | - | 4 | RT |
| Madtom, chucky | Noturus crypticus | - | 4 | PE |
| Madtom, frecklebelly | Noturus munitus | - | 4 | RT |
| Madtom, Neosho | Noturus placidus | - | 6 | T |
| Madtom, orangefin | Noturus gilberti | - | 5 | UR |
| Madtom, Ouachita | Noturus lachneri | - | 4 | RT |
| Madtom, pygmy | Noturus stanauli | U.S.A. (TN - specified portions of the French Broad and Holston Rivers; see 17.84(t)(1)(i)) | 4 | EXPN |
| Madtom, pygmy | Noturus stanauli | - | 4 | E |
| Madtom, saddled | Noturus sp. | saddled | 4 | SC |
| Madtom, Scioto | Noturus trautmani | - | 3 | E |
| Madtom, smoky | Noturus baileyi | Tellico River, between the backwaters of the Tellico Reservoir and the Tellico Ranger Station, in Monroe County, Tennessee | 4 | EXPN |
| Madtom, smoky | Noturus baileyi | Entire | 4 | E |
| Madtom, spotted | Noturus insignis ssp. | - | 5 | SC |
| Madtom, yellowfin | Noturus flavipinnis | Tellico River between the backwaters of the Tellico Reservoir and the Tellico Ranger Station, in Monroe County, Tennessee | 4 | EXPN |
| Madtom, yellowfin | Noturus flavipinnis | Entire, except where listed as an experimental population below | 4 | T |
| Madtom, yellowfin | Noturus flavipinnis | N. Fork Holston R., VA, TN; S. Fork Holston R., upstream to Ft. Patrick Henry Dam, TN; Holston R., downstream to John Sevier Detention Lake Dam, TN; and all tributaries thereto | 4 | EXPN |
| Madtom, yellowfin | Noturus flavipinnis | U.S.A. (TN - specified portions of the French Broad and Holston Rivers; see 17.84(e)(1)(iii)) | 4 | EXPN |
| Magnolia, Ashe's | Magnolia ashei | - | 4 | SC |
| Magpie-robin, Seychelles (thrush) | Copsychus sechellarum | - | Foreign | E |
| Mahoe | Alectryon macrococcus | - | 1 | E |
| maiden fern, Boyds | Christella boydiae | - | 1 | C |
| Maidenbush, Trans-Pecos | Andrachne arida | - | 2 | SC |
| Makou | Botrychium subbifoliatum | - | 1 | SC |
| Makou | Brachionidium ciliolatum | - | 4 | SC |
| Makou | Peucedanum sandwicense | - | 1 | T |
| Makou | Ranunculus hawaiensis | - | 1 | C |
| Makou | Ranunculus mauiensis | - | 1 | C |
| Malacothrix, Carmel Valley | Malacothrix saxatilis arachnoidea | - | 1 | SC |
| Malacothrix, island | Malacothrix squalida | - | 8 | E |
| Malacothrix, Santa Cruz Island | Malacothrix indecora | - | 8 | E |
| Malimbe, Ibadan | Malimbus ibadanensis | - | Foreign | E |
| Malkoha, red-faced (cuckoo) | Phaenicophaeus pyrrhocephalus | - | Foreign | E |
| Mallard, Mariana | Anas oustaleti | - | 1 | D3A |
| mallow, Gierisch | Sphaeralcea gierischii | - | 2 | C |
| Mallow, Island tree | Lavatera assurgentiflora | - | 1 | SC |
| Mallow, Kern | Eremalche kernensis | - | 8 | E |
| Mallow, Peter's Mountain | Iliamna corei | - | 5 | E |
| Mallow, Virginia | Sida hermaphrodita | - | 5 | RT |
| Manaca, palma de | Calyptronoma rivalis | - | 4 | T |
| Manatee, Amazonian | Trichechus inunguis | - | Foreign | E |
| Manatee, West African | Trichechus senegalensis | - | Foreign | T |
| Manatee, West Indian | Trichechus manatus | - | 4 | E |
| Mandrill | Mandrillus (=Papio) sphinx | - | Foreign | E |
| Manena | Melicope cinerea | - | 1 | RT |
| Mangabey, Tana River | Cercocebus galeritus galeritus | - | Foreign | E |
| Mangabey, white-collared | Cercocebus torquatus | - | Foreign | E |
| Manioc, Walker's | Manihot walkerae | - | 2 | E |
| Manna grass, Smoky Mountains | Glyceria nubigena | - | 4 | SC |
| Manzanita, Arroyo de la Cruz | Arctostaphylos cruzensis | - | 1 | SC |
| Manzanita, Baker's | Arctostaphylos bakeri bakeri | - | 1 | RT |
| Manzanita, Bonny Doon | Arctostaphylos silvicola | - | 1 | SC |
| Manzanita, dacite | Arctostaphylos tomentosa daciticola | - | 1 | SC |
| Manzanita, Del Mar | Arctostaphylos glandulosa ssp. crassifolia | - | 8 | E |
| Manzanita, Del Norte | Arctostaphylos nortensis | - | 1 | SC |
| Manzanita, Hearsts' | Arctostaphylos hookeri hearstiorum | - | 1 | SC |
| manzanita, Hooker's | arctostaphylos hookeri ssp. hookeri | - | 6 | SC |
| Manzanita, Ione | Arctostaphylos myrtifolia | - | 8 | T |
| Manzanita, Kamchatka Point | Arctostaphylos uva-ursi suborbiculata | - | 1 | RT |
| Manzanita, Klamath | Arctostaphylos klamathensis | - | 1 | SC |
| Manzanita, Leo Brewer's | Arctostaphylos uva-ursi leobreweri | - | 1 | RT |
| Manzanita, Little Sur | Arctostaphylos edmundsii | - | 1 | SC |
| Manzanita, Marin | Arctostaphylos virgata | - | 1 | RT |
| Manzanita, Mono | Arctostaphylos uva-ursi monoensis | - | 1 | RT |
| Manzanita, Montara | Arctostaphylos montaraensis | - | 1 | SC |
| Manzanita, Monterrey | Arctostaphylos montereyensis | - | 1 | SC |
| Manzanita, Morro | Arctostaphylos morroensis | - | 8 | T |
| Manzanita, Mt. Diablo | Arctostaphylos auriculata | - | 1 | RT |
| Manzanita, Nissenan | Arctostaphylos nissenana | - | 1 | SC |
| Manzanita, Oso | Arctostaphylos osoensis | - | 1 | SC |
| Manzanita, Otay | Arctostaphylos otayensis | - | 1 | SC |
| Manzanita, Pacific | Arctostaphylos pacifica | - | 1 | RT |
| Manzanita, Pajaroensis | Arctostaphylos pajaroensis | - | 1 | SC |
| Manzanita, pallid | Arctostaphylos pallida | - | 8 | T |
| Manzanita, pecho | Arctostaphylos pechoensis | - | 1 | SC |
| Manzanita, Point Reyes | Arctostaphylos uva-ursi marinensis | - | 1 | RT |
| Manzanita, Presidio | Arctostaphylos hookeri var. ravenii | - | 8 | E |
| Manzanita, Raiches | Arctostaphylos stanfordiana raichei | - | 1 | SC |
| manzanita, Rainbow | arctostaphylos rainbowensis | - | 6 | SC |
| Manzanita, Refugio | Arctostaphylos refugioensis | - | 1 | SC |
| Manzanita, San Bruno Mountain | Arctostaphylos imbricata | - | 1 | RT |
| Manzanita, San Francisco | Arctostaphylos franciscana | - | 8 | UR |
| Manzanita, San Gabriel | Arctostaphylos gabrielensis | - | 1 | SC |
| Manzanita, sand mesa | Arctostaphylos rudis | - | 1 | SC |
| Manzanita, sandmat | Arctostaphylos pumila | - | 1 | SC |
| Manzanita, Santa Catalina Island | Arctostaphylos catalinae | - | 1 | SC |
| Manzanita, Santa Cruz | Arctostaphylos andersonii | - | 1 | SC |
| Manzanita, Santa Lucia | Arctostaphylos luciana | - | 1 | SC |
| Manzanita, Santa Margarita | Arctostaphylos pilosula pilosula | - | 1 | SC |
| Manzanita, Santa Rosa Island | Arctostaphylos confertiflora | - | 8 | E |
| Manzanita, Schreiber's | Arabis oxylobula | - | 6 | RT |
| Manzanita, Schreiber's | Arctostaphylos glutinosa | - | 1 | SC |
| Manzanita, Tamalpais | Arctostaphylos hookeri montana | - | 1 | SC |
| Manzanita, Vine Hill | Arctostaphylos densiflora | - | 1 | SC |
| Manzanita, [unnamed] | Arctostaphylos hispidula | - | 1 | RT |
| Manzanita, [unnamed] | Arctostaphylos intricata oblongifolia | - | 1 | RT |
| Mapele | Cyrtandra cyaneoides | - | 1 | E |
| Maple, [unnamed] | Acer grandidentatum sinuosum | - | 2 | RT |
| Mapleleaf, winged | Quadrula fragosa | U.S.A. (AL; the free-flowing reach of the Tennessee R. from the base of Wilson Dam downstream to the backwaters of Reservoir [about 12 RM (19 km)] and the lower 5 RM [8 km] of all tributaries to this reach in Colbert and Lauderdale. See 17.85(a)) | 4 | EXPN |
| Mapleleaf, winged | Quadrula fragosa | Entire; except where listed as experimental populations | 3 | E |
| Maraca | Canna pertusa | - | 4 | SC |
| Margay | Leopardus (=Felis) wiedii | Mexico southward | Foreign | E |
| Margay, Texas | Leopardus wiedii cooperi | - | 2 | RT |
| Maricao cimarron | Byrsonima lucida | - | 4 | SC |
| Maricao cimarron | Byrsonima spicata | - | 4 | SC |
| Marina, California | Marina orcuttii orcuttii | - | 1 | SC |
| Mariposa lily | Calochortus simulans | - | 1 | RT |
| Mariposa lily | Calochortus venustus sanguineus | - | 1 | RT |
| Mariposa lily, alkali | Calochortus striatus | - | 1 | SC |
| Mariposa lily, Arroyo de la Cruz | Calochortus clavatus recurvifolius | - | 1 | SC |
| Mariposa lily, Cox's | Calochortus coxii | - | 1 | SC |
| Mariposa lily, Dunn's | Calochortus dunnii | - | 1 | SC |
| Mariposa lily, foothill | Calochortus weedii intermedius | - | 1 | SC |
| Mariposa lily, Greene's | Calochortus greenei | - | 1 | SC |
| Mariposa lily, Howell's | Calochortus howellii | - | 1 | SC |
| Mariposa lily, Inyo | Calochortus excavatus | - | 1 | SC |
| Mariposa lily, Munz's | Calochortus palmeri munzii | - | 1 | SC |
| Mariposa lily, Palmer's | Calochortus palmeri palmeri | - | 1 | SC |
| Mariposa lily, Pleasant Valley | Calochortus clavatus avius | - | 1 | SC |
| Mariposa lily, Plummer's | Calochortus plummerae | - | 1 | SC |
| Mariposa lily, Shasta River | Calochortus monanthus | - | 1 | SC |
| Mariposa lily, Shirley Meadows | Calochortus westonii | - | 1 | SC |
| Mariposa lily, Siskiyou | Calochortus persistens | - | 8 | C |
| Mariposa lily, slender | Calochortus clavatus gracilis | - | 1 | SC |
| Mariposa lily, Tiburon | Calochortus tiburonensis | - | 8 | T |
| Mariposa lily, [unnamed] | Calochortus indecorus | - | 1 | SC |
| Mariposa, long-bearded, Peck's | Calochortus longebarbatus peckii | - | 1 | SC |
| Mariposa, San Luis | Calochortus obispoensis | - | 1 | RT |
| Markhor | Capra falconeri | - | Foreign | UR |
| Markhor, chiltan (=wild goat) | Capra falconeri (=aegragrus) chiltanensis | - | Foreign | E |
| Markhor, Kabul | Capra falconeri megaceros | - | Foreign | E |
| Markhor, straight-horned | Capra falconeri jerdoni | Entire | Foreign | E |
| Markhor, straight-horned | Capra falconeri jerdoni | population of the Torghar Hills region of Balochistan Province, Pakistan | Foreign | UR |
| Marmoset, buff-headed | Callithrix flaviceps | - | Foreign | E |
| Marmoset, cotton-top | Saguinus oedipus | - | Foreign | E |
| Marmoset, Goeldi's | Callimico goeldii | - | Foreign | E |
| Marmoset, white-eared (=buffy tufted-ear) | Callithrix aurita (=jacchus a.) | - | Foreign | E |
| Marmot, Vancouver Island | Marmota vancouverensis | - | Foreign | E |
| Marmot, Wet Mountains yellow-bellied | Marmota flaviventris notioros | - | 6 | RT |
| Marsh elder, San Diego | Iva hayesiana | - | 1 | SC |
| Marshsnail, Fish Springs | Stagnicola pilsbryi | - | 6 | RT |
| Marstonia, beaver pond | Pyrgulopsis castor | - | 4 | SC |
| Marstonia, Ocmulgee | Pyrgulopsis agarhecta | - | 4 | SC |
| Marstonia, olive | Pyrgulopsis olivacea | - | 4 | SC |
| Marstonia, royal (snail) | Pyrgulopsis ogmorhaphe | - | 4 | E |
| Marsupial, eastern jerboa | Antechinomys laniger | - | Foreign | E |
| Marsupial-mouse, large desert | Sminthopsis psammophila | - | Foreign | E |
| Marsupial-mouse, long-tailed | Sminthopsis longicaudata | - | Foreign | E |
| Marten, eastern | Martes americana americana | - | 5 | RT |
| Marten, Formosan yellow-throated | Martes flavigula chrysospila | - | Foreign | E |
| martin, Purple | progne subis | - | 7 | SC |
| Massasauga (=rattlesnake), eastern | Sistrurus catenatus catenatus | - | 3 | C |
| Mastiff-bat, Florida | Eumops glaucinus floridanus | - | 4 | SC |
| Mastiff-bat, greater western | Eumops perotis californicus | - | 2 | SC |
| Mastiff-bat, Underwood's | Eumops underwoodi | - | 2 | SC |
| Matchweed, Bay | Gutierrezia californica | - | 1 | RT |
| Mato, amarillo | Caesalpinia culebrae | - | 4 | SC |
| Mato, braun | Caesalpinia portoricensis | - | 4 | RT |
| Mato, negro | Caesalpinia monensis | - | 4 | RT |
| Mayfly Konza Prairie | Leptophlebia konza | - | 6 | SC |
| Mayfly, American sandburrowing | Dolania americana | - | 4 | SC |
| Mayfly, argo ephemerellan | Ephemerella argo | - | 3 | SC |
| Mayfly, Berner's two-winged | Heterocleon berneri | - | 4 | SC |
| Mayfly, Blackwater sandfiltering | Homoeoneuria dolani | - | 4 | SC |
| Mayfly, burrowing | Hexagenia sp | - | NA | RT |
| Mayfly, Cahaba sandfiltering | Homoeoneuria cahabensis | - | 4 | SC |
| Mayfly, Colorado burrowing | Ephemera compar | - | 6 | RT |
| Mayfly, diverse isonychian | Isonychia diversa | - | 4 | RT |
| Mayfly, false ameletus | Ameletus falsus | - | 2 | SC |
| Mayfly, Frison's seratellan | Seratella frisoni | - | 3 | SC |
| Mayfly, Meridion blackwater | Pseudirion meridionalis | - | 4 | RT |
| Mayfly, Pecatonica River | Acanthometropus pecatonica | - | 3 | SC |
| Mayfly, robust pentagenian burrowing | Pentagenia robusta | - | 3 | RT |
| Mayfly, spiculose seratellan | Seratella spiculosa | - | 4 | SC |
| Mayfly, Tomah | Siphlonisca aerodromia | - | 5 | SC |
| Mayfly, Wallace's deepwater | Spinadis wallacei | - | 3 | SC |
| Mayfly, West Virginia burrowing | Ephemera triplex | - | 5 | SC |
| Mayfly, yellow brachycercus | Brachycercus flavus | - | 4 | SC |
| Mayfly, [unnamed] | Paraleptophlebia calcarica | - | 4 | SC |
| Ma`o hau hele, (=native yellow hibiscus) | Hibiscus brackenridgei | - | 1 | E |
| Ma`ohi`ohi | Stenogyne rugosa subulata | - | 1 | RT |
| Ma`oli`oli | Schiedea amplexicaulis | - | 1 | RT |
| Ma`oli`oli | Schiedea apokremnos | - | 1 | E |
| Ma`oli`oli | Schiedea globosa foliosior | - | 1 | RT |
| Ma`oli`oli | Schiedea globosa globosa | - | 1 | RT |
| Ma`oli`oli | Schiedea globosa graminifolia | - | 1 | RT |
| Ma`oli`oli | Schiedea hawaiiensis | - | 1 | RT |
| Ma`oli`oli | Schiedea kealiae | - | 1 | E |
| Ma`oli`oli | Schiedea ligustrina nematopoda | - | 1 | RT |
| Ma`oli`oli | Schiedea pubescens | - | 1 | C |
| Ma`oloa | Neraudia melastomifolia | - | 1 | RT |
| Meadow-rue, Piedmont | Thalictrum macrostylum | - | 4 | SC |
| Meadowbeauty, awned | Rhexia aristosa | - | 4 | SC |
| Meadowbeauty, panhandle | Rhexia salicifolia | - | 4 | SC |
| Meadowbeauty, [unnamed] | Rhexia parviflora | - | 4 | SC |
| Meadowfoam, Baker's | Limnanthes bakeri | - | 1 | SC |
| Meadowfoam, Bellinger's | Limnanthes floccosa bellingeriana | - | 1 | SC |
| Meadowfoam, Butte County | Limnanthes floccosa ssp. californica | - | 8 | E |
| Meadowfoam, dwarf | Limnanthes floccosa ssp. pumila | - | 1 | SC |
| Meadowfoam, large-flowered woolly | Limnanthes floccosa ssp. grandiflora | - | 1 | E |
| Meadowfoam, Parish's | Limnanthes gracilis parishii | - | 1 | RT |
| Meadowfoam, Point Reyes | Limnanthes douglasii sulphurea | - | 1 | SC |
| Meadowfoam, Sebastopol | Limnanthes vinculans | - | 8 | E |
| Meadowfoam, slender | Lasthenia macrantha prisca | - | 1 | SC |
| Meadowrue, Cooley's | Thalictrum cooleyi | - | 4 | E |
| Meadowrue, Houston | Thalictrum texanum | - | 2 | SC |
| Meadowrue, Steele's | Thalictrum steeleanum | - | 5 | RT |
| Mealybug, Oahu abutilon clavicoccus | Clavicoccus erinaceus | - | 1 | SC |
| Mealybug, Oahu iliahi gall | Phyllococcus antricolens | - | 1 | SC |
| Mealybug, Oahu ke`oke`o clavicoccus | Clavicoccus tribulus | - | 1 | SC |
| Mealybug, Opuhe gall | Phyllococcus oahuensis | - | 1 | SC |
| Megapode, Maleo | Macrocephalon maleo | - | Foreign | E |
| Megapode, Micronesian | Megapodius laperouse | - | 1 | E |
| megomphix, Oregon | megomphix hemphilli | entire | 1 | SC |
| Mehamehame | Flueggea neowawraea | - | 1 | E |
| Mercury, wild, Hill Country | Argythamnia aphoroides | - | 2 | SC |
| Mercury, wild, silvery | Argythamnia argyraea | - | 2 | RT |
| Merganser, Brazillian | Mergus octosetaceus | - | Foreign | PE |
| Merlin | falco columbarius | - | 7 | SC |
| Merolonche, Doll's | Merolonche dolli | - | 5 | SC |
| Mesa-mint, Otay | Pogogyne nudiuscula | - | 8 | E |
| Mesa-mint, San Diego | Pogogyne abramsii | - | 8 | E |
| Mescal bean, Guadalupe Mountains | Sophora gypsophila guadalupensis | - | 2 | RT |
| Meshweaver, Braken Bat Cave | Cicurina venii | - | 2 | E |
| Meshweaver, Government Canyon Bat Cave | Cicurina vespera | - | 2 | E |
| Meshweaver, Madla's Cave | Cicurina madla | - | 2 | E |
| Meshweaver, Robber Baron Cave | Cicurina baronia | - | 2 | E |
| Meshweaver, Warton cave | Cicurina wartoni | - | 2 | C |
| Micranthemum, Nuttall's | Micranthemum micranthemoides | - | 5 | SC |
| Micro caddisfly, Alsea ochrotrichian | Ochrotrichia alsea | - | 1 | RT |
| Micro caddisfly, contorted ochrotrichian | Ochrotrichia contorta | - | 4 | SC |
| Micro caddisfly, Deschutes ochrotrichian | Ochrotrichia phenosa | - | 1 | SC |
| Micro caddisfly, Florida oxyethiran | Oxyethira florida | - | 4 | SC |
| Micro caddisfly, Kite's neotrichian | Neotrichia kitae | - | 3 | SC |
| Micro caddisfly, Knoxville hydroptilan | Hydroptila decia | - | 4 | RT |
| Micro caddisfly, Page Spring | Metrichia volada | - | 2 | SC |
| Micro caddisfly, Provost's ochrotrichian | Ochrotrichia provosti | - | 4 | SC |
| Micro caddisfly, Vertrees's ochrotrichian | Ochrotrichia vertreesi | - | 1 | SC |
| Microcaddisfly, Susan's purse-making | Ochrotrichia susanae | - | 6 | RT |
| Microseris, Santa Cruz | Microseris decipiens | - | 1 | SC |
| microseris, Small-flowered | microseris douglasii ssp. platycarpha | - | 6 | SC |
| milk-vetch, Alkali | Astragalus tener var. tener | - | 1 | SC |
| Milk-vetch, Applegate's | Astragalus applegatei | - | 8 | E |
| Milk-vetch, Ash meadows | Astragalus phoenix | - | 8 | T |
| Milk-vetch, Barneby | Astragalus barnebyi | - | 6 | RT |
| Milk-vetch, Bear Valley | Astragalus lentiginosus ursinus | - | 6 | RT |
| Milk-vetch, Beath | Astragalus beathii | - | 2 | RT |
| Milk-vetch, Beatley | Astragalus beatleyae | - | 1 | RT |
| Milk-vetch, Big Bear | Astragalus lentiginosus sierrae | - | 1 | SC |
| Milk-vetch, Braunton's | Astragalus brauntonii | - | 8 | E |
| Milk-vetch, Calloway | Astragalus callithrix | - | 1 | RT |
| Milk-vetch, Castetter | Astragalus castetteri | - | 2 | RT |
| Milk-vetch, Clara Hunt's | Astragalus clarianus | - | 8 | E |
| Milk-vetch, cliff | Astragalus cremnophylax myriorrhaphis | - | 2 | SC |
| Milk-vetch, cliff-palace | Astragalus deterior | - | 6 | SC |
| Milk-vetch, Coachella Valley | Astragalus lentiginosus var. coachellae | - | 8 | E |
| Milk-vetch, coastal dunes | Astragalus tener var. titi | - | 8 | E |
| Milk-vetch, Columbia | Astragalus columbianus | - | 1 | SC |
| Milk-vetch, coppermine | Astragalus cobrensis maguirei | - | 2 | SC |
| Milk-vetch, Cottam | Astragalus cottamii | - | 2 | RT |
| milk-vetch, Cotton's | Astragalus cottonii | - | 1 | SC |
| Milk-vetch, Cronquist | Astragalus cronquistii | - | 6 | SC |
| Milk-vetch, curve-podded Mojave | Astragalus mohavensis hemigyrus | - | 1 | SC |
| Milk-vetch, Cushenbury | Astragalus albens | - | 8 | E |
| Milk-vetch, Deane's | Astragalus deanei | - | 1 | SC |
| milk-vetch, Debeque | Astragalus debequaeus | - | 6 | RT |
| Milk-vetch, debris | Astragalus detritalis | - | 6 | RT |
| Milk-vetch, Descanso | Astragalus oocarpus | - | 1 | SC |
| Milk-vetch, Deseret | Astragalus desereticus | - | 6 | T |
| Milk-vetch, dinosaur | Astragalus saurinus | - | 6 | RT |
| Milk-vetch, Duchesne | Astragalus duchesnensis | - | 6 | RT |
| Milk-vetch, Ertter's | Astragalus ertterae | - | 1 | SC |
| Milk-vetch, escarpment | Astragalus striatiflorus | - | 6 | RT |
| milk-vetch, Ferris' | Astragalus tener var. ferrisae | - | 1 | SC |
| Milk-vetch, Fish Slough | Astragalus lentiginosus var. piscinensis | - | 8 | T |
| Milk-vetch, gladiator | Astragalus xiphoides | - | 2 | SC |
| Milk-vetch, Grand Junction | Astragalus linifolius | - | 6 | RT |
| Milk-vetch, grass | Astragalus chloodes | - | 6 | RT |
| Milk-vetch, gumbo | Astragalus ampullarius | - | 6 | SC |
| Milk-vetch, Gunnison | Astragalus anisus | - | 6 | SC |
| Milk-vetch, gypsum | Astragalus gypsodes | - | 2 | RT |
| Milk-vetch, Hamilton | Astragalus hamiltonii | - | 6 | UR |
| Milk-vetch, heliotrope | Astragalus montii | - | 6 | T |
| Milk-vetch, Holmgren | Astragalus holmgreniorum | - | 6 | E |
| Milk-vetch, horseshoe | Astragalus equisolensis | - | 6 | RT |
| Milk-vetch, Humboldt | Astragalus agnicidus | - | 1 | SC |
| Milk-vetch, Isely | Astragalus iselyi | - | 6 | UR |
| Milk-vetch, Jacumba | Astragalus douglasii perstrictus | - | 1 | SC |
| Milk-vetch, Jaeger's bush | Astragalus pachypus jaegeri | - | 1 | SC |
| Milk-vetch, Jesup's | Astragalus robbinsii var. jesupi | - | 5 | E |
| Milk-vetch, Kaiparowits | Astragalus malacoides | - | 6 | RT |
| Milk-vetch, Kerr's | Astragalus kerrii | - | 2 | SC |
| Milk-vetch, Lane Mountain | Astragalus jaegerianus | - | 8 | E |
| Milk-vetch, Lavin's | Astragalus oophorus lavinii | - | 1 | SC |
| Milk-vetch, Long Valley | Astragalus johannis-howellii | - | 1 | RT |
| Milk-vetch, Mancos | Astragalus humillimus | - | 2 | E |
| Milk-vetch, Mono | Astragalus monoensis monoensis | - | 1 | SC |
| Milk-vetch, Mulford's | Astragalus mulfordiae | - | 1 | SC |
| Milk-vetch, naturita | Astragalus naturitensis | - | 6 | RT |
| Milk-vetch, Nutriosa | Astragalus nutriosensis | - | 2 | SC |
| Milk-vetch, Osgood Mountains | Astragalus yoder-williamsii | - | 1 | UR |
| Milk-vetch, Osterhout | Astragalus osterhoutii | - | 6 | E |
| Milk-vetch, pauper | Astragalus misellus pauper | - | 1 | RT |
| Milk-vetch, Peirson's | Astragalus magdalenae var. peirsonii | - | 8 | T |
| Milk-vetch, Raven's | Astragalus monoensis ravenii | - | 1 | SC |
| Milk-vetch, Ripley | Astragalus ripleyi | - | 2 | SC |
| Milk-vetch, Robbins, | Astragalus robbinsii alpiniformis | - | 1 | RT |
| Milk-vetch, Robbins, | Astragalus robbinsii robbinsii | - | 5 | RT |
| Milk-vetch, Robbins, western ssp. | Astragalus robbinsii occidentalis | - | 1 | SC |
| Milk-vetch, Rydberg | Astragalus perianus | - | 6 | DO |
| Milk-vetch, San Clemente Island | Astragalus nevinii | - | 1 | SC |
| Milk-vetch, San Pitch Valley | Astragalus lentiginosus chartaceus | - | 1 | RT |
| Milk-vetch, San Rafael | Astragalus rafaelensis | - | 6 | RT |
| Milk-vetch, sandhills | Astragalus michauxii | - | 4 | SC |
| Milk-vetch, Schmoll | Astragalus schmolliae | - | 6 | UR |
| Milk-vetch, Sentry | Astragalus cremnophylax var. cremnophylax | - | 2 | E |
| Milk-vetch, Shevock's | Astragalus shevockii | - | 1 | RT |
| Milk-vetch, shining | Astragalus lentiginosus micans | - | 1 | RT |
| Milk-vetch, Shivwits | Astragalus ampullarioides | - | 6 | E |
| Milk-vetch, Sleeping Ute | Astragalus tortipes | - | 6 | C |
| Milk-vetch, Sodaville | Astragalus lentiginosus sesquimetralis | - | 1 | RT |
| Milk-vetch, Spring Mountain | Astragalus remotus | - | 1 | SC |
| Milk-vetch, sterile | Astragalus sterilis | - | 1 | UR |
| Milk-vetch, thistle, Douglas' | Astragalus kentrophyta douglasii | - | 1 | RT |
| Milk-vetch, Tiehm's | Astragalus tiehmii | - | 1 | SC |
| Milk-vetch, Tonopah | Astragalus iodanthus pseudoiodanthus | - | 1 | RT |
| Milk-vetch, Trask's | Astragalus traskiae | - | 1 | SC |
| Milk-vetch, triple-ribbed | Astragalus tricarinatus | - | 8 | E |
| Milk-vetch, Ventura Marsh | Astragalus pycnostachyus var. lanosissimus | - | 8 | E |
| Milk-vetch, weak | Astragalus solitarius | - | 1 | SC |
| Milk-vetch, Webber's | Astragalus webberi | - | 1 | SC |
| Milk-vetch, Wetherill | Astragalus wetherillii | - | 6 | RT |
| Milk-vetch, Whited | Astragalus sinuatus | - | 1 | SC |
| Milk-vetch, withered wooly | Astragalus mollissimus marcidus | - | 2 | SC |
| Milk-vetch, [unnamed] | Astragalus accumbens | - | 2 | RT |
| Milk-vetch, [unnamed] | Astragalus ackermannii | - | 1 | RT |
| Milk-vetch, [unnamed] | Astragalus aequalis | - | 1 | SC |
| Milk-vetch, [unnamed] | Astragalus altus | - | 2 | RT |
| Milk-vetch, [unnamed] | Astragalus alvordensis | - | 1 | RT |
| Milk-vetch, [unnamed] | Astragalus amnis-amissi | - | 1 | RT |
| Milk-vetch, [unnamed] | Astragalus atratus inseptus | - | 1 | SC |
| Milk-vetch, [unnamed] | Astragalus barrii | - | 6 | RT |
| Milk-vetch, [unnamed] | Astragalus brandegei | - | 6 | SC |
| Milk-vetch, [unnamed] | Astragalus calycosus monophyllidius | - | 1 | RT |
| Milk-vetch, [unnamed] | Astragalus camptopus | - | 1 | RT |
| Milk-vetch, [unnamed] | Astragalus ceramicus apus | - | 1 | RT |
| Milk-vetch, [unnamed] | Astragalus cimae sufflatus | - | 1 | RT |
| Milk-vetch, [unnamed] | Astragalus consobrinus | - | 6 | RT |
| Milk-vetch, [unnamed] | Astragalus convallarius finitimus | - | 1 | RT |
| Milk-vetch, [unnamed] | Astragalus drabelliformis | - | 6 | SC |
| Milk-vetch, [unnamed] | Astragalus ensiformis | - | 6 | RT |
| Milk-vetch, [unnamed] | Astragalus eurylobus | - | 1 | SC |
| Milk-vetch, [unnamed] | Astragalus gilmanii | - | 1 | SC |
| Milk-vetch, [unnamed] | Astragalus harrisonii | - | 6 | RT |
| Milk-vetch, [unnamed] | Astragalus henrimontanensis | - | 6 | RT |
| Milk-vetch, [unnamed] | Astragalus hoodianus | - | 1 | RT |
| Milk-vetch, [unnamed] | Astragalus howellii | - | 1 | SC |
| Milk-vetch, [unnamed] | Astragalus hypoxylus | - | 2 | SC |
| Milk-vetch, [unnamed] | Astragalus knightii | - | 2 | SC |
| Milk-vetch, [unnamed] | Astragalus lancearius | - | 6 | RT |
| Milk-vetch, [unnamed] | Astragalus lentiformis | - | 1 | SC |
| Milk-vetch, [unnamed] | Astragalus lentiginosus latus | - | 1 | RT |
| Milk-vetch, [unnamed] | Astragalus lentiginosus maricopae | - | 2 | RT |
| Milk-vetch, [unnamed] | Astragalus lentiginosus pohlii | - | 6 | SC |
| Milk-vetch, [unnamed] | Astragalus lentiginosus scorpionis | - | 6 | SC |
| Milk-vetch, [unnamed] | Astragalus loanus | - | 6 | RT |
| Milk-vetch, [unnamed] | Astragalus lutosus | - | 6 | RT |
| Milk-vetch, [unnamed] | Astragalus microcymbus | - | 6 | UR |
| Milk-vetch, [unnamed] | Astragalus minthorniae gracilior | - | 6 | RT |
| Milk-vetch, [unnamed] | Astragalus molybdenus | - | 6 | SC |
| Milk-vetch, [unnamed] | Astragalus monumentalis | - | 6 | RT |
| Milk-vetch, [unnamed] | Astragalus neglectus | - | 3 | SC |
| Milk-vetch, [unnamed] | Astragalus nidularius | - | 6 | RT |
| Milk-vetch, [unnamed] | Astragalus nyensis | - | 1 | RT |
| Milk-vetch, [unnamed] | Astragalus oniciformis | - | 1 | RT |
| Milk-vetch, [unnamed] | Astragalus oocalycis | - | 6 | RT |
| Milk-vetch, [unnamed] | Astragalus panamintensis | - | 1 | RT |
| Milk-vetch, [unnamed] | Astragalus pardalinus | - | 6 | RT |
| Milk-vetch, [unnamed] | Astragalus pauperculus | - | 1 | RT |
| Milk-vetch, [unnamed] | Astragalus paysonii | - | 1 | SC |
| Milk-vetch, [unnamed] | Astragalus peckii | - | 1 | SC |
| Milk-vetch, [unnamed] | Astragalus porrectus | - | 1 | RT |
| Milk-vetch, [unnamed] | Astragalus preussii cutleri | - | 6 | SC |
| Milk-vetch, [unnamed] | Astragalus proimanthus | - | 6 | UR |
| Milk-vetch, [unnamed] | Astragalus proximus | - | 6 | SC |
| Milk-vetch, [unnamed] | Astragalus pterocarpus | - | 1 | RT |
| Milk-vetch, [unnamed] | Astragalus puniceus gertrudis | - | 2 | RT |
| Milk-vetch, [unnamed] | Astragalus purshii ophiogenes | - | 1 | RT |
| Milk-vetch, [unnamed] | Astragalus sabulosus | - | 6 | UR |
| Milk-vetch, [unnamed] | Astragalus scaphoides | - | 6 | RT |
| Milk-vetch, [unnamed] | Astragalus serenoi sordescens | - | 1 | RT |
| Milk-vetch, [unnamed] | Astragalus serpens | - | 6 | SC |
| Milk-vetch, [unnamed] | Astragalus shultziorum | - | 6 | RT |
| Milk-vetch, [unnamed] | Astragalus siliceus | - | 2 | RT |
| Milk-vetch, [unnamed] | Astragalus subvestitus | - | 1 | RT |
| Milk-vetch, [unnamed] | Astragalus tegetarioides | - | 1 | SC |
| Milk-vetch, [unnamed] | Astragalus tennesseensis | - | 4 | RT |
| Milk-vetch, [unnamed] | Astragalus titanophilus | - | 2 | RT |
| Milk-vetch, [unnamed] | Astragalus toquimanus | - | 1 | RT |
| Milk-vetch, [unnamed] | Astragalus troglodytus | - | 2 | RT |
| Milk-vetch, [unnamed] | Astragalus tweedyi | - | 1 | RT |
| Milk-vetch, [unnamed] | Astragalus tyghensis | - | 1 | SC |
| Milk-vetch, [unnamed] | Astragalus uncialis | - | 1 | SC |
| Milk-vetch, [unnamed] | Astragalus wittmannii | - | 2 | RT |
| Milk-vetch, [unnamed] | Astragalus woodruffii | - | 6 | RT |
| Milkpea, Small's | Galactia smallii | - | 4 | E |
| Milkpea, [unnamed] | Galactia pinetorum | - | 4 | SC |
| Milkvetch, Goose Creek | Astragalus anserinus | - | 6 | C |
| Milkvine, plateau | Matelea edwardsensis | - | 2 | RT |
| Milkvine, Texas | Matelea texensis | - | 2 | SC |
| Milkweed, Cutler | Asclepias cutleri | - | 2 | RT |
| Milkweed, Eastwood's | Asclepias eastwoodiana | - | 1 | SC |
| Milkweed, Mead's | Asclepias meadii | - | 3 | T |
| Milkweed, Ruth | Asclepias ruthiae | - | 6 | RT |
| Milkweed, San Juan | Asclepias sanjuanensis | - | 2 | RT |
| Milkweed, Welsh's | Asclepias welshii | - | 6 | T |
| Milkweed, [unnamed] | Asclepias prostrata | - | 2 | SC |
| Milkweed, [unnamed] | Asclepias uncialis | - | 6 | SC |
| Milkweed, [unnamed] | Asclepias viridula | - | 4 | SC |
| Milkwort, Fish's | Polygala cornuta var. fishiae | - | 8 | SC |
| Milkwort, Maravillas | Polygala maravillasensis | - | 2 | SC |
| Milkwort, Mescalero | Polygala rimulicola mescalerorum | - | 2 | SC |
| Millerbird, Nihoa (old world warbler) | Acrocephalus familiaris kingi | - | 1 | E |
| millipede, (Speodesmus) | speodesmus | - | 6 | SC |
| Millipede, [unnamed] | Toltecus chihuanus | - | 2 | SC |
| Mink, Everglades | Mustela vison evergladensis | - | 4 | RT |
| Mink, Florida | Mustela vison lutensis | - | 4 | RT |
| Minnow, cheat | Rhinichthys bowersi | - | 5 | SC |
| Minnow, Devils River | Dionda diaboli | - | 2 | T |
| Minnow, Kanawha | Phenacobius teretulus | - | 5 | SC |
| Minnow, loach | Tiaroga cobitis | - | 2 | T |
| Minnow, Plains | Hybognathus placitus | - | 6 | SC |
| Minnow, Rio Grande silvery | Hybognathus amarus | Entire, except where listed as an experimental population | 2 | E |
| Minnow, Rio Grande silvery | Hybognathus amarus | Rio Grande, from Little Box Canyon (approximately 10.4 river miles downstream of Fort Quitman, TX) to Amistad Dam; and on the Pecos River, from its confluence with Independence Creek to its confluence with the Rio Grande. | 2 | EXPN |
| Minnow, western silvery | Hybognathus argyritis | - | 6 | SC |
| Mint, Garrett's | Dicerandra christmanii | - | 4 | E |
| Mint, Lakela's | Dicerandra immaculata | - | 4 | E |
| Mint, longspurred | Dicerandra cornutissima | - | 4 | E |
| Mint, scrub | Dicerandra frutescens | - | 4 | E |
| Mint, [unnamed] | Dicerandra odoratissima | - | 4 | RT |
| Mint, [unnamed] | Dicerandra radfordiana | - | 4 | SC |
| Minute moss beetle, animas | Limnebius aridus | - | 2 | SC |
| Minute moss beetle, Maureen's gymnocthebius | Gymnocthebius maureenae | - | 4 | SC |
| Minute moss beetle, Maureen's hydraenan | Hydraena maureenae | - | 5 | SC |
| Minute moss beetle, Putnam | Ochthebius putnamensis | - | 3 | SC |
| Minute moss beetle, Texas | Limnebius texanus | - | 2 | SC |
| Minute moss beetle, Utah | Limnebius utahensis | - | 6 | SC |
| Minute moss beetle, Wilbur Springs | Ochthebius reticulus | - | 1 | SC |
| Minute moss beetle, wing-shoulder | Ochthebius crassalus | - | 1 | SC |
| Mission-bells, Diamond Lake | Fritillaria adamantina | - | 1 | RT |
| Mnium, Carolina | Mnium carolinianum | - | 4 | SC |
| Moccasinshell, Alabama | Medionidus acutissimus | - | 4 | T |
| Moccasinshell, Coosa | Medionidus parvulus | - | 4 | E |
| Moccasinshell, Gulf | Medionidus penicillatus | - | 4 | E |
| Moccasinshell, Ochlockonee | Medionidus simpsonianus | - | 4 | E |
| Moccasinshell, Suwanee | Medionidus walkeri | - | 4 | SC |
| Mock orange, canyon | Philadelphus ernestii | - | 2 | SC |
| Mockingbird, Socorro | Mimus graysoni | - | NA | E |
| Mold beetle, Magazine Mountain | Arianops sandersoni | - | 4 | SC |
| Mole cricket, prairie | Gryllotalpa major | - | 3 | SC |
| Mole, Alameda Island | Scapanus latimanus parvus | - | 1 | SC |
| Mole, Anastasia Island | Scalopus aquaticus anastasae | - | 4 | RT |
| Mole, Englewood | Scalopus aquaticus bassi | - | 4 | SC |
| Mole, Presidio | Scalopus aquaticus texanus | - | 2 | SC |
| Mole, star-nosed | Condylura cristata parva | - | 4 | RT |
| Monarch, Marquesan | Pomarea mendozae mira | - | Foreign | UR |
| Monarch, Tinian (old world flycatcher) | Monarcha takatsukasae | - | 1 | DM |
| Monarch, Truk | Metabolus rugensis | - | 1 | RT |
| Monardella, crisp | Monardella crispa | - | 1 | SC |
| Monardella, Feather River | Monardella stebbinsii | - | 1 | RT |
| Monardella, flax-like | Monardella linoides oblonga | - | 1 | SC |
| Monardella, Hall's | Monardella macrantha hallii | - | 1 | RT |
| Monardella, Merced | Monardella leucocephala | - | 1 | SC |
| Monardella, Palmer's | Monardella palmeri | - | 1 | RT |
| Monardella, Pringle | Monardella pringlei | - | 1 | SC |
| Monardella, Robison's | Monardella robisonii | - | 1 | SC |
| monardella, Robust | monardella villosa ssp. globosa | - | 6 | SC |
| Monardella, rock | Monardella viridis saxicola | - | 1 | RT |
| Monardella, San Antonio Hills | Monardella antonina | - | 1 | RT |
| Monardella, San Benito | Monardella benitensis | - | 1 | RT |
| Monardella, San Felipe | Monardella nana leptosiphon | - | 1 | SC |
| Monardella, San Luis Obispo | Monardella fructescens | - | 1 | SC |
| Monardella, Siskiyou | Monardella purpurea | - | 1 | RT |
| Monardella, Stone Corral Canyon | Monardella scelerata | - | 1 | RT |
| Monardella, veiny | Monardella douglasii venosa | - | 1 | SC |
| Monardella, willowy | Monardella linoides ssp. viminea | - | 8 | E |
| Monitor, desert | Varanus griseus | - | Foreign | E |
| Monitor, Indian (=Bengal) | Varanus bengalensis | - | Foreign | E |
| Monitor, Komodo Island | Varanus komodoensis | - | Foreign | E |
| Monitor, yellow | Varanus flavescens | - | Foreign | E |
| Monkey, black colobus | Colobus satanas | - | Foreign | E |
| Monkey, black howler | Alouatta pigra | - | Foreign | T |
| Monkey, Diana | Cercopithecus diana | - | Foreign | E |
| Monkey, Guizhou snub-nosed | Rhinopithecus brelichi | - | Foreign | E |
| Monkey, L'hoest's | Cercopithecus lhoesti | - | Foreign | E |
| Monkey, mantled howler | Alouatta palliata | - | Foreign | E |
| Monkey, Preuss' red colobus | Procolobus (=Colobus) preussi (=badius p.) | - | Foreign | E |
| Monkey, proboscis | Nasalis larvatus | - | Foreign | E |
| Monkey, red-backed squirrel | Saimiri oerstedii | - | Foreign | E |
| Monkey, red-bellied | Cercopithecus erythrogaster | - | Foreign | E |
| Monkey, red-eared nose-spotted | Cercopithecus erythrotis | - | Foreign | E |
| Monkey, Sichuan snub-nosed | Rhinopithecus roxellana | - | Foreign | E |
| Monkey, spider | Ateles geoffroyi frontatus | - | Foreign | E |
| Monkey, spider | Ateles geoffroyl panamensis | - | Foreign | E |
| Monkey, Tana River red colobus | Procolobus (=Colobus) rufomitratus (=badius r.) | - | Foreign | E |
| Monkey, Tonkin snub-nosed | Rhinopithecus avunculus | - | Foreign | E |
| Monkey, woolly spider | Brachyteles arachnoides | - | Foreign | E |
| Monkey, yellow-tailed woolly | Lagothrix flavicauda | - | Foreign | E |
| Monkey, Yunnan snub-nosed | Rhinopithecus bieti | - | Foreign | E |
| Monkey, Zanzibar red colobus | Procolobus (=Colobus) pennantii (=kirki) kirki | - | Foreign | E |
| Monkey-flower, Egg Lake | Mimulus pygmaeus | - | 1 | SC |
| Monkey-flower, Hetch Hetchy | Mimulus filicaulis | - | 1 | SC |
| Monkey-flower, Kelso Creek | Mimulus shevockii | - | 1 | RT |
| Monkey-flower, Michigan | Mimulus glabratus var. michiganensis | - | 3 | E |
| Monkey-flower, Mojave | Mimulus mohavensis | - | 1 | SC |
| Monkey-flower, purple | Mimulus purpureus purpureus | - | 1 | SC |
| Monkey-flower, San Bernardino Mountains | Mimulus exiguus | - | 1 | SC |
| Monkey-flower, Santa Catalina | Mimulus traskiae | - | 1 | SC |
| Monkey-flower, Santa Cruz Island | Mimulus brandegei | - | 1 | SC |
| Monkey-flower, square-stemmed | Mimulus ringens colpophilus | - | 5 | SC |
| Monkey-flower, stalk-leaved | Mimulus patulus | - | 1 | SC |
| Monkey-flower, Washington | Mimulus washingtonensis washingtonensis | - | 1 | SC |
| Monkey-flower, Weber | Mimulus gemmiparus | - | 6 | SC |
| Monkey-flower, Whipple's | Mimulus whipplei | - | 1 | SC |
| Monkeyface, Appalachian (pearlymussel) | Quadrula sparsa | - | 5 | E |
| Monkeyface, Appalachian (pearlymussel) | Quadrula sparsa | USA (TN - specified portions of the French Broad and Holston Rivers; see 17.85(b)(1)) | 4 | EXPN |
| Monkeyface, Cumberland (pearlymussel) | Quadrula intermedia | U.S.A. (AL;The free-flowing reach of the Tennessee R. from the base of Wilson Dam downstream to the backwaters of Pickwick Reservoir [about 12 RM (19 km)] and the lower 5 RM [8 km] of all tributaries to this reach in Colbert and Lauderdale Cos., see 17.85(a)) | 4 | EXPN |
| Monkeyface, Cumberland (pearlymussel) | Quadrula intermedia | Entire Range; Except where listed as Experimental Populations | 4 | E |
| Monkeyface, Cumberland (pearlymussel) | Quadrula intermedia | U.S.A. (TN - specified portions of the French Broad and Holston Rivers; see 17.85(b)(1)) | 4 | EXPN |
| Monkeyflower, bank | Mimulus clivicola | - | 1 | RT |
| Monkeyflower, calico | Mimulus pictus | - | 1 | RT |
| Monkeyflower, Cleveland's bush | Diplacus clevelandii | - | 8 | SC |
| Monkeyflower, Death Valley | Mimulus rupicola | - | 1 | RT |
| Monkeyflower, Kaweah | Mimulus norrisii | - | 1 | RT |
| monkeyflower, Palomar | mimulus diffusus | - | 6 | SC |
| Monkeyflower, [unnamed] | Mimulus guttatus arenicola | - | 1 | RT |
| Monkshood, northern wild | Aconitum noveboracense | - | 3 | T |
| Montia, Howell's | Montia howellii | - | 1 | SC |
| Moonwort, Prairie | Botrychium gallicomontanum | - | 3 | SC |
| Moonwort, slender | Botrychium lineare | - | 1 | RT |
| Moonwort, Stalked | Botrychium pedunculosum | - | 1 | SC |
| Moonwort, Trianglelobe | Botrychium ascendens | - | 1 | SC |
| Moorhen, Hawaiian common | Gallinula chloropus sandvicensis | - | 1 | E |
| Moorhen, Mariana common | Gallinula chloropus guami | - | 1 | E |
| Morning-glory, Butte County | Calystegia atriplicifolia buttensis | - | 1 | SC |
| Morning-glory, Cambria | Calystegia subacaulis episcopalis | - | 1 | SC |
| Morning-glory, island | Calystegia macrostegia amplissima | - | 1 | SC |
| Morning-glory, Krug's white | Ipomoea krugii | - | 4 | SC |
| Morning-glory, Lemmon's | Ipomoea tenuiloba lemmonii | - | 2 | RT |
| Morning-glory, Mt. Saint Helena | Calystegia collina oxyphylla | - | 1 | SC |
| Morning-glory, Peirson's | Calystegia peirsonii | - | 1 | SC |
| Morning-glory, Pickering's | Stylisma pickeringii | - | 5 | SC |
| Morning-glory, small-flowered | Convolvulus equitans | - | 8 | SC |
| Morning-glory, South Coast Range | Calystegia collina venusta | - | 1 | SC |
| Morning-glory, Stebbins' | Calystegia stebbinsii | - | 8 | E |
| Morning-glory, [unnamed] | Ipomoea egregia | - | 2 | RT |
| moss Cardot's campylium | Campylium cardotii | - | 6 | SC |
| moss Kansas aschisma | Aschisma kansanum | - | 6 | SC |
| Moss, American dry rock | Grimmia americana | - | 8 | SC |
| moss, Dicranoweisia | dicranoweisia crispula | - | 6 | SC |
| Moss, gorge | Bryocrumia vivicolor | - | 4 | SC |
| Moss, highlands | Schlotheimia lancifolia | - | 4 | SC |
| moss, Menzies' anacolia | anacolia menziesii | - | 6 | SC |
| Moss, Mt. Leconte | Leptothymenium sharpii | - | 4 | SC |
| moss, Whipple's claopodium | claopodium whippleanum | - | 6 | SC |
| Moth fly, sugarfoot | Nemopalpus nearcticus | - | 4 | SC |
| Moth, 'Poko' noctuid | Agrotis crinigera | - | 1 | RT |
| Moth, Blackburn's sphinx | Manduca blackburni | - | 1 | E |
| Moth, blue glyphodes | Glyphodes cyanomichla | - | 1 | SC |
| Moth, chestnut clearwing | Synanthedon castaneae | - | 4 | RT |
| Moth, confused helicoverpan noctuid | Helicoverpa confusa | - | 1 | RT |
| Moth, decodon borer | Papaipema sulphurata | - | 5 | SC |
| Moth, fabulous green sphinx | Tinostoma smaragditis | - | 1 | RT |
| Moth, flypoison borer | Papaipema sp. | - | 5 | SC |
| Moth, Ford's sand dune | Psammobotys fordi | - | 1 | SC |
| Moth, Fullaway's banana omoides | Omoides fullawayi | - | 1 | SC |
| Moth, Giffard's `ohe omoides | Omoides giffardi | - | 1 | SC |
| Moth, green glyphodes | Glyphodes exaula | - | 1 | SC |
| Moth, Haleakala flightless thyrocopa | Thyrocopa apatela | - | 1 | SC |
| Moth, Hawaiian lo`ulu omoides | Omoides pritchardii | - | 1 | SC |
| Moth, Henne's eucosman | Eucosma hennei | - | 1 | SC |
| Moth, Hilo hypenan noctuid | Hypena newelli | - | 1 | RT |
| Moth, Kaholuamano noctuid | Hypena senicula | - | 1 | RT |
| Moth, Kauai naenae philodoria | Philodoria naenaeiella | - | 1 | SC |
| Moth, Kern primrose sphinx | Euproserpinus euterpe | - | 8 | T |
| Moth, Kerr's agrotis noctuid | Agrotis kerri | - | 1 | RT |
| Moth, Kilauea pa`iniu omoides | Omoides iridias | - | 1 | SC |
| Moth, Kohala Mountain sedge omoides | Omoides anastreptoides | - | 1 | SC |
| Moth, Laysan agrotis noctuid | Agrotis laysanensis | - | 1 | RT |
| Moth, Laysan dropseed noctuid | Hypena laysanensis | - | 1 | RT |
| Moth, Laysan hedyleptan | Hedylepta laysanensis | - | 1 | RT |
| Moth, Lemmer's pinnion | Lithophane lemmeri | - | 5 | RT |
| Moth, Lora Aborn's | Lorita abornana | - | 1 | RT |
| Moth, lovegrass noctuid | Hypena plagiota | - | 1 | RT |
| Moth, marbled underwing | Catocala marmorata | - | 4 | RT |
| Moth, Maui banana omoides | Omoides musicola | - | 1 | SC |
| Moth, Meyrick's banana omoides | Omoides meyricki | - | 1 | SC |
| Moth, Midway agrotis noctuid | Agrotis fasciata | - | 1 | RT |
| Moth, minute helicoverpan noctuid | Helicoverpa minuta | - | 1 | RT |
| Moth, Molokai sedge omoides | Omoides anastrepta | - | 1 | SC |
| Moth, Oahu aulu thyrocopa | Thyrocopa sapindiella | - | 1 | SC |
| Moth, Oahu capper | Plutella capparidis | - | 1 | SC |
| Moth, Oahu hesperonmannia philodoria | Philodoria sp. | - | 1 | SC |
| Moth, Oahu swamp hedyleptan | Hedylepta epicentra | - | 1 | RT |
| Moth, Okefenokee zale | Zale perculta | - | 4 | SC |
| Moth, Ola`a banana omoides | Omoides euryprora | - | 1 | SC |
| Moth, Oso Flaco flightless | Areniscythris brachypteris | - | 1 | SC |
| Moth, Procellaris agrotis noctuid | Agrotis procellaris | - | 1 | RT |
| Moth, rattlesnake-master borer | Papaipema eryngii | - | 3 | SC |
| Moth, San Francisco tree lupine | Grapholita edwardsiana | - | 1 | RT |
| Moth, telegraphic hedyleptan | Hedylepta telegrapha | - | 1 | RT |
| Moth, `Ohe omoides | Omoides asaphombra | - | 1 | SC |
| Moth, `Ohenaupaka oeobian | Oeobia dryadopa | - | 1 | SC |
| Mountain balm, Indian Knob | Eriodictyon altissimum | - | 8 | E |
| Mountain beaver | Aplodontia rufa californica | - | 1 | SC |
| Mountain beaver, Point Arena | Aplodontia rufa nigra | - | 8 | E |
| Mountain beaver, Point Reyes | Aplodontia rufa phaea | - | 1 | SC |
| Mountain lion, California | Felis concolor californica | - | 1 | RT |
| Mountain parsley, purple | Oreonana purpurascens | - | 1 | RT |
| Mountain-mahogany, Catalina Island | Cercocarpus traskiae | - | 8 | E |
| Mountain-mint, [unnamed] | Pycnanthemum monotrichum | - | 5 | RT |
| mountainmint, Torrey's | Pycnanthemum torrei | - | 4 | SC |
| Mountainsnail Alpine | Oreohelix alpina | - | 6 | SC |
| Mountainsnail Bitterroot | Oreohelix amariradix | - | 6 | RT |
| Mountainsnail Brian Head | Oreohelix parawanensis | - | 6 | SC |
| Mountainsnail Carinate | Oreohelix elrodi | - | 6 | SC |
| Mountainsnail Eureka | Oreohelix eurekensis | - | 6 | SC |
| Mountainsnail Keeled | Oreohelix carinifera | - | 6 | RT |
| Mountainsnail Mill Creek | Oreohelix howardi | - | 6 | SC |
| Mountainsnail Pallid | Oreohelix hendersoni | - | 6 | SC |
| Mountainsnail Pygmy | Oreohelix pygmaea | - | 6 | SC |
| Mountainsnail, Berry's | Oreohelix strigosa berryi | - | 6 | SC |
| Mountainsnail, boulder pile | Oreohelix jugalis | - | 1 | SC |
| Mountainsnail, Byrne Resort | Oreohelix spthirtyone | - | 6 | UR |
| Mountainsnail, Carinated rocky | Oreohelix strigosa goniogyra | - | 1 | SC |
| Mountainsnail, Catalina | Radiocentrum avalonensis | - | 1 | SC |
| mountainsnail, Chelan | Oreohelix sp | - | 1 | SU |
| Mountainsnail, Coalville | Oreohelix peripherica weberiana | - | 6 | RT |
| Mountainsnail, Cooper's rocky | Oreohelix strigosa cooperi | - | 6 | SU |
| Mountainsnail, Eureka | Oreohelix eurekensis eurekensis | - | 6 | SC |
| Mountainsnail, Florida | Oreohelix florida | - | 2 | SC |
| Mountainsnail, Idaho banded | Oreohelix idahoensis idahoensis | - | 1 | SC |
| Mountainsnail, Lava rock | Oreohelix waltoni | - | 1 | SC |
| Mountainsnail, Lyrate | Oreohelix haydeni haydeni | - | 6 | SC |
| Mountainsnail, Mineral Creek | Oreohelix pilsbryi | - | 2 | SC |
| Mountainsnail, Ogden | Oreohelix peripherica wasatchensis | - | 6 | RT |
| Mountainsnail, Pahasapa | Oreohelix strigosa ssp. | - | 6 | SC |
| Mountainsnail, Pinaleno | Oreohelix grahamensis | - | 2 | RT |
| Mountainsnail, Schell Creek | Oreohelix nevadensis | - | 1 | SC |
| Mountainsnail, Uinta | Oreohelix eurekensis uinta | - | 6 | UR |
| Mountainsnail, whorled | Oreohelix vortex | - | 1 | SC |
| Mountainsnail, Yavapai | Oreohelix yavapai | - | 6 | SC |
| Mountainsnail, [unnamed] | Oreohelix haydeni corugata | - | 6 | SC |
| Mountainsnail, [unnamed] | Oreohelix parowanensis | - | 6 | SC |
| Mouse, Alabama beach | Peromyscus polionotus ammobates | - | 4 | E |
| Mouse, Anacapa deer | Peromyscus maniculatus anacapae | entire | 8 | RT |
| Mouse, Anastasia Island beach | Peromyscus polionotus phasma | - | 4 | E |
| Mouse, Anastasia Island cotton | Peromyscus gossypinus anastasae | - | 4 | RT |
| Mouse, Australian native | Notomys aquilo | - | Foreign | E |
| Mouse, Australian native | Zyzomys pedunculatus | - | Foreign | E |
| Mouse, Black Mountain cactus | Peromyscus eremicus pullus | - | 2 | SC |
| Mouse, Black Mountain pocket | Perognathus intermedius nigrimontis | - | 2 | SC |
| Mouse, Chadwick Beach cotton | Peromyscus gossypinus restrictus | - | 4 | RT |
| Mouse, Chiricahua western harvest | Reithrodontomys megalotis arizonensis | - | 2 | SC |
| Mouse, Choctawhatchee beach | Peromyscus polionotus allophrys | - | 4 | E |
| Mouse, Coconino Arizona pocket | Perognathus amplus ammodytes | - | 2 | SC |
| Mouse, Desert Valley kangaroo | Microdipodops megacephalus albiventer | - | 1 | SC |
| Mouse, Dulzura California pocket | Perognathus californicus femoralis | - | 1 | SC |
| Mouse, Field's | Pseudomys fieldi | - | Foreign | E |
| Mouse, Fletcher dark kangaroo | Microdipodops megacephalus nasutus | - | 1 | SC |
| Mouse, Florida | Peromyscus floridanus | - | 4 | SC |
| Mouse, Gould's | Pseudomys gouldii | - | Foreign | E |
| Mouse, Jacumba little pocket | Perognathus longimembris internationalis | - | 1 | SC |
| Mouse, Key Largo cotton | Peromyscus gossypinus allapaticola | - | 4 | E |
| Mouse, Los Angeles little pocket | Perognathus longimembris brevinasus | - | 1 | SC |
| Mouse, Martha's Vineyard white-footed | Peromyscus leucopus fusus | - | 5 | RT |
| Mouse, Monomoy white-footed | Peromyscus leucopus ammodytes | - | 5 | SC |
| Mouse, New Holland | Pseudomys novaehollandiae | - | Foreign | E |
| Mouse, New Mexico meadow jumping | Zapus hudsonius luteus | - | 2 | C |
| mouse, Northwestern San Diego pocket | chaetodipus fallax | - | 1 | SC |
| Mouse, Northwestern San Diego pocket | Perognathus fallax fallax | - | 1 | SC |
| Mouse, Pacific pocket | Perognathus longimembris pacificus | - | 8 | E |
| Mouse, pallid oldfield beach | Peromyscus polionotus decoloratus | - | 4 | RT |
| Mouse, Pallid San Diego pocket | Perognathus fallax pallidus | - | 1 | SC |
| Mouse, Palm Springs little pocket | Perognathus longimembris bangsi | entire | 8 | SC |
| Mouse, Palo Duro | Peromyscus truei comanche | - | 2 | SC |
| Mouse, Perdido Key beach | Peromyscus polionotus trissyllepsis | - | 4 | E |
| Mouse, Pinacate cactus | Peromyscus eremicus papagensis | - | 2 | SC |
| Mouse, Point Reyes jumping | Zapus trinotatus orarius | - | 1 | SC |
| Mouse, Preble's meadow jumping | Zapus hudsonius preblei | U.S.A., north-central CO (that portion of Colorado west of 103 degrees 40 minutes West, north of 38 degrees 30 minutes North, and east of 105 degrees 50 minutes West). | 6 | T |
| Mouse, Pungo white-footed | Peromyscus leucopus easti | - | 5 | RT |
| Mouse, Salinas pocket | Perognathus inornatus psammophilus | - | 1 | SC |
| Mouse, salt marsh harvest | Reithrodontomys raviventris | - | 8 | E |
| Mouse, San Clemente deer | Peromyscus maniculatus clementis | - | 1 | SC |
| Mouse, San Joaquin pocket | Perognathus inornatus | - | 1 | SC |
| Mouse, San Joaquin pocket | Perognathus inornatus inornatus | - | 1 | RT |
| Mouse, Santa Cruz harvest | Reithrodontomys megalotis santacruzae | - | 1 | RT |
| Mouse, Santa Rosa beach | Peromyscus polionotus leucocephalus | - | 4 | SC |
| Mouse, Shark Bay | Pseudomys praeconis | - | Foreign | E |
| Mouse, Shortridge's | Pseudomys shortridgei | - | Foreign | E |
| Mouse, silky pocket | Perognathus flavus goodpasteri | - | 2 | SC |
| Mouse, smoky | Pseudomys fumeus | - | Foreign | E |
| Mouse, southeastern beach | Peromyscus polionotus niveiventris | - | 4 | T |
| Mouse, southern grasshopper | Onychomys torridus ramona | - | 1 | SC |
| Mouse, southern marsh harvest | Reithrodontomys megalotis limicola | - | 1 | RT |
| Mouse, St. Andrew beach | Peromyscus polionotus peninsularis | - | 4 | E |
| Mouse, Stansbury Island harvest | Reithrodontomys megalotis ravus | - | 6 | SC |
| Mouse, Tehachapi white-eared pocket | Perognathus alticola inexpectatus | - | 1 | SC |
| Mouse, Tulare grasshopper | Onychomys torridus tularensis | - | 1 | SC |
| Mouse, western | Pseudomys occidentalis | - | Foreign | E |
| Mouse, white-eared pocket | Perognathus alticola alticola | - | 1 | SC |
| Mouse, Wupatki Arizona pocket | Perognathus amplus cineris | - | 2 | SC |
| Mouse, Yavapai Arizona pocket | Perognathus amplus amplus | - | 2 | SC |
| Mousetail, little | Myosurus minimus apus | - | 1 | SC |
| mousetail, tiny | Myosurus minimus | - | 1 | SC |
| Mucket, Neosho | Lampsilis rafinesqueana | - | 4 | C |
| Mucket, orangenacre | Lampsilis perovalis | - | 4 | T |
| Mucket, pink (pearlymussel) | Lampsilis abrupta | - | 4 | E |
| Mucket, Salina | Disconaias salinasensis | - | 2 | SC |
| Mudalia, black | Elimia melanoides | - | 4 | C |
| Mudalia, black | Leptoxis melanoidus | - | 4 | SC |
| Mudalia, knob | Leptoxis minor | - | 4 | SC |
| Mudminnow, Olympic | Novumbra hubbsi | - | 1 | RT |
| Mudwort, Chiricahua | Limosella pubiflora | - | 2 | SC |
| muhly, California | Muhlenbergia californica | - | 1 | SC |
| Muhly, Torrey's | Muhlenbergia torreyana | - | 5 | RT |
| Muhly, villous | Muhlenbergia villosa | - | 2 | RT |
| Muhly, [unnamed] | Muhlenbergia curtisetosa | - | 3 | RT |
| Muilla, crowned | Muilla coronata | - | 1 | RT |
| Mule-ears, El Dorado | Wyethia reticulata | - | 1 | SC |
| Muntjac, Fea's | Muntiacus feae | - | Foreign | E |
| Munzothamnus, Blair's | Stephanomeria blairii | - | 1 | SC |
| Murrelet, Kittlitz's | Brachyramphus brevirostris | - | 7 | C |
| Murrelet, marbled | Brachyramphus marmoratus | U.S.A. (CA, OR, WA) | 1 | T |
| Murrelet, marbled | Brachyramphus marmoratus | Entire, except U.S.A. (CA, OR, WA) | 7 | SC |
| Murrelet, Xantus's | Synthliboramphus hypoleucus | - | 8 | C |
| Murta | Marlierea sintenisii | - | 4 | RT |
| Mushroom, Indian Creek | Gloeocantharellus purpurascens | - | 4 | RT |
| Muskrat, Pecos River | Ondatra zibethicus ripensis | - | 2 | SC |
| Muskrat, round-tailed | Neofiber alleni | - | 4 | SC |
| Mussel, Lefevre's pearly | Epioblasma lefevrei | - | 3 | RT |
| Mussel, oyster | Epioblasma capsaeformis | U.S.A. (AL;The free-flowing reach of the Tennessee R. from the base of Wilson Dam downstream to the backwaters of Pickwick Reservoir [about 12 RM (19 km)] and the lower 5 RM [8 km] of all tributaries to this reach in Colbert and Lauderdale Cos., see 17.85(a)) | 4 | EXPN |
| Mussel, oyster | Epioblasma capsaeformis | U.S.A. (TN - specified portions of the French Broad and Holston Rivers; see 17.85(b)(1)) | 4 | EXPN |
| Mussel, oyster | Epioblasma capsaeformis | Entire Range; Except where listed as Experimental Populations | 4 | E |
| Mussel, salamander | Simpsonaias ambigua | - | 5 | SC |
| Mussel, scaleshell | Leptodea leptodon | - | 3 | E |
| Mussel, sheepnose | Plethobasus cyphyus | - | 3 | C |
| Mussel, snuffbox | Epioblasma triquetra | - | 4 | SC |
| Mustard, Carter's | Warea carteri | - | 4 | E |
| Mustard, Penland alpine fen | Eutrema penlandii | - | 6 | T |
| Mustard, slender-petaled | Thelypodium stenopetalum | - | 8 | E |
| myotis, California | myotis californicus | - | 8 | SC |
| Myotis, cave | Myotis velifer | - | 2 | SC |
| Myotis, fringed | Myotis thysanodes | - | 6 | SC |
| Myotis, fringed-tailed | Myotis thysanodes pahasapensis | - | 6 | SC |
| myotis, Keen's | myotis keenii | - | 7 | SC |
| Myotis, long-eared | Myotis evotis | - | 6 | SC |
| Myotis, long-legged | Myotis volans | - | 6 | SC |
| Myotis, small-footed | Myotis ciliolabrum | - | 6 | SC |
| Myotis, southeastern | Myotis austroriparius | - | 4 | SC |
| Myotis, Yuma | Myotis yumanensis | - | 1 | SC |
| Naenae | Dubautia kalalauensis | - | 1 | E |
| Naenae | Dubautia kenwoodii | - | 1 | E |
| Naiad, Fish Lake | Najas caespitosa | - | 6 | SC |
| Nailwort, silvery | Paronychia virginica virginica | - | 5 | SC |
| Naio | Myoporum sandwicense stellatum | - | 1 | RT |
| nama, Nama | nama stenocarpum | - | 6 | SC |
| Nani wai`ale`ale | Viola kauaiensis var. wahiawaensis | - | 1 | E |
| Nanu | Gardenia mannii | - | 1 | E |
| Nanu | Gardenia remyi | - | 1 | C |
| Native-cat, eastern | Dasyurus viverrinus | - | Foreign | E |
| Naucorid bug (=Furnace Creek), Nevares Spring | Ambrysus funebris | - | 8 | C |
| Naucorid, Amargosa | Pelocoris shoshone amargosa | - | 1 | UR |
| Naucorid, Ash Meadows | Ambrysus amargosus | - | 8 | T |
| Naupaka, dwarf | Scaevola coriacea | - | 1 | E |
| Naupaka, Kilauea | Scaevola kilaueae | - | 1 | RT |
| Naupaka, mountain | Scaevola gaudichaudi | - | 1 | RT |
| navarretia, Adobe | navarretia nigelliformis ssp. nigelliformis | - | 6 | SC |
| Navarretia, few-flowered | Navarretia leucocephala ssp. pauciflora (=N. pauciflora) | - | 8 | E |
| Navarretia, many-flowered | Navarretia leucocephala ssp. plieantha | - | 8 | E |
| Navarretia, Piute Mountains | Navarretia setiloba | - | 1 | RT |
| Navarretia, spreading | Navarretia fossalis | - | 8 | T |
| Navarretia, yellow-bur | Navarretia prolifera lutea | - | 1 | RT |
| Na`ena`e | Dubautia arborea | - | 1 | SC |
| Na`ena`e | Dubautia herbstobatae | - | 1 | E |
| Na`ena`e | Dubautia imbricata imbricata | - | 1 | E |
| Na`ena`e | Dubautia knudsenii filiformis | - | 1 | SC |
| Na`ena`e | Dubautia latifolia | - | 1 | E |
| Na`ena`e | Dubautia microcephala | - | 1 | SC |
| Na`ena`e | Dubautia pauciflorula | - | 1 | E |
| Na`ena`e | Dubautia plantaginea magnifolia | - | 1 | E |
| Na`ena`e | Dubautia plantaginea ssp. humilis | - | 1 | E |
| Na`ena`e | Dubautia struthioloides | - | 1 | RT |
| Na`ena`e | Dubautia waialealae | - | 1 | E |
| Na`ena`e-pua-melemele | Dubautia laxa waianensis | - | 1 | RT |
| Needlegrass, hairy Lemmon's | Stipa lemmonii pubescens | - | 1 | RT |
| Needlegrass, nodding | Nassella cernua | - | 1 | UR |
| Nehe | Lipochaeta fauriei | - | 1 | E |
| Nehe | Lipochaeta integrifolia gracilis | - | 1 | RT |
| Nehe | Lipochaeta integrifolia major | - | 1 | RT |
| Nehe | Lipochaeta integrifolia megacephala | - | 1 | RT |
| Nehe | Lipochaeta kamolensis | - | 1 | E |
| Nehe | Lipochaeta lavarum longifolia | - | 1 | RT |
| Nehe | Lipochaeta lavarum salicifolia | - | 1 | RT |
| Nehe | Lipochaeta lavarum skottsbergii | - | 1 | RT |
| Nehe | Lipochaeta lobata lobata | - | 1 | RT |
| Nehe | Lipochaeta lobata var. leptophylla | - | 1 | E |
| Nehe | Lipochaeta micrantha | - | 1 | E |
| Nehe | Lipochaeta perdita | - | 1 | RT |
| Nehe | Lipochaeta populifolia | - | 1 | RT |
| Nehe | Lipochaeta profusa robustior | - | 1 | RT |
| Nehe | Lipochaeta subcordata membranacea | - | 1 | RT |
| Nehe | Lipochaeta succulenta succulenta | - | 1 | RT |
| Nehe | Lipochaeta tenuifolia | - | 1 | E |
| Nehe | Lipochaeta tenuis | - | 1 | SC |
| Nehe | Lipochaeta waimeaensis | - | 1 | E |
| Nehe kuhiwa | Phyllostegia mollis hochreutineri | - | 1 | RT |
| Nehe, Bryan's | Lipochaeta bryanii | - | 1 | RT |
| Nehe, flexuous | Lipochaeta flexuosa | - | 1 | RT |
| Nehe, many-flowered | Lipochaeta profusa profusa | - | 1 | RT |
| Nehe, Remy's | Lipochaeta remyi | - | 1 | RT |
| Nehe, Rock's | Lipochaeta rockii | - | 1 | RT |
| Nehe, small-leaved | Lipochaeta degeneri | - | 1 | SC |
| Nehe, [unnamed] | Lipochaeta alata alata | - | 1 | RT |
| Nekogigi (catfish) | Coreobagrus ichikawai | - | Foreign | E |
| Nemacladus, Twisselmann's | Nemacladus twisselmannii | - | 1 | SC |
| Nepticulid moth, American chestnut | Ectodemia castaneae | - | 5 | SC |
| Nepticulid moth, phleophagan chestnut | Ectodemia phleophaga | - | 5 | SC |
| Newt, black-spotted | Notophthalmus meridionalis | - | 2 | UR |
| newt, Coast range | taricha torosa ssp. torosa | - | 6 | SC |
| newt, Rough-skinned | taricha granulosa | - | 7 | SC |
| Newt, striped | Notophthalmus perstriatus | - | 4 | UR |
| Night-blooming cereus, desert | Cereus greggii greggii | - | 2 | SC |
| nighthawk, Lesser | chordeiles acutipennis | - | 7 | SC |
| Nightjar, Puerto Rican | Caprimulgus noctitherus | - | 4 | E |
| Nightshade, narrow-leaved | Solanum tenuilobatum | - | 1 | SC |
| Nightshade, [unnamed] | Solanum bahamense rugelii | - | 4 | RT |
| Nino de cota | Laplacea portoricensis | - | 4 | RT |
| Nioi | Eugenia koolauensis | - | 1 | E |
| Niterwort, Amargosa | Nitrophila mohavensis | - | 8 | E |
| No comment name | Elimia lachryma | - | 4 | SC |
| No comment name | phytolacca sandwicensis | - | 1 | SC |
| No comment name | Pleurobema athearni | - | 4 | SC |
| No common name | Abronia ammophila var. | - | 6 | SC |
| No common name | Abutilon eremitopetalum | - | 1 | E |
| No common name | Abutilon parishii | - | 2 | SC |
| No common name | Abutilon sandwicense | - | 1 | E |
| No common name | Abutilon virginianum | - | 4 | SC |
| No common name | acarospora clauzadeana | - | 2 | SU |
| No common name | Acarospora clauzadeana | - | 2 | SU |
| No common name | Achyranthes atollensis | - | 1 | RT |
| No common name | Achyranthes mutica | - | 1 | E |
| No common name | Achyranthes splendens splendens | - | 1 | RT |
| No common name | Adiantum vivesii | - | 4 | E |
| No common name | Aerva sericea | - | 1 | RT |
| No common name | afilia species | - | 2 | SU |
| No common name | Agalinis purpurea carteri | - | 4 | RT |
| No common name | agapema galbina | - | 2 | SU |
| No common name | Agastache cusickii | - | 1 | RT |
| No common name | agathon arizonicus | - | 2 | SU |
| No common name | Agave eggersiana | - | 4 | UR |
| No common name | Agave mckelveyana | - | 2 | RT |
| No common name | Agave murpheyi | - | 2 | SC |
| No common name | Agave schottii treleasei | - | 2 | SC |
| No common name | Agave toumeyana bella | - | 2 | RT |
| No common name | Agave utahensis kaibabensis | - | 2 | RT |
| No common name | agylla septentrionalis | - | 2 | SU |
| No common name | albiorix anophthalmus | - | 2 | SU |
| No common name | Aletes filifolius | - | 2 | RT |
| No common name | Aletes humilis | - | 6 | SC |
| No common name | alexicles aspersa | - | 2 | SU |
| No common name | Allionia cristata | - | 2 | RT |
| No common name | Allomyia hector | - | 6 | SC |
| No common name | Allowissadula holosericea | - | 2 | RT |
| No common name | Alsinidendron obovatum | - | 1 | E |
| No common name | Alsinidendron trinerve | - | 1 | E |
| No common name | Alsinidendron viscosum | - | 1 | E |
| No common name | Alsophila brooksii | - | 4 | RT |
| No common name | Amaranthus brownii | - | 1 | E |
| No common name | Ameletus edmundsi | - | 6 | SC |
| No common name | amergoniscus centalis | - | 2 | SU |
| No common name | amergoniscus gipsocolus | - | 2 | SU |
| No common name | Amorpha brachycarpa | - | 3 | RT |
| No common name | Amsonia fugatei | - | 2 | SC |
| No common name | Amsonia tabernaemontana gattingeri | - | 4 | SC |
| No common name | Angelica scabrida | - | 1 | SC |
| No common name | Angelica wheeleri | - | 6 | RT |
| No common name | Antennaria aromatica | - | 6 | RT |
| No common name | Antennaria soliceps | - | 1 | SC |
| No common name | Apacheria chiricahuensis | - | 2 | RT |
| No common name | apocheiridium reddelli | - | 2 | SU |
| No common name | apodemia chisosensis | - | 2 | SU |
| No common name | Aquilegia barnebyi | - | 6 | RT |
| No common name | Aquilegia caerulea daileyae | - | 6 | RT |
| No common name | Aquilegia desertorum | - | 2 | RT |
| No common name | Aquilegia saximontana | - | 6 | RT |
| No common name | Arabis missouriensis deamii | - | 3 | SC |
| No common name | Arabis suffrutescens horizontalis | - | 1 | SC |
| No common name | Arceuthobium apachense | - | 2 | RT |
| No common name | archeolarca welbourni | - | 2 | SU |
| No common name | Arenaria franklinii thompsonii | - | 1 | RT |
| No common name | Arenaria kingii rosea | - | 1 | SC |
| No common name | Arenaria stenomeres | - | 1 | RT |
| No common name | Argemone arizonica | - | 2 | SC |
| No common name | Argemone glauca inermis | - | 1 | RT |
| No common name | arida mattturneri | - | 2 | SU |
| No common name | Aristida chaseae | - | 4 | E |
| No common name | Armoracia lacustris | - | 3 | RT |
| No common name | Arnica amplexicaulis piperi | - | 1 | RT |
| No common name | Arnica chionopappa | - | 3 | SC |
| No common name | Arnica paniculata | - | 6 | RT |
| No common name | Arnica venosa | - | 1 | RT |
| No common name | Artemisia biennis diffusa | - | 6 | SC |
| No common name | Artemisia ludoviciana estesii | - | 1 | SC |
| No common name | Artemisia papposa | - | 1 | RT |
| No common name | Artemisia unalaskensis aleutica | - | 7 | RT |
| No common name | aspidoscelis arizonae | - | 2 | UR |
| No common name | Asplenium fragile var. insulare | - | 1 | E |
| No common name | Asplenium schizophyllum | - | 1 | SC |
| No common name | Aster kingii barnebyana | - | 6 | SC |
| No common name | Astragalus amphioxys musimonum | - | 1 | SC |
| No common name | Astragalus collinus laurentii | - | 1 | SC |
| No common name | Astragalus diaphanus diurnus | - | 1 | SC |
| No common name | Astragalus geyeri triquetrus | - | 1 | SC |
| No common name | Astragalus gilviflora purpureus | - | 6 | SC |
| No common name | Astragalus jejunus articulatus | - | 6 | SC |
| No common name | Astragalus lentiginosus ambiguus | - | 2 | SC |
| No common name | Astragalus lentiginosus antonius | - | 1 | SC |
| No common name | Astragalus limnocharis limnocharis | - | 6 | SC |
| No common name | Astragalus limnocharis tabulaeus | - | 6 | SC |
| No common name | Astragalus oophorus lonchocalyx | - | 1 | SC |
| No common name | Astragalus pulsiferae suksdorfii | - | 1 | SC |
| No common name | Astragalus subcinereus basalticus | - | 6 | SC |
| No common name | Astragalus vexilliflexus nubilus | - | 1 | SC |
| No common name | Astranthium robustum | - | 2 | RT |
| No common name | astylis species | - | 2 | SU |
| No common name | Athene cunicularia ssp. hypugaea | - | 1 | SC |
| No common name | Atriplex canescens gigantea | - | 6 | SC |
| No common name | Atriplex welshii | - | 6 | RT |
| No common name | Auerodendron pauciflorum | - | 4 | E |
| No common name | Aureolaria patula | - | 4 | SC |
| No common name | automeris patagoniensis | - | 2 | SU |
| No common name | Bahia bigelovii | - | 2 | RT |
| No common name | Balduina atropurpurea | - | 4 | SC |
| No common name | Balsamorhiza rosea | - | 1 | RT |
| No common name | Balsamorhiza sericea | - | 1 | RT |
| No common name | Baptisia calycosa calycosa | - | 4 | SC |
| No common name | Baptisia simplicifolia | - | 4 | SC |
| No common name | Basiphyllaea angustifolia | - | 4 | RT |
| No common name | Bazzania nudicaulis | - | 4 | SC |
| No common name | Besseya bullii | - | 3 | RT |
| No common name | Blancosoma scaturgo | - | 6 | SC |
| No common name | Bonamia menziesii | - | 1 | E |
| No common name | Bothriochloa exaristata | - | 2 | RT |
| No common name | Botrychium crenulatum | - | 1 | SC |
| No common name | Botrychium mormo | - | 3 | SC |
| No common name | Botrychium pallidum | - | 6 | SC |
| No common name | Botrychium paradoxum | - | 6 | SC |
| No common name | Brachycercus tuberculatus | - | 6 | SC |
| No common name | Brassia caudata | - | 4 | RT |
| No common name | Braya humilis leiocarpa | - | 3 | RT |
| No common name | Brickellia dentata | - | 2 | RT |
| No common name | Brickellia leptophylla | - | 2 | RT |
| No common name | Bromus texensis | - | 2 | RT |
| No common name | Brunfelsia portoricensis | - | 4 | SC |
| No common name | Cacalia diversifolia | - | 4 | RT |
| No common name | Cacalia rugelia | - | 4 | SC |
| No common name | Caecidotea metcalfi | - | 6 | SC |
| No common name | Caecidotea tridentata | - | 6 | SC |
| No common name | Caesalpinia drummondii | - | 2 | RT |
| No common name | Calamintha ashei | - | 4 | SC |
| No common name | Calamintha dentata | - | 4 | RT |
| No common name | Calliandra locoensis | - | 4 | RT |
| No common name | Calochortus nitidus | - | 1 | SC |
| No common name | Calochortus weedii vestus | - | 1 | SC |
| No common name | Calyptranthes estremerae | - | 4 | RT |
| No common name | Calyptranthes luquillensis | - | 4 | SC |
| No common name | Calyptranthes peduncularis | - | 4 | SC |
| No common name | Calyptranthes thomasiana | - | 4 | E |
| No common name | Calyptranthes triflorum | - | 4 | SC |
| No common name | Camassia cusickii | - | 1 | RT |
| No common name | Camassia howellii | - | 1 | SC |
| No common name | Camissonia atwoodi | - | 6 | SC |
| No common name | Campanula rotundifolia sacajaweana | - | 1 | RT |
| No common name | Capnia arapahoe | - | 6 | SC |
| No common name | Cardamine penduliflora | - | 1 | RT |
| No common name | carex mckittrickensis | - | 2 | SU |
| No common name | Carex wahuensis herbstii | - | 1 | SC |
| No common name | Cassia fasciculata macrosperma | - | 5 | SC |
| No common name | Castilleja annua | - | 7 | RT |
| No common name | Castilleja chrysantha | - | 1 | RT |
| No common name | Castilleja cruenta | - | 2 | RT |
| No common name | Castilleja fraterna | - | 1 | SC |
| No common name | Castilleja glandulifera | - | 1 | RT |
| No common name | Castilleja linoides | - | 1 | RT |
| No common name | Castilleja oresbia | - | 1 | RT |
| No common name | Castilleja parviflora olympica | - | 1 | RT |
| No common name | Castilleja rubida | - | 1 | SC |
| No common name | Castilleja xanthotricha | - | 1 | RT |
| No common name | catapyrenium granulosum | - | 2 | SU |
| No common name | Catesbaea melanocarpa | - | 4 | E |
| No common name | Ceanothus arboreus glaber | - | 1 | SC |
| No common name | centaurium blumbergianum | - | 2 | SU |
| No common name | Cephaloziella obtusilobula | - | 4 | SC |
| No common name | Cereus greggii transmontanus | - | 2 | RT |
| No common name | ceuthothrombium cavaticum | - | 2 | SU |
| No common name | Chaenactis cusickii | - | 1 | SC |
| No common name | Chaenactis evermannii | - | 1 | RT |
| No common name | Chaenactis nevii | - | 1 | RT |
| No common name | Chaenactis ramosa | - | 1 | RT |
| No common name | Chaenactis thompsonii | - | 1 | RT |
| No common name | Chaetopappa elegans | - | 2 | SC |
| No common name | Chamaechaenactis scaposa | - | 1 | RT |
| No common name | Chamaecrista glandulosa var. mirabilis | - | 4 | E |
| No common name | Chamaerhodos nuttallii keweenawensis | - | 3 | SC |
| No common name | Chamaesyce celastroides stokesii | - | 1 | RT |
| No common name | Chamaesyce cumulicola | - | 4 | SC |
| No common name | Chamaesyce halemanui | - | 1 | E |
| No common name | Chamaesyce multiformis multiformis | - | 1 | RT |
| No common name | Chamaesyce ocellata rattanii | - | 1 | RT |
| No common name | Chamaesyce porteriana porteriana | - | 4 | SC |
| No common name | Cheilolejeunea evansii | - | 4 | SC |
| No common name | cheiridium reyesi | - | 2 | SU |
| No common name | Cheirodendron helleri helleri | - | 1 | RT |
| No common name | Cheirodendron helleri microcarpum | - | 1 | RT |
| No common name | Cheirodendron helleri sodalium | - | 1 | RT |
| No common name | Chelone obliqua speciosa | - | 4 | RT |
| No common name | Chenopodium oahuense discospermum | - | 1 | RT |
| No common name | Chiloscyphus gemmiparus | - | 6 | SC |
| No common name | chitrella elliotti | - | 2 | SU |
| No common name | chitrella major | - | 2 | SU |
| No common name | chitrella welbourni | - | 2 | SU |
| No common name | chitrellina chiricahuae | - | 2 | SU |
| No common name | Chorizanthe polygonoides longispina | - | 1 | SC |
| No common name | Chrysophyllum eggersii | - | 4 | SC |
| No common name | Chrysosplenium iowense | - | 3 | SC |
| No common name | Chrysothamnus eremobius | - | 1 | SC |
| No common name | Chrysothamnus molestus | - | 2 | SC |
| No common name | Chrysothamnus nauseosus nanus | - | 1 | RT |
| No common name | Chrysothamnus nauseosus texensis | - | 2 | SC |
| No common name | Chrysothamnus nauseosus var.iridus | - | 6 | SC |
| No common name | Chrysothamnus parryi hinckleyi | - | 2 | SC |
| No common name | cicurina barri | - | 2 | SU |
| No common name | cicurina browni | - | 2 | SU |
| No common name | cicurina caverna | - | 2 | SU |
| No common name | cicurina coryelli | - | 2 | SU |
| No common name | cicurina ezelli | - | 2 | SU |
| No common name | cicurina gruta | - | 2 | SU |
| No common name | cicurina holsingeri | - | 2 | SU |
| No common name | cicurina machete | - | 2 | SU |
| No common name | cicurina mckenziei | - | 2 | SU |
| No common name | cicurina medina | - | 2 | SU |
| No common name | cicurina menardia | - | 2 | SU |
| No common name | cicurina obscura | - | 2 | SU |
| No common name | cicurina orellia | - | 2 | SU |
| No common name | cicurina pablo | - | 2 | SU |
| No common name | cicurina pastura | - | 2 | SU |
| No common name | cicurina patei | - | 2 | SU |
| No common name | cicurina porteri | - | 2 | SU |
| No common name | cicurina puentecilla | - | 2 | SU |
| No common name | cicurina rainesi | - | 2 | SU |
| No common name | cicurina reclusa | - | 2 | SU |
| No common name | cicurina reddelli | - | 2 | SU |
| No common name | cicurina reyesi | - | 2 | SU |
| No common name | cicurina russelli | - | 2 | SU |
| No common name | cicurina sansaba | - | 2 | SU |
| No common name | cicurina selecta | - | 2 | SU |
| No common name | cicurina serena | - | 2 | SU |
| No common name | cicurina sheari | - | 2 | SU |
| No common name | cicurina sprousei | - | 2 | SU |
| No common name | cicurina stowersi | - | 2 | SU |
| No common name | cicurina stowersi | - | 2 | SU |
| No common name | cicurina suttoni | - | 2 | SU |
| No common name | cicurina travisae | - | 2 | SU |
| No common name | cicurina ubicki | - | 2 | SU |
| No common name | cicurina uvalde | - | 2 | SU |
| No common name | cicurina venefica | - | 2 | SU |
| No common name | cicurina vibora | - | 2 | SU |
| No common name | cicurina watersi | - | 2 | SU |
| No common name | Cimicifuga laciniata | - | 1 | RT |
| No common name | Cimicifuga rubifolia | - | 4 | SC |
| No common name | cisthene conjuncta | - | 2 | SU |
| No common name | Cladrastis kentukea | - | 4 | RT |
| No common name | Claytonia lanceolata chrysantha | - | 1 | RT |
| No common name | Claytonia lanceolata flava | - | 1 | SC |
| No common name | Claytonia megarhiza nivalis | - | 1 | RT |
| No common name | Cleomella montrosae | - | 6 | RT |
| No common name | Clermontia hawaiiensis hawaiiensis | - | 1 | RT |
| No common name | Clermontia konaensis | - | 1 | RT |
| No common name | Clermontia loyana | - | 1 | RT |
| No common name | Clermontia multiflora | - | 1 | RT |
| No common name | Clermontia munroi | - | 1 | RT |
| No common name | Clusia flava | - | 4 | RT |
| No common name | Coccoloba rugosa | - | 4 | RT |
| No common name | Cocculus integer | - | 1 | RT |
| No common name | Cocculus lonchophyllus | - | 1 | RT |
| No common name | Cocculus virgatus | - | 1 | RT |
| No common name | Coccyzus americanus ssp. occidentalis | - | 1 | SC |
| No common name | Coelorachis tuberculosa | - | 4 | SC |
| No common name | Collinsia antonina | - | 1 | SC |
| No common name | Collomia renacta | - | 1 | SC |
| No common name | Conostegia hotteana | - | 4 | SC |
| No common name | Coprosma faurei lanaiensis | - | 1 | RT |
| No common name | Coprosma montana orbicularis | - | 1 | RT |
| No common name | Coprosma ochracea kaalae | - | 1 | RT |
| No common name | Coprosma pubens sessiliflora | - | 1 | RT |
| No common name | Coprosma serrata | - | 1 | RT |
| No common name | Cordia bellonis | - | 4 | E |
| No common name | Cordia rupicola | - | 4 | C |
| No common name | Cordia wagnerorum | - | 4 | SC |
| No common name | Coreopsis heterolepis | - | 4 | RT |
| No common name | Coreopsis latifolia | - | 4 | RT |
| No common name | Coreopsis pulchra | - | 4 | RT |
| No common name | Coreopsis tripteris subrhomboidea | - | 2 | RT |
| No common name | Corydalis aquae-gelidae | - | 1 | SC |
| No common name | Corydalis caseana brachycarpa | - | 6 | RT |
| No common name | Corydalis caseana hastata | - | 1 | RT |
| No common name | Coryphantha dasyacantha dasyacantha | - | 2 | SC |
| No common name | Coryphantha dasyacantha varicolor | - | 2 | RT |
| No common name | Coursetia axillaris | - | 2 | RT |
| No common name | Coursetia glabella | - | 2 | SC |
| No common name | Cranichis ricartii | - | 4 | E |
| No common name | Crataegus stenosepala | - | 2 | RT |
| No common name | Crataegus sutherlandensis | - | 2 | RT |
| No common name | Crataegus triflora | - | 4 | SC |
| No common name | Crossosoma parviflorum | - | 2 | RT |
| No common name | Croton elliottii | - | 4 | RT |
| No common name | Croton fishlockii | - | 4 | SC |
| No common name | Croton glandulosus simpsonii | - | 4 | RT |
| No common name | Croton impressus | - | 4 | RT |
| No common name | Croton nummulariifolius | - | 4 | RT |
| No common name | Cryptantha cinerea arenicola | - | 6 | SC |
| No common name | Cryptantha creutzfeldtii | - | 6 | SC |
| No common name | Cryptantha hypsophila | - | 1 | RT |
| No common name | Cryptantha interrupta | - | 1 | RT |
| No common name | Cryptantha mensana | - | 6 | RT |
| No common name | Cryptantha paradoxa | - | 2 | RT |
| No common name | Cryptantha rollinsii | - | 6 | SC |
| No common name | Cryptantha subcapitata | - | 6 | SC |
| No common name | Cryptantha thompsonii | - | 1 | RT |
| No common name | Cryptocarya oahuensis | - | 1 | RT |
| No common name | Ctenium floridanum | - | 4 | RT |
| No common name | Cucurbita texana | - | 2 | RT |
| No common name | Cuphea aspera | - | 4 | SC |
| No common name | Cyanea (=Rollandia) crispa | - | 1 | E |
| No common name | Cyanea angustifolia lanaiensis | - | 1 | RT |
| No common name | Cyanea angustifolia racemosa | - | 1 | RT |
| No common name | Cyanea arborea | - | 1 | RT |
| No common name | Cyanea aspleniifolia | - | 1 | RT |
| No common name | Cyanea chockii | - | 1 | RT |
| No common name | Cyanea comata | - | 1 | RT |
| No common name | Cyanea giffardii | - | 1 | RT |
| No common name | Cyanea grimesiana cylindrocalyx | - | 1 | RT |
| No common name | Cyanea linearifolia | - | 1 | RT |
| No common name | Cyanea pohaku | - | 1 | RT |
| No common name | Cyanea profuga | - | 1 | RT |
| No common name | Cyanea pycnocarpa | - | 1 | RT |
| No common name | Cyanea quercifolia | - | 1 | RT |
| No common name | Cyanea scabra | - | 1 | RT |
| No common name | Cyclosorus boydiae boydiae | - | 1 | RT |
| No common name | Cyclosorus boydiae kipahuluensis | - | 1 | RT |
| No common name | Cymophyllus fraseri | - | 4 | RT |
| No common name | Cymopterus basalticus | - | 1 | RT |
| No common name | Cymopterus beckii | - | 6 | SC |
| No common name | Cymopterus corrugatus | - | 1 | RT |
| No common name | Cymopterus davisii | - | 1 | SC |
| No common name | Cymopterus douglassii | - | 1 | SC |
| No common name | Cymopterus everetii | - | 6 | RT |
| No common name | Cymopterus goodrichii | - | 1 | SC |
| No common name | Cymopterus ibapensis | - | 1 | RT |
| No common name | Cymopterus megacephalus | - | 2 | SC |
| No common name | Cymopterus newberryi | - | 2 | RT |
| No common name | Cymopterus nivalis | - | 1 | RT |
| No common name | Cymopterus ripleyi saniculoides | - | 1 | SC |
| No common name | Cymopterus rosei | - | 6 | RT |
| No common name | Cynanchum monense | - | 4 | RT |
| No common name | Cynanchum wigginsii | - | 2 | SC |
| No common name | Cyperus cephalanthus | - | 4 | SC |
| No common name | Cyperus granitophilus | - | 4 | RT |
| No common name | cyprinella species | - | 2 | SU |
| No common name | cyprinodon eremus | - | 2 | SU |
| No common name | Cyrtandra alata | - | 1 | RT |
| No common name | Cyrtandra alnea | - | 1 | RT |
| No common name | Cyrtandra ambigua | - | 1 | RT |
| No common name | Cyrtandra axilliflora | - | 1 | RT |
| No common name | Cyrtandra basipartita | - | 1 | RT |
| No common name | Cyrtandra bryanii | - | 1 | RT |
| No common name | Cyrtandra carinata | - | 1 | RT |
| No common name | Cyrtandra caudatisepala | - | 1 | RT |
| No common name | Cyrtandra chartacea | - | 1 | RT |
| No common name | Cyrtandra christophersenii | - | 1 | RT |
| No common name | Cyrtandra collarifera | - | 1 | RT |
| No common name | Cyrtandra conradtii | - | 1 | RT |
| No common name | Cyrtandra cordifolia brevipilita | - | 1 | RT |
| No common name | Cyrtandra cordifolia gynoglabra | - | 1 | RT |
| No common name | Cyrtandra crassior | - | 1 | RT |
| No common name | Cyrtandra cupuliformis | - | 1 | RT |
| No common name | Cyrtandra ellipticifolia | - | 1 | RT |
| No common name | Cyrtandra elliptisepala | - | 1 | RT |
| No common name | Cyrtandra ferricolorata | - | 1 | RT |
| No common name | Cyrtandra ferruginosa | - | 1 | RT |
| No common name | Cyrtandra forbesii | - | 1 | RT |
| No common name | Cyrtandra fosbergii | - | 1 | RT |
| No common name | Cyrtandra garberi | - | 1 | RT |
| No common name | Cyrtandra georgiana | - | 1 | RT |
| No common name | Cyrtandra glauca | - | 1 | RT |
| No common name | Cyrtandra gracilis | - | 1 | RT |
| No common name | Cyrtandra grayana lanaiensis | - | 1 | RT |
| No common name | Cyrtandra grossecrenata | - | 1 | RT |
| No common name | Cyrtandra hawaiensis | - | 1 | RT |
| No common name | Cyrtandra hirsutula | - | 1 | RT |
| No common name | Cyrtandra honolulensis | - | 1 | RT |
| No common name | Cyrtandra hosakae | - | 1 | RT |
| No common name | Cyrtandra intonsa | - | 1 | RT |
| No common name | Cyrtandra intrapilosa | - | 1 | RT |
| No common name | Cyrtandra kaalae | - | 1 | RT |
| No common name | Cyrtandra kahanensis | - | 1 | RT |
| No common name | Cyrtandra kahukuensis | - | 1 | RT |
| No common name | Cyrtandra kaluanuiensis | - | 1 | RT |
| No common name | Cyrtandra kaneoheensis | - | 1 | RT |
| No common name | Cyrtandra kohalae | - | 1 | RT |
| No common name | Cyrtandra koolauensis | - | 1 | RT |
| No common name | Cyrtandra laevis | - | 1 | RT |
| No common name | Cyrtandra laxiflora | - | 1 | RT |
| No common name | Cyrtandra lessoniana angustifolia | - | 1 | RT |
| No common name | Cyrtandra lessoniana intrapubens | - | 1 | RT |
| No common name | Cyrtandra longifolia longifolia | - | 1 | RT |
| No common name | Cyrtandra longiloba | - | 1 | RT |
| No common name | Cyrtandra lysiosepala grayi | - | 1 | RT |
| No common name | Cyrtandra lysiosepala haleakalensis | - | 1 | RT |
| No common name | Cyrtandra lysiosepala lysiosepala | - | 1 | RT |
| No common name | Cyrtandra malacophylla malacophylla | - | 1 | RT |
| No common name | Cyrtandra mannii | - | 1 | RT |
| No common name | Cyrtandra niuensis | - | 1 | RT |
| No common name | Cyrtandra nubincolens | - | 1 | RT |
| No common name | Cyrtandra olivacea | - | 1 | RT |
| No common name | Cyrtandra olona | - | 1 | RT |
| No common name | Cyrtandra paloloensis | - | 1 | RT |
| No common name | Cyrtandra paludosa haupuensis | - | 1 | RT |
| No common name | Cyrtandra partita | - | 1 | RT |
| No common name | Cyrtandra pearsallii | - | 1 | RT |
| No common name | Cyrtandra piligyna | - | 1 | RT |
| No common name | Cyrtandra platyphylla hiloensis | - | 1 | RT |
| No common name | Cyrtandra plurifolia | - | 1 | RT |
| No common name | Cyrtandra pubens | - | 1 | RT |
| No common name | Cyrtandra ramosissima | - | 1 | RT |
| No common name | Cyrtandra rockii | - | 1 | RT |
| No common name | Cyrtandra scabrella | - | 1 | RT |
| No common name | Cyrtandra skottsbergii | - | 1 | RT |
| No common name | Cyrtandra subcordata | - | 1 | RT |
| No common name | Cyrtandra subintegra | - | 1 | RT |
| No common name | Cyrtandra ternata | - | 1 | RT |
| No common name | Cyrtandra triflora | - | 1 | RT |
| No common name | Cyrtandra turbiniformis | - | 1 | RT |
| No common name | Cyrtandra vaniota | - | 1 | RT |
| No common name | Cyrtandra villicalyx pubentigyna | - | 1 | RT |
| No common name | Cyrtandra villosa | - | 1 | RT |
| No common name | Cyrtandra villosiflora | - | 1 | RT |
| No common name | Cyrtandra waiolani | - | 1 | RT |
| No common name | Dalea gattingeri | - | 4 | RT |
| No common name | Daphnopsis hellerana | - | 4 | E |
| No common name | Dasynotus daubenmirei | - | 1 | RT |
| No common name | Delissea fallax | - | 1 | RT |
| No common name | Delissea laciniata | - | 1 | RT |
| No common name | Delissea lauliiana | - | 1 | RT |
| No common name | Delissea parviflora | - | 1 | RT |
| No common name | Delissea rhytidosperma | - | 1 | E |
| No common name | Delissea sinuata | - | 1 | RT |
| No common name | Delissea undulata | - | 1 | E |
| No common name | Dendrographa leucophaea | - | 1 | SC |
| No common name | Dentaria incisa | - | 4 | RT |
| No common name | Descurainia torulosa | - | 6 | SC |
| No common name | Dicliptera krugii | - | 4 | SC |
| No common name | Diellia falcata | - | 1 | E |
| No common name | Diellia mannii | - | 1 | E |
| No common name | Diellia pallida | - | 1 | E |
| No common name | Diellia unisora | - | 1 | E |
| No common name | Digitaria floridana | - | 4 | SC |
| No common name | Digitaria gracillima | - | 4 | SC |
| No common name | Diplazium molokaiense | - | 1 | E |
| No common name | Dissochondrus biflorus | - | 1 | RT |
| No common name | Ditaxis diversiflora | - | 1 | RT |
| No common name | Dodecatheon poeticum | - | 1 | RT |
| No common name | Dodonaea eriocarpa confertior | - | 1 | RT |
| No common name | Dodonaea eriocarpa costulata | - | 1 | RT |
| No common name | Dodonaea eriocarpa forbesii | - | 1 | RT |
| No common name | Dodonaea eriocarpa lanaiensis | - | 1 | RT |
| No common name | Dodonaea eriocarpa molokaiensis | - | 1 | RT |
| No common name | Dodonaea eriocarpa oblonga | - | 1 | RT |
| No common name | Dodonaea eriocarpa pallida | - | 1 | RT |
| No common name | Dodonaea eriocarpa skottsbergii | - | 1 | RT |
| No common name | Dodonaea eriocarpa varians | - | 1 | RT |
| No common name | Dodonaea sandwicensis latifolia | - | 1 | RT |
| No common name | Dodonaea sandwicensis simulans | - | 1 | RT |
| No common name | Dodonaea stenoptera fauriei | - | 1 | RT |
| No common name | Dodonaea stenoptera stenoptera | - | 1 | RT |
| No common name | Doryopteris angelica | - | 1 | E |
| No common name | Doryopteris takeuchii | - | 1 | C |
| No common name | Douglasia idahoensis | - | 1 | SC |
| No common name | Douglasia laevigata laevigata | - | 1 | RT |
| No common name | Douglasia nivalis nivalis | - | 1 | RT |
| No common name | Draba apiculata daviesiae | - | 6 | RT |
| No common name | Draba aprica | - | 4 | RT |
| No common name | Draba argyraea | - | 1 | RT |
| No common name | Draba arida | - | 1 | SC |
| No common name | Draba asprella asprella | - | 2 | RT |
| No common name | Draba asprella kaibabensis | - | 2 | RT |
| No common name | Draba asprella stelligera | - | 2 | RT |
| No common name | Draba jaegeri | - | 1 | SC |
| No common name | Draba kassii | - | 6 | SC |
| No common name | Draba lemmonii cyclomorpha | - | 1 | RT |
| No common name | Draba maguirei burkei | - | 6 | RT |
| No common name | Draba maguirei maguirei | - | 6 | RT |
| No common name | Draba mogollonica | - | 2 | RT |
| No common name | Draba murrayi | - | 7 | SC |
| No common name | Draba oreibata serpentina | - | 1 | SC |
| No common name | Draba paucifructa | - | 1 | SC |
| No common name | Draba pectinipila | - | 6 | SC |
| No common name | Draba ruaxes | - | 7 | RT |
| No common name | Draba smithii | - | 6 | SC |
| No common name | Draba sphaeroides cusickii | - | 1 | RT |
| No common name | Draba yukonensis | - | 7 | SC |
| No common name | Dracontium polyphyllum | - | 4 | SC |
| No common name | Dryopteris glabra var. pusilla | - | 1 | RT |
| No common name | Dryopteris takeuchii | - | 1 | SU |
| No common name | Dubautia hillebrandii | - | 1 | RT |
| No common name | Dubautia knudsenii degeneri | - | 1 | RT |
| No common name | Dubautia laevigata parvifolia | - | 1 | RT |
| No common name | Dubautia laxa blakei | - | 1 | RT |
| No common name | Dubautia lonchophylla | - | 1 | RT |
| No common name | Dubautia magnifolia | - | 1 | RT |
| No common name | Dubautia molokaiensis | - | 1 | RT |
| No common name | Dubautia montana robustior | - | 1 | RT |
| No common name | Dubautia plantaginea acridentata | - | 1 | RT |
| No common name | Dubautia plantaginea plantaginea | - | 1 | RT |
| No common name | Dubautia platyphylla leptophylla | - | 1 | RT |
| No common name | Dubautia reticulata | - | 1 | RT |
| No common name | Dubautia rockii | - | 1 | RT |
| No common name | Dubautia ternifolia | - | 1 | RT |
| No common name | Dubautia thyrsiflora cernua | - | 1 | RT |
| No common name | Dubautia thyrsiflora thyrsiflora | - | 1 | RT |
| No common name | Dudleya saxosa collomiae | - | 2 | RT |
| No common name | Dyschoriste crenulata | - | 2 | RT |
| No common name | echeandia texensis | - | 2 | SU |
| No common name | Echinocereus ledingii | - | 2 | RT |
| No common name | Echinodorus parvulus | - | 6 | SC |
| No common name | Echinomastus erectocentrus erectocentrus | - | 2 | SC |
| No common name | Echinomastus warnockii | - | 2 | RT |
| No common name | eidmannella bullata | - | 2 | SU |
| No common name | eidmannella delicata | - | 2 | SU |
| No common name | eidmannella nasuta | - | 2 | SU |
| No common name | eidmannella reclusa | - | 2 | SU |
| No common name | Elaphoglossum serpens | - | 4 | E |
| No common name | Eleocharis austrotexana | - | 2 | RT |
| No common name | Eleocharis wolfii | - | 3 | SC |
| No common name | Elymus svensonii | - | 4 | SC |
| No common name | Elytraria caroliniensis angustifolia | - | 4 | SC |
| No common name | Elytraria caroliniensis caroliniensis | - | 4 | RT |
| No common name | Embelia hillebrandii | - | 1 | RT |
| No common name | Encelia frutescens resinosa | - | 2 | RT |
| No common name | Encyclia kranzlinii | - | 4 | SC |
| No common name | Encyclia krugii | - | 4 | RT |
| No common name | Encyclia sintenisii | - | 4 | RT |
| No common name | Ephemerella apopsis | - | 6 | SC |
| No common name | Epidendrum brittonianum | - | 4 | RT |
| No common name | Epidendrum lacerum | - | 4 | RT |
| No common name | Eragrostis deflexa | - | 1 | RT |
| No common name | Eragrostis hosakai | - | 1 | SC |
| No common name | Eragrostis paupera | - | 1 | RT |
| No common name | Erigeron arenarioides | - | 6 | RT |
| No common name | Erigeron arizonicus | - | 2 | RT |
| No common name | Erigeron bigelovii | - | 2 | RT |
| No common name | Erigeron canaanii | - | 6 | SC |
| No common name | Erigeron carringtonae | - | 6 | SC |
| No common name | Erigeron chrysopsidis brevifolius | - | 1 | RT |
| No common name | Erigeron flettii | - | 1 | RT |
| No common name | Erigeron garrettii | - | 6 | RT |
| No common name | Erigeron hultenii | - | 7 | RT |
| No common name | Erigeron lackshewitz | - | 6 | SC |
| No common name | Erigeron leibergii | - | 1 | RT |
| No common name | Erigeron lobatus | - | 2 | RT |
| No common name | Erigeron maguirei harrisonii | - | 6 | SC |
| No common name | Erigeron muirii | - | 7 | RT |
| No common name | Erigeron ovinus | - | 1 | SC |
| No common name | Erigeron perglaber | - | 2 | RT |
| No common name | Erigeron piperanus | - | 1 | RT |
| No common name | Erigeron pringlei | - | 2 | RT |
| No common name | Erigeron pulchellus tolsteadii | - | 3 | SC |
| No common name | Erigeron salmonensis | - | 1 | SC |
| No common name | Erigeron sionis | - | 6 | SC |
| No common name | Erigeron sivinskii | - | 2 | SC |
| No common name | Erigeron uncialis conjugans | - | 1 | RT |
| No common name | Erigeron untermannii | - | 6 | SC |
| No common name | Erigeron wilkenii | - | 6 | SC |
| No common name | Erigeron zothecinus | - | 6 | RT |
| No common name | Eriochloa michauxii simpsonii | - | 4 | SC |
| No common name | Eriogonum allenii | - | 5 | RT |
| No common name | Eriogonum concinnum | - | 1 | RT |
| No common name | Eriogonum correllii | - | 2 | RT |
| No common name | Eriogonum densum | - | 2 | RT |
| No common name | Eriogonum grayi | - | 6 | RT |
| No common name | Eriogonum heermannii subracemosum | - | 2 | RT |
| No common name | Eriogonum lagopus | - | 6 | SC |
| No common name | Eriogonum latens | - | 1 | RT |
| No common name | Eriogonum lewisii | - | 1 | SC |
| No common name | Eriogonum lobbii robustum | - | 1 | SC |
| No common name | Eriogonum longifolium harperi | - | 4 | SC |
| No common name | Eriogonum natum | - | 6 | RT |
| No common name | Eriogonum novonudum | - | 1 | RT |
| No common name | Eriogonum nummulare | - | 6 | RT |
| No common name | Eriogonum ovalifolium caelestinum | - | 1 | RT |
| No common name | Eriogonum rubricaule | - | 1 | RT |
| No common name | Eriogonum scopulorum | - | 1 | RT |
| No common name | Eriogonum soredium | - | 6 | UR |
| No common name | eriogonum terrenatum | - | 2 | SU |
| No common name | Eriogonum thymoides | - | 1 | RT |
| No common name | Eriogonum tumulosum | - | 6 | RT |
| No common name | Eriogonum umbellatum hypoleium | - | 1 | RT |
| No common name | Eriogonum viridulum | - | 6 | RT |
| No common name | Eriogonum visheri | - | 6 | SC |
| No common name | Erithalis revoluta | - | 4 | SC |
| No common name | Errazurizia rotundata | - | 2 | RT |
| No common name | Erythronium cliftonii | - | 1 | RT |
| No common name | Erythronium elegans | - | 1 | SC |
| No common name | Erythronium grandiflorum nudipetalum | - | 1 | RT |
| No common name | Erythronium helenae | - | 1 | RT |
| No common name | Erythronium oregonum | - | 1 | RT |
| No common name | Eschscholzia multiflora twisselmannii | - | 1 | SC |
| No common name | Eugenia bellonis | - | 4 | SC |
| No common name | Eugenia margarettae | - | 4 | SC |
| No common name | Eugenia underwoodii | - | 4 | SC |
| No common name | Eugenia woodburyana | - | 4 | E |
| No common name | euhyparpax rosea | - | 2 | SU |
| No common name | Eupatorium borinquense | - | 4 | SC |
| No common name | Eupatorium luciae-brauniae | - | 4 | SC |
| No common name | Eupatorium oteroi | - | 4 | SC |
| No common name | Eupatorium saltuense | - | 4 | RT |
| No common name | Euphorbia austrina | - | 4 | RT |
| No common name | Euphorbia celastroides halawana | - | 1 | RT |
| No common name | Euphorbia celastroides haupuana | - | 1 | RT |
| No common name | Euphorbia celastroides humbertii | - | 1 | RT |
| No common name | Euphorbia celastroides kohalana | - | 1 | RT |
| No common name | Euphorbia celastroides nelsonii | - | 1 | RT |
| No common name | Euphorbia celastroides nematopoda | - | 1 | RT |
| No common name | Euphorbia celastroides saxicola | - | 1 | RT |
| No common name | Euphorbia celastroides waikoluensis | - | 1 | RT |
| No common name | Euphorbia degeneri molokaiensis | - | 1 | RT |
| No common name | Euphorbia discoidalis | - | 4 | RT |
| No common name | Euphorbia exserta | - | 4 | RT |
| No common name | Euphorbia innocua | - | 2 | RT |
| No common name | Euphorbia jejuna | - | 2 | RT |
| No common name | Euphorbia plummerae | - | 2 | SC |
| No common name | Euphorbia roemeriana | - | 2 | RT |
| No common name | Euphorbia strictior | - | 2 | RT |
| No common name | Eurhychium pringlei | - | 4 | SC |
| No common name | Eurya sandwicensis | - | 1 | SC |
| No common name | eurycea species | - | 2 | SU |
| No common name | eurycea species | - | 2 | SU |
| No common name | eurycea species | - | 2 | SU |
| No common name | eurycea specieseight | - | 2 | UR |
| No common name | eurycea speciesten | - | 2 | UR |
| No common name | Eurytaenia hinckleyi | - | 2 | RT |
| No common name | Exocarpos gaudichaudii | - | 1 | SC |
| No common name | Ferocactus eastwoodiae | - | 2 | RT |
| No common name | Festuca hallii | - | 6 | RT |
| No common name | Festuca hawaiiensis | - | 1 | C |
| No common name | Fimbristylis hawaiiensis | - | 1 | SC |
| No common name | Flaveria mcdougallii | - | 2 | RT |
| No common name | Flyriella parryi | - | 2 | RT |
| No common name | Forchhammeria polyandra | - | 4 | SC |
| No common name | Forestiera segregata pinetorum | - | 4 | SC |
| No common name | Frasera coloradensis | - | 6 | SC |
| No common name | Frasera idahoensis | - | 1 | RT |
| No common name | Frasera puberulenta | - | 1 | RT |
| No common name | Frasera tubulosa | - | 1 | RT |
| No common name | Gahnia lanaiensis | - | 1 | E |
| No common name | Galactia eggersii | - | 4 | SC |
| No common name | Galinsoga semicalva percalva | - | 2 | RT |
| No common name | Gardenia weissichii | - | 1 | RT |
| No common name | Gaura demareei | - | 4 | RT |
| No common name | Gentiana austromontana | - | 4 | RT |
| No common name | Gentianella propinqua aleutica | - | 7 | RT |
| No common name | Gentianella wislizenii | - | 2 | SC |
| No common name | Geocarpon minimum | - | 4 | T |
| No common name | geomys streckeri | - | 2 | SU |
| No common name | Gesneria pauciflora | - | 4 | T |
| No common name | Gilia mcvickerae | - | 6 | RT |
| No common name | Gilia nyensis | - | 1 | RT |
| No common name | Gilia pentstemonoides | - | 6 | RT |
| No common name | Gilia ripleyi | - | 1 | RT |
| No common name | Gilia tenuis | - | 6 | UR |
| No common name | Gnaphalium macounii | - | 3 | RT |
| No common name | Gonocalyx concolor | - | 4 | C |
| No common name | Gouania hillebrandii | - | 1 | E |
| No common name | Gouania meyenii | - | 1 | E |
| No common name | Gouania vitifolia | - | 1 | E |
| No common name | Gouldia st-johnii munroi | - | 1 | RT |
| No common name | Gouldia terminalis bobeoides | - | 1 | RT |
| No common name | Gouldia terminalis congesta | - | 1 | RT |
| No common name | Gouldia terminalis crassicaulis | - | 1 | RT |
| No common name | Gouldia terminalis degeneri | - | 1 | RT |
| No common name | Gouldia terminalis lanai | - | 1 | RT |
| No common name | Gouldia terminalis parvifolia | - | 1 | RT |
| No common name | Gouldia terminalis pseudodichotoma | - | 1 | RT |
| No common name | Gouldia terminalis pubescens | - | 1 | RT |
| No common name | Gouldia terminalis quadrangularis | - | 1 | RT |
| No common name | Gouldia terminalis rotundifolia | - | 1 | RT |
| No common name | Gouldia terminalis subcordata | - | 1 | RT |
| No common name | Graptopetalum bartramii | - | 2 | SC |
| No common name | Graptopetalum rusbyi | - | 2 | RT |
| No common name | Greenella discoidea | - | 2 | RT |
| No common name | Gunnera kaalensis | - | 1 | RT |
| No common name | Gunnera makahaensis | - | 1 | RT |
| No common name | Gutierrezia linoides | - | 2 | RT |
| No common name | Gutierrezia petradoria | - | 6 | RT |
| No common name | Gutierrezia sarothrae pomariensis | - | 6 | RT |
| No common name | Gymnocarpium heterosporum | - | 3 | RT |
| No common name | Gymnopogon floridanus | - | 4 | RT |
| No common name | Habenaria zothecina | - | 6 | SC |
| No common name | Hackelia hispida | - | 1 | RT |
| No common name | Halimolobos perplexa lemhiensis | - | 1 | RT |
| No common name | Halimolobos perplexa perplexa | - | 1 | RT |
| No common name | Haplopappus aberrans | - | 1 | RT |
| No common name | Haplopappus alpinus | - | 1 | SC |
| No common name | Haplopappus carthamoides subsquarrosus | - | 6 | SC |
| No common name | Haplopappus cervinus | - | 1 | RT |
| No common name | Haplopappus crispus | - | 6 | SC |
| No common name | Haplopappus graniticus | - | 1 | SC |
| No common name | Haplopappus hallii | - | 1 | RT |
| No common name | Haplopappus insecticruris | - | 1 | RT |
| No common name | Haplopappus liatriformis | - | 1 | SC |
| No common name | Haplopappus racemosus congestus | - | 1 | RT |
| No common name | Haplopappus scopulorum | - | 2 | RT |
| No common name | Haplopappus spinulosus laevis | - | 2 | RT |
| No common name | Haplopappus watsonii | - | 1 | RT |
| No common name | Haplopappus zionis | - | 6 | SC |
| No common name | Haplostachys bryanii | - | 1 | RT |
| No common name | Haplostachys linearifolia | - | 1 | RT |
| No common name | Haplostachys munroi | - | 1 | RT |
| No common name | Haplostachys truncata | - | 1 | RT |
| No common name | Hastingsia atropurpurea | - | 1 | SC |
| No common name | Hastingsia bracteosa | - | 1 | SC |
| No common name | Hazardia brickellioides | - | 1 | RT |
| No common name | Hechtia texensis | - | 2 | RT |
| No common name | Hedeoma dentatum | - | 2 | RT |
| No common name | Hedeoma molle | - | 2 | RT |
| No common name | Hedeoma nanum californicum | - | 1 | RT |
| No common name | Hedeoma pulcherrimum | - | 2 | RT |
| No common name | Hedyotis angusta angusta | - | 1 | RT |
| No common name | Hedyotis degeneri | - | 1 | E |
| No common name | Hedyotis elatior | - | 1 | SC |
| No common name | Hedyotis foliosa | - | 1 | RT |
| No common name | Hedyotis formosa | - | 1 | SC |
| No common name | Hedyotis glaucifolia helleri | - | 1 | RT |
| No common name | Hedyotis littoralis | - | 1 | SC |
| No common name | Hedyotis parvula | - | 1 | E |
| No common name | Hedyotis remyi nuttallii | - | 1 | RT |
| No common name | Hedyotis remyi plana | - | 1 | RT |
| No common name | Hedyotis schlechtendahliana nuttallii | - | 1 | RT |
| No common name | Hedyotis schlechtendahliana plana | - | 1 | RT |
| No common name | Hedyotis schlechtendahliana reticulata | - | 1 | RT |
| No common name | Hedyotis tryblium | - | 1 | SC |
| No common name | Hedysarum boreale gremiale | - | 6 | RT |
| No common name | Hedysarum occidentale canone | - | 6 | SC |
| No common name | Helenium arizonicum | - | 2 | RT |
| No common name | Helianthus carnosus | - | 4 | SC |
| No common name | Helianthus deserticola | - | 6 | RT |
| No common name | Helianthus glaucophyllus | - | 4 | RT |
| No common name | Helianthus laciniatus crenatus | - | 2 | RT |
| No common name | Helianthus praetermissus | - | 2 | RT |
| No common name | Helianthus smithii | - | 4 | RT |
| No common name | Heliotropium polyphyllum horizontale | - | 4 | RT |
| No common name | Hermidium alipes pallidum | - | 6 | RT |
| No common name | Herricka horrida | - | 6 | SC |
| No common name | Hesperocnide sandwicensis | - | 1 | RT |
| No common name | Hesperomannia arborescens | - | 1 | E |
| No common name | Hesperomannia arbuscula | - | 1 | E |
| No common name | Hesperomannia lydgatei | - | 1 | E |
| No common name | heterocampa amanda | - | 2 | SU |
| No common name | Heterodermia erinacea | - | 1 | SC |
| No common name | Heterotheca rutteri | - | 2 | SC |
| No common name | Heuchera missouriensis | - | 3 | RT |
| No common name | Heuchera villosa arkansana | - | 4 | RT |
| No common name | Hexastylis contracta | - | 4 | SC |
| No common name | Hibiscadelphus bombycinus | - | 1 | RT |
| No common name | Hibiscadelphus wilderanus | - | 1 | RT |
| No common name | Hibiscus waimeae waimeae | - | 1 | RT |
| No common name | Hieracium longiberbe | - | 1 | RT |
| No common name | Holocarpha virgata elongata | - | 1 | SC |
| No common name | holospira animasensis | - | 2 | SU |
| No common name | Hymenocallis latifolia | - | 4 | RT |
| No common name | Hymenopappus filifolius idahoensis | - | 1 | RT |
| No common name | Hymenoxys depressa | - | 6 | SC |
| No common name | Hymenoxys helenioides | - | 6 | RT |
| No common name | Hymenoxys lapidicola | - | 6 | RT |
| No common name | Hymenoxys quinquesquamata | - | 2 | RT |
| No common name | Hymenoxys subintegra | - | 2 | RT |
| No common name | Hymenoxys turneri | - | 2 | RT |
| No common name | Hypericum adpressum | - | 5 | SC |
| No common name | Hypericum dolabriforme | - | 3 | RT |
| No common name | Hypericum lissophloeus | - | 4 | SC |
| No common name | ictalurus species | - | 2 | SU |
| No common name | Ilex opaca arenicola | - | 4 | RT |
| No common name | Ilex sintenisii | - | 4 | E |
| No common name | Illicium parviflorum | - | 4 | SC |
| No common name | Ipomoea cairica lineariloba | - | 1 | RT |
| No common name | Ipomoea cardiophylla | - | 2 | RT |
| No common name | Ipomopsis aggregata webberi | - | 6 | SC |
| No common name | Ipomopsis globularis | - | 6 | RT |
| No common name | Ipomopsis spicata robruthii | - | 6 | SC |
| No common name | Ironoquia plattensis | - | 6 | UR |
| No common name | Ivesia cryptocaulis | - | 1 | SC |
| No common name | Ivesia jaegeri | - | 1 | SC |
| No common name | Ivesia longibracteata | - | 1 | SC |
| No common name | Ivesia shockleyi ostleri | - | 6 | SC |
| No common name | Jamesia americana zionis | - | 6 | SC |
| No common name | Jamesia tetrapetala | - | 6 | SC |
| No common name | Jaquinia umbellata | - | 4 | RT |
| No common name | Juncus slwookoorum | - | 7 | RT |
| No common name | Juncus trifidus carolinianus | - | 4 | RT |
| No common name | Justicia borinquensis | - | 4 | SC |
| No common name | Justicia culebritae | - | 4 | SC |
| No common name | Justicia warnockii | - | 2 | RT |
| No common name | juturnia tularosae | - | 2 | SU |
| No common name | Kalmiopsis leachiana | - | 1 | RT |
| No common name | Keysseria (=Lagenifera) erici | - | 1 | E |
| No common name | Keysseria (=Lagenifera) helenae | - | 1 | E |
| No common name | Kosteletzkya smilacifolia | - | 4 | RT |
| No common name | Labordia baillonii | - | 1 | RT |
| No common name | Labordia decurrens decurrens | - | 1 | RT |
| No common name | Labordia fagraeoidea longisepala | - | 1 | RT |
| No common name | Labordia fagraeoidea saint-johniana | - | 1 | RT |
| No common name | Labordia fagraeoidea waianaeana | - | 1 | RT |
| No common name | Labordia glabra | - | 1 | RT |
| No common name | Labordia hedyosmifolia kilaueana | - | 1 | RT |
| No common name | Labordia hedyosmifolia magnifolia | - | 1 | RT |
| No common name | Labordia hedyosmifolia robusta | - | 1 | RT |
| No common name | Labordia hedyosmifolia rockii | - | 1 | RT |
| No common name | Labordia hedyosmifolia skottsbergii | - | 1 | RT |
| No common name | Labordia hirtella imbricata | - | 1 | RT |
| No common name | Labordia hirtella laevis | - | 1 | RT |
| No common name | Labordia hirtella laevisepala | - | 1 | RT |
| No common name | Labordia hirtella microcalyx | - | 1 | RT |
| No common name | Labordia hirtella microphylla | - | 1 | RT |
| No common name | Labordia kaalae brachypoda | - | 1 | RT |
| No common name | Labordia kaalae fosbergii | - | 1 | RT |
| No common name | Labordia kaalae mendax | - | 1 | RT |
| No common name | Labordia molokaiana molokaiana | - | 1 | RT |
| No common name | Labordia molokaiana munroi | - | 1 | RT |
| No common name | Labordia molokaiana setosa | - | 1 | RT |
| No common name | Labordia nelsonii | - | 1 | RT |
| No common name | Labordia olympiana | - | 1 | RT |
| No common name | Labordia pallida | - | 1 | RT |
| No common name | Labordia pedunculata | - | 1 | RT |
| No common name | Labordia tinifolia euphorbioidea | - | 1 | RT |
| No common name | Labordia tinifolia forbesii | - | 1 | RT |
| No common name | Labordia tinifolia honolulensis | - | 1 | RT |
| No common name | Labordia tinifolia microgyna | - | 1 | RT |
| No common name | Labordia tinifolia parvifolia | - | 1 | RT |
| No common name | Labordia tinifolia tenuifolia | - | 1 | RT |
| No common name | Labordia wawrana | - | 1 | RT |
| No common name | Lachnocaulon beyrichianum | - | 4 | RT |
| No common name | Lantana depressa | - | 4 | SC |
| No common name | Lathyrus holochlorus | - | 1 | RT |
| No common name | Leavenworthia exigua exigua | - | 4 | RT |
| No common name | Leavenworthia stylosa | - | 4 | RT |
| No common name | Lecanora xanthosora | - | 1 | SC |
| No common name | Lechea cernua | - | 4 | RT |
| No common name | Lechea divaricata | - | 4 | SC |
| No common name | Lechea lakelae | - | 4 | SC |
| No common name | Lejeunea blomquistii | - | 4 | SC |
| No common name | Lepanthes dodiana | - | 4 | RT |
| No common name | Lepanthes eltoroensis | - | 4 | E |
| No common name | Lepidium montanum neeseae | - | 6 | RT |
| No common name | Lepidium nanum | - | 1 | RT |
| No common name | Lepidium ostleri | - | 6 | UR |
| No common name | Leptocereus grantianus | - | 4 | E |
| No common name | Leptodactylon glabrum | - | 1 | SC |
| No common name | Leptodactylon pungens hazeliae | - | 1 | SC |
| No common name | Lesquerella arctica scammanae | - | 7 | RT |
| No common name | Lesquerella condensata | - | 6 | RT |
| No common name | lesquerella navajoensis | - | 2 | UR |
| No common name | Lessingia arachnoidea | - | 1 | SC |
| No common name | Lessingia micradenia glabrata | - | 1 | SC |
| No common name | Lessingia micradenia micradenia | - | 1 | SC |
| No common name | Lewisia columbiana wallowensis | - | 1 | RT |
| No common name | Lewisia cotyledon purdyi | - | 1 | SC |
| No common name | Lewisia maguirei | - | 1 | SC |
| No common name | Lewisia tweedyi | - | 1 | RT |
| No common name | Liatris cymosa | - | 2 | RT |
| No common name | Ligusticum porteri brevilobum | - | 6 | RT |
| No common name | Lilaeopsis carolinensis | - | 4 | RT |
| No common name | Limbella fryei | - | 1 | SC |
| No common name | Limnanthes gracilis gracilis | - | 1 | SC |
| No common name | Limonium limbatum | - | 2 | RT |
| No common name | Lindera subcoriacea | - | 4 | SC |
| No common name | Linum sulcatum harperi | - | 4 | SC |
| No common name | Lipochaeta heterophylla heterophylla | - | 1 | RT |
| No common name | Lipochaeta integrifolia argentea | - | 1 | RT |
| No common name | Lipochaeta intermedia | - | 1 | RT |
| No common name | Lipochaeta lavarum conferta | - | 1 | RT |
| No common name | Lipochaeta lavarum hillebrandiana | - | 1 | RT |
| No common name | Lipochaeta lavarum maneleana | - | 1 | RT |
| No common name | Lipochaeta lavarum ovata | - | 1 | RT |
| No common name | Lipochaeta lavarum stearnsii | - | 1 | RT |
| No common name | Lipochaeta ovata | - | 1 | RT |
| No common name | Lipochaeta porophila | - | 1 | RT |
| No common name | Lipochaeta venosa | - | 1 | E |
| No common name | litodonta alpina | - | 2 | SU |
| No common name | Lobelia appendiculata gattingeri | - | 4 | RT |
| No common name | Lobelia dunbariae | - | 1 | SC |
| No common name | Lobelia gaudichaudii ssp. koolauensis | - | 1 | E |
| No common name | Lobelia hypoleuca rockii | - | 1 | RT |
| No common name | Lobelia monostachya | - | 1 | E |
| No common name | Lobelia niihauensis | - | 1 | E |
| No common name | Lobelia oahuensis | - | 1 | E |
| No common name | Lobelia remyi | - | 1 | RT |
| No common name | Lomatium attenuatum | - | 6 | RT |
| No common name | Lomatium cuspidatum | - | 1 | RT |
| No common name | Lomatium hendersonii | - | 1 | RT |
| No common name | Lomatium laevigatum | - | 1 | RT |
| No common name | Lomatium minimum | - | 6 | RT |
| No common name | Lomatium nelsonianum | - | 1 | RT |
| No common name | Lomatium oreganum | - | 1 | RT |
| No common name | Lomatium quintuplex | - | 1 | RT |
| No common name | Lomatium rollinsii | - | 1 | RT |
| No common name | Lomatium serpentinum | - | 1 | RT |
| No common name | Lomatium thompsonii | - | 1 | RT |
| No common name | Lophocolea appalachiana | - | 4 | SC |
| No common name | Lotus purshianus helleri | - | 4 | SC |
| No common name | Luina serpentina | - | 1 | SC |
| No common name | Lunania buchii | - | 4 | SC |
| No common name | Lupinus burkei caeruleomontanus | - | 1 | RT |
| No common name | Lupinus crassus | - | 6 | SC |
| No common name | Lupinus cutleri | - | 2 | RT |
| No common name | Lupinus jonesii | - | 6 | RT |
| No common name | Lupinus malacophyllus | - | 1 | RT |
| No common name | Lupinus montigenus montigenus | - | 1 | RT |
| No common name | Lupinus mucronulatus | - | 1 | RT |
| No common name | Lupinus sabinii | - | 1 | RT |
| No common name | Lupinus sericeus marianus | - | 6 | RT |
| No common name | Luzula hawaiiensis oahuensis | - | 1 | RT |
| No common name | lycaena ferrisi | - | 2 | SU |
| No common name | Lycopodium haleakalae | - | 1 | RT |
| No common name | Lygodesmia grandiflora stricta | - | 6 | RT |
| No common name | Lyonia truncata var. proctorii | - | 4 | E |
| No common name | Lysiloma microphylla thornberi | - | 2 | RT |
| No common name | Lysimachia filifolia | - | 1 | E |
| No common name | Lysimachia forbesii | - | 1 | RT |
| No common name | Lysimachia iniki | - | 1 | E |
| No common name | Lysimachia kalalauensis | - | 1 | SC |
| No common name | Lysimachia lydgatei | - | 1 | E |
| No common name | Lysimachia maxima | - | 1 | E |
| No common name | Lysimachia pendens | - | 1 | E |
| No common name | Lysimachia scopulensis | - | 1 | E |
| No common name | Lysimachia venosa | - | 1 | E |
| No common name | Lythrum curtissii | - | 4 | SC |
| No common name | Lythrum flagellare | - | 4 | SC |
| No common name | Lythrum ovalifolium | - | 2 | RT |
| No common name | Machaeranthera ammophila | - | 1 | RT |
| No common name | Machaeranthera arizonica | - | 2 | RT |
| No common name | Machaeranthera grindelioides depressa | - | 6 | RT |
| No common name | Machaeranthera gypsitherma | - | 2 | SC |
| No common name | Machaeranthera laetevirens | - | 1 | RT |
| No common name | Machaeranthera leucanthemifolia | - | 1 | RT |
| No common name | Machaeranthera mucronata | - | 2 | RT |
| No common name | Malacothrix crispifolia | - | 1 | SC |
| No common name | Malacothrix intermedia | - | 1 | SC |
| No common name | Malvastrum hispidum | - | 3 | RT |
| No common name | Mammillaria orestera | - | 2 | RT |
| No common name | Mammillaria thornberi | - | 2 | RT |
| No common name | Manfreda maculosa | - | 2 | RT |
| No common name | Manihot davisiae | - | 2 | RT |
| No common name | Mappia racemosa | - | 4 | SC |
| No common name | Mariscus fauriei | - | 1 | E |
| No common name | Mariscus kunthianus | - | 1 | SC |
| No common name | Mariscus pennatiformis | - | 1 | E |
| No common name | Mariscus rockii | - | 1 | SC |
| No common name | Mariscus urbanii | - | 4 | SC |
| No common name | Marsdenia elliptica | - | 4 | SC |
| No common name | Marshallia ramosa | - | 4 | SC |
| No common name | marstonia comalensis | - | 2 | SU |
| No common name | Matelea brevicoronata | - | 2 | RT |
| No common name | Matelea floridana | - | 4 | SC |
| No common name | Matelea parviflora | - | 2 | RT |
| No common name | Maytenus cymosa | - | 4 | SC |
| No common name | Melanoplus missoulae | - | 6 | SC |
| No common name | melanoplus species | - | 2 | SU |
| No common name | melanoplus species | - | 2 | SU |
| No common name | melanoplus speciesfiftytwo | - | 2 | SU |
| No common name | melanoplus speciesfortyeight | - | 2 | SU |
| No common name | melanoplus speciessixtytwo | - | 2 | SU |
| No common name | melanoplus speciesthirtysix | - | 2 | SU |
| No common name | melanoplus speciestwentysix | - | 2 | SU |
| No common name | melanoplus speciestwentytwo | - | 2 | SU |
| No common name | Melanthera parvifolia | - | 4 | SC |
| No common name | mentzelia memorabalis | - | 2 | SU |
| No common name | Mentzelia multicaulis labrina | - | 6 | SC |
| No common name | Mentzelia shultziorum | - | 6 | SC |
| No common name | Mesadenus portoricensis | - | 4 | RT |
| No common name | Metrosideros collina newellii | - | 1 | RT |
| No common name | mexichthonius exoticus | - | 2 | SU |
| No common name | Microseris howellii | - | 1 | SC |
| No common name | Microseris laciniata detlingii | - | 1 | SC |
| No common name | Microseris nutans siskiyouensis | - | 1 | RT |
| No common name | Mimulus hymenophyllus | - | 1 | SC |
| No common name | Mimulus jungermannioides | - | 1 | SC |
| No common name | Mimulus washoensis | - | 1 | RT |
| No common name | Minuartia godfreyi | - | 4 | SC |
| No common name | Minuartia marcescens | - | 5 | SC |
| No common name | Minuartia uniflora | - | 4 | RT |
| No common name | Mitracarpus maxwelliae | - | 4 | E |
| No common name | Mitracarpus polycladus | - | 4 | E |
| No common name | Monardella diaboli | - | 1 | RT |
| No common name | Monotropa brittonii | - | 4 | SC |
| No common name | Montia bostockii | - | 7 | RT |
| No common name | Muhlenbergia pilosa | - | 2 | RT |
| No common name | Munroidendron racemosum | - | 1 | E |
| No common name | Musineon lineare | - | 6 | RT |
| No common name | Myrcia paganii | - | 4 | E |
| No common name | Myriophyllum laxum | - | 4 | SC |
| No common name | Najas filifolia | - | 4 | SC |
| No common name | Nama retrorsum | - | 2 | RT |
| No common name | Nama xylopodum | - | 2 | RT |
| No common name | Napaea dioica | - | 3 | RT |
| No common name | neoallochernes incertus | - | 2 | SU |
| No common name | neoleptoneta anopica | - | 2 | SU |
| No common name | neoleptoneta concinna | - | 2 | SU |
| No common name | neoleptoneta devia | - | 2 | SU |
| No common name | neoleptoneta valverde | - | 2 | SU |
| No common name | Neoparrya lithophila | - | 6 | RT |
| No common name | Neotrichia downsi | - | 6 | SC |
| No common name | Neraudia angulata | - | 1 | E |
| No common name | Neraudia kauaiensis | - | 1 | RT |
| No common name | Neraudia ovata | - | 1 | E |
| No common name | Neraudia sericea | - | 1 | E |
| No common name | Nesogenes rotensis | - | 1 | E |
| No common name | Nestronia umbellula | - | 4 | RT |
| No common name | Neviusia alabamensis | - | 4 | SC |
| No common name | Notholaena schaffneri | - | 2 | RT |
| No common name | Nototrichium sandwicense decipiens | - | 1 | RT |
| No common name | Nototrichium sandwicense dubium | - | 1 | RT |
| No common name | Nototrichium sandwicense forbesii | - | 1 | RT |
| No common name | Nototrichium sandwicense helleri | - | 1 | RT |
| No common name | Nototrichium sandwicense kolekolense | - | 1 | RT |
| No common name | Nototrichium sandwicense lanaiense | - | 1 | RT |
| No common name | Nototrichium sandwicense lanceolatum | - | 1 | RT |
| No common name | Nototrichium sandwicense latifolium | - | 1 | RT |
| No common name | Nototrichium sandwicense leptopodum | - | 1 | RT |
| No common name | Nototrichium sandwicense longespicatum | - | 1 | RT |
| No common name | Nototrichium sandwicense macrophyllum | - | 1 | RT |
| No common name | Nototrichium sandwicense mauiense | - | 1 | RT |
| No common name | Nototrichium sandwicense niihauense | - | 1 | RT |
| No common name | Nototrichium sandwicense olokeleanum | - | 1 | RT |
| No common name | Nototrichium sandwicense pulchelloides | - | 1 | RT |
| No common name | Nototrichium sandwicense pulchellum | - | 1 | RT |
| No common name | Nototrichium sandwicense subcordatum | - | 1 | RT |
| No common name | Nototrichium sandwicense syringifolium | - | 1 | RT |
| No common name | Nototrichium viride | - | 1 | RT |
| No common name | Nuphar luteum ulvaceum | - | 4 | SC |
| No common name | Ochrosia compta | - | 1 | RT |
| No common name | Oncopodura cruciata | - | 6 | SC |
| No common name | Onosmodium helleri | - | 2 | RT |
| No common name | Onosmodium molle molle | - | 4 | RT |
| No common name | Operculina triquetra | - | 4 | SC |
| No common name | Ophioglossum dendroneuron | - | 4 | RT |
| No common name | Opuntia basilaris longiareolata | - | 2 | RT |
| No common name | Opuntia basilaris woodburyi | - | 6 | RT |
| No common name | Opuntia heacockul | - | 6 | SC |
| No common name | Opuntia phaeacantha flavispina | - | 2 | RT |
| No common name | Opuntia phaeacantha mojavensis | - | 2 | RT |
| No common name | Opuntia phaeacantha superbospina | - | 2 | RT |
| No common name | Opuntia spinosissima | - | 4 | SC |
| No common name | Opuntia triacantha | - | 4 | RT |
| No common name | Oreoxis trotteri | - | 6 | SC |
| No common name | Oryzopsis contracta | - | 6 | SC |
| No common name | Oryzopsis swallenii | - | 1 | RT |
| No common name | Osmoxylon mariannense | - | 1 | E |
| No common name | Oxypolis ternata | - | 4 | SC |
| No common name | Oxytheca watsonii | - | 1 | RT |
| No common name | Oxytropis besseyi obnapiformis | - | 6 | RT |
| No common name | Oxytropis campestris johannensis | - | 5 | RT |
| No common name | Oxytropis campestris wanapum | - | 1 | SC |
| No common name | Oxytropis glaberrima | - | 7 | RT |
| No common name | Oxytropis jonesii | - | 6 | RT |
| No common name | Oxytropis sordida barnebyana | - | 7 | SC |
| No common name | Panicum lithophilum | - | 4 | RT |
| No common name | Panicum nudicaule | - | 4 | SC |
| No common name | Panicum pinetorum | - | 4 | SC |
| No common name | Panicum stevensianum | - | 4 | SC |
| No common name | Papaver pygmaeum | - | 6 | SC |
| No common name | Paronychia chorizanthoides | - | 2 | RT |
| No common name | Paronychia drummondii parviflora | - | 2 | RT |
| No common name | Paronychia monticola | - | 2 | RT |
| No common name | Paronychia nudata | - | 2 | RT |
| No common name | Paronychia virginica parksii | - | 2 | RT |
| No common name | Parrya nudicaulis | - | 6 | RT |
| No common name | Parthenium alpinum | - | 6 | RT |
| No common name | Passiflora berteroana | - | 4 | SC |
| No common name | Passiflora bilobata | - | 4 | SC |
| No common name | Passiflora murucuja | - | 4 | RT |
| No common name | Paxistima canbyi | - | 3 | SC |
| No common name | Pectis imberbis | - | 2 | SC |
| No common name | Pedicularis rainierensis | - | 1 | RT |
| No common name | Pedicularis semibarbata charlestonensis | - | 1 | SC |
| No common name | Pediomelum aromaticum tuhyi | - | 6 | SC |
| No common name | Pediomelum pariensis | - | 6 | SC |
| No common name | Pelea anisata haupuana | - | 1 | RT |
| No common name | Pelea clusiaefolia pickeringii | - | 1 | RT |
| No common name | Pelea elliptica mauiensis | - | 1 | RT |
| No common name | Pelea grandifolia lianoides | - | 1 | RT |
| No common name | Pelea grandifolia montana | - | 1 | RT |
| No common name | Pelea grandifolia ovalifolia | - | 1 | RT |
| No common name | Pelea hiiakae | - | 1 | RT |
| No common name | Pelea hosakae | - | 1 | RT |
| No common name | Pelea lakae | - | 1 | RT |
| No common name | Pelea lanceolata | - | 1 | RT |
| No common name | Pelea oblongifolia | - | 1 | RT |
| No common name | Pelea olowaluensis | - | 1 | RT |
| No common name | Pelea parvifolia sessilis | - | 1 | RT |
| No common name | Pelea peduncularis cordata | - | 1 | RT |
| No common name | Pelea peduncularis niuensis | - | 1 | RT |
| No common name | Pelea peduncularis nummularia | - | 1 | RT |
| No common name | Pelea pickeringii | - | 1 | RT |
| No common name | Pelea puauluensis | - | 1 | RT |
| No common name | Pelea volcanica kohalae | - | 1 | RT |
| No common name | Pelea wahiawaensis | - | 1 | RT |
| No common name | Pelea waimeaensis | - | 1 | RT |
| No common name | Penstemon ammophilum | - | 6 | SC |
| No common name | Penstemon angustifolius vernalensis | - | 6 | RT |
| No common name | Penstemon arenarius | - | 1 | SC |
| No common name | Penstemon atwoodii | - | 6 | RT |
| No common name | Penstemon baccharifolius | - | 2 | RT |
| No common name | Penstemon barrettiae | - | 1 | SC |
| No common name | Penstemon bicolor bicolor | - | 1 | SC |
| No common name | Penstemon bicolor roseus | - | 1 | SC |
| No common name | Penstemon cobaea purpureus | - | 3 | RT |
| No common name | Penstemon crandallii atractus | - | 6 | SC |
| No common name | Penstemon dissectus | - | 4 | RT |
| No common name | Penstemon elegantulus | - | 1 | RT |
| No common name | Penstemon floribundus | - | 1 | SC |
| No common name | Penstemon flowersii | - | 6 | UR |
| No common name | Penstemon francisci-pennellii | - | 1 | RT |
| No common name | Penstemon goodrichii | - | 6 | SC |
| No common name | Penstemon humilis brevifolius | - | 6 | RT |
| No common name | Penstemon humilis obtusifolius | - | 6 | RT |
| No common name | Penstemon leptanthus | - | 6 | SC |
| No common name | Penstemon moriahensis | - | 1 | RT |
| No common name | Penstemon multicaulis | - | 4 | RT |
| No common name | Penstemon navajoa | - | 6 | SC |
| No common name | Penstemon parviflorus | - | 6 | SC |
| No common name | Penstemon patricus | - | 1 | RT |
| No common name | Penstemon peckii | - | 1 | SC |
| No common name | Penstemon procerus modestus | - | 1 | RT |
| No common name | Penstemon pudicus | - | 1 | SC |
| No common name | Penstemon thompsoniae jaegeri | - | 1 | RT |
| No common name | Penstemon thurberi anestius | - | 1 | RT |
| No common name | Penstemon virgatus pseudoputus | - | 2 | RT |
| No common name | Penstemon washingtonensis | - | 1 | RT |
| No common name | Penstemon yampaensis | - | 6 | RT |
| No common name | Peperomia cookiana minutilimba | - | 1 | RT |
| No common name | Peperomia cornifolia | - | 1 | RT |
| No common name | Peperomia degeneri | - | 1 | SC |
| No common name | Peperomia expallescens brevipilosa | - | 1 | RT |
| No common name | Peperomia fauriei | - | 1 | RT |
| No common name | Peperomia floridana | - | 4 | RT |
| No common name | Peperomia forbesii | - | 1 | RT |
| No common name | Peperomia haupuensis | - | 1 | RT |
| No common name | Peperomia helleri knudsenii | - | 1 | RT |
| No common name | Peperomia lilifolia obtusata | - | 1 | RT |
| No common name | Peperomia maunakeana | - | 1 | RT |
| No common name | Peperomia megalopoda | - | 4 | SC |
| No common name | Peperomia myrtifolia | - | 4 | RT |
| No common name | Peperomia oahuensis st-johnii | - | 1 | RT |
| No common name | Peperomia plinervata | - | 1 | RT |
| No common name | Peperomia rigidilimba | - | 1 | RT |
| No common name | Peperomia rockii | - | 1 | SC |
| No common name | Peperomia treleasei | - | 1 | RT |
| No common name | Peperomia waikamoiana | - | 1 | RT |
| No common name | Perityle lemmonii | - | 2 | RT |
| No common name | Perityle megalocephala intricata | - | 1 | RT |
| No common name | Perityle parryi | - | 2 | RT |
| No common name | Perityle specuicola | - | 6 | SC |
| No common name | Perityle staurophylla | - | 2 | RT |
| No common name | Persea borbonia humilis | - | 4 | RT |
| No common name | Persicaria paludicola | - | 4 | RT |
| No common name | Peteria thompsonae | - | 6 | RT |
| No common name | Petrophytum hendersonii | - | 1 | RT |
| No common name | Phacelia constancei | - | 2 | RT |
| No common name | Phacelia dubia georgiana | - | 4 | RT |
| No common name | Phacelia glaberrima | - | 1 | RT |
| No common name | Phacelia inconspicua | - | 1 | SC |
| No common name | Phacelia integrifolia texana | - | 2 | RT |
| No common name | Phacelia nevadensis | - | 1 | RT |
| No common name | Phacelia peckii | - | 1 | RT |
| No common name | Phacelia verna | - | 1 | RT |
| No common name | Pheidole elecebra | - | 6 | SC |
| No common name | Phialanthus myrtilloides | - | 4 | SC |
| No common name | Philadelphus mearnsii | - | 2 | RT |
| No common name | Philadelphus texensis texensis | - | 2 | RT |
| No common name | philomycus bisdodus | - | 2 | SU |
| No common name | Phlox buckleyi | - | 5 | RT |
| No common name | Phlox peckii | - | 1 | RT |
| No common name | Phyllanthus liebmannianus platylepis | - | 4 | RT |
| No common name | Phyllanthus pentaphyllus floridanus | - | 4 | SC |
| No common name | Phyllanthus sandwicensis degeneri | - | 1 | RT |
| No common name | Phyllostegia bracteata | - | 1 | C |
| No common name | Phyllostegia brevidens | - | 1 | RT |
| No common name | Phyllostegia brevidens ambigua | - | 1 | RT |
| No common name | Phyllostegia brevidens degeneri | - | 1 | RT |
| No common name | Phyllostegia brevidens heterodoxa | - | 1 | RT |
| No common name | Phyllostegia brevidens hirsutula | - | 1 | RT |
| No common name | Phyllostegia brevidens pubescens | - | 1 | RT |
| No common name | Phyllostegia floribunda | - | 1 | C |
| No common name | Phyllostegia glabra var. lanaiensis | - | 1 | E |
| No common name | Phyllostegia helleri | - | 1 | RT |
| No common name | Phyllostegia hillebrandii | - | 1 | RT |
| No common name | Phyllostegia hirsuta | - | 1 | E |
| No common name | Phyllostegia hispida | - | 1 | E |
| No common name | Phyllostegia imminuta | - | 1 | RT |
| No common name | Phyllostegia kaalaensis | - | 1 | E |
| No common name | Phyllostegia knudsenii | - | 1 | E |
| No common name | Phyllostegia ledyardii | - | 1 | RT |
| No common name | Phyllostegia longimontis | - | 1 | RT |
| No common name | Phyllostegia mannii | - | 1 | E |
| No common name | Phyllostegia mollis | - | 1 | E |
| No common name | Phyllostegia mollis fagerlindii | - | 1 | RT |
| No common name | Phyllostegia parviflora | - | 1 | E |
| No common name | Phyllostegia renovans | - | 1 | E |
| No common name | Phyllostegia rockii | - | 1 | RT |
| No common name | Phyllostegia variabilis | - | 1 | RT |
| No common name | Phyllostegia velutina | - | 1 | E |
| No common name | Phyllostegia waimeae | - | 1 | E |
| No common name | Phyllostegia warshaueri | - | 1 | E |
| No common name | Phyllostegia wawrana | - | 1 | E |
| No common name | Physalis viscosa elliotii | - | 4 | RT |
| No common name | Physaria acutifolia purpurea | - | 6 | RT |
| No common name | Physaria bellii | - | 6 | SC |
| No common name | Physaria didymocarpa lyrata | - | 1 | SC |
| No common name | Physaria dornii | - | 6 | SC |
| No common name | Physaria eburniflora | - | 6 | SC |
| No common name | Physaria geyeri purpurea | - | 1 | RT |
| No common name | Physostegia leptophylla | - | 4 | RT |
| No common name | Physostegia longisepala | - | 4 | SC |
| No common name | Physostegia micrantha | - | 2 | RT |
| No common name | Pieris phillyreifolia | - | 4 | RT |
| No common name | Pilea leptophylla | - | 4 | SC |
| No common name | Pilea multicaulis | - | 4 | SC |
| No common name | Pilea richardii | - | 4 | SC |
| No common name | Pilea yunquensis | - | 4 | RT |
| No common name | Pinckneya bracteata | - | 4 | RT |
| No common name | Pisonia floridana | - | 4 | RT |
| No common name | Pisonia wagneriana | - | 1 | SC |
| No common name | Pittosporum acuminatum leptopodum | - | 1 | RT |
| No common name | Pittosporum acuminatum magnifolium | - | 1 | RT |
| No common name | Pittosporum acuminatum waimeanum | - | 1 | RT |
| No common name | Pittosporum argentifolium argentifolium | - | 1 | RT |
| No common name | Pittosporum argentifolium sessile | - | 1 | RT |
| No common name | Pittosporum cauliflorum cauliflorum | - | 1 | RT |
| No common name | Pittosporum cauliflorum cladanthoides | - | 1 | RT |
| No common name | Pittosporum cauliflorum pedicellatum | - | 1 | RT |
| No common name | Pittosporum cladanthum gracilipes | - | 1 | RT |
| No common name | Pittosporum confertiflorum longipes | - | 1 | RT |
| No common name | Pittosporum confertiflorum microphyllum | - | 1 | RT |
| No common name | Pittosporum glabrum glomeratum | - | 1 | RT |
| No common name | Pittosporum glabrum intermedium | - | 1 | RT |
| No common name | Pittosporum glabrum tinifolium | - | 1 | RT |
| No common name | Pittosporum halophiloides | - | 1 | RT |
| No common name | Pittosporum halophilum | - | 1 | RT |
| No common name | Pittosporum hawaiiense | - | 1 | RT |
| No common name | Pittosporum helleri | - | 1 | RT |
| No common name | Pittosporum hosmeri | - | 1 | RT |
| No common name | Pittosporum insigne micranthum | - | 1 | RT |
| No common name | Pittosporum kahananum | - | 1 | RT |
| No common name | Pittosporum kauaiense repens | - | 1 | RT |
| No common name | Pittosporum terminalioides lanaiense | - | 1 | RT |
| No common name | Pittosporum terminalioides macropus | - | 1 | RT |
| No common name | Pittosporum terminalioides mauiense | - | 1 | RT |
| No common name | Pityopsis flexuosa | - | 4 | SC |
| No common name | Plagiobothrys distantiflorus | - | 1 | RT |
| No common name | Plagiobothrys figuratus corallicarpus/ined | - | 1 | SC |
| No common name | Plagiochila caduciloba | - | 4 | SC |
| No common name | Plagiochila columbiana | - | 4 | SC |
| No common name | Plagiochila echinata | - | 4 | SC |
| No common name | Plagiochila virginica euryphylla | - | 4 | SC |
| No common name | Platanthera holochila | - | 1 | E |
| No common name | Platanthera integra | - | 4 | RT |
| No common name | Platydesma cornuta cornuta | - | 1 | C |
| No common name | Platydesma cornuta decurrens | - | 1 | C |
| No common name | Platydesma remyi | - | 1 | C |
| No common name | Plummera ambigens | - | 2 | RT |
| No common name | Plummera floribunda | - | 2 | RT |
| No common name | Poa curtifolia | - | 1 | RT |
| No common name | Poa eyerdamii | - | 7 | RT |
| No common name | Poa laxiflora | - | 1 | RT |
| No common name | Poa marcida | - | 1 | RT |
| No common name | Poa merrilliana | - | 7 | RT |
| No common name | Poa norbergii | - | 7 | RT |
| No common name | Poa siphonoglossa | - | 1 | E |
| No common name | Podistera yukonensis | - | 7 | SC |
| No common name | Polemonium nevadense | - | 1 | RT |
| No common name | Polemonium pectinatum | - | 1 | SC |
| No common name | Polygala alba | - | NA | SU |
| No common name | Polygala boykinii sparsifolia | - | 4 | SC |
| No common name | Polygala paucifolia | - | NA | SU |
| No common name | Polygala piliophora | - | 2 | RT |
| No common name | Polygala rimulicola rimulicola | - | 2 | RT |
| No common name | Polygala subspinosa heterorhynca | - | 1 | RT |
| No common name | Polygala verticillata | - | NA | SU |
| No common name | Polygonum cascadense | - | 1 | RT |
| No common name | Polygonum striatulum | - | 2 | RT |
| No common name | Polygonum utahense | - | 6 | RT |
| No common name | Polymnia laevigata | - | 4 | RT |
| No common name | Polystichum calderonense | - | 4 | E |
| No common name | Porella appalachiana | - | 4 | SC |
| No common name | Porophyllum greggii | - | 2 | RT |
| No common name | Porophyllum pygmaeum | - | 1 | SC |
| No common name | Portulaca caulerpoides | - | 4 | RT |
| No common name | Portulaca molokiniensis | - | 1 | SC |
| No common name | Portulaca smallii | - | 4 | RT |
| No common name | Portulaca villosa | - | 1 | SC |
| No common name | potamilus metnecktayi | - | 2 | UR |
| No common name | Potamogeton floridanus | - | 4 | SC |
| No common name | Potamogeton lateralis | - | 5 | RT |
| No common name | Potamogeton porteri | - | 5 | RT |
| No common name | Potentilla angelliae | - | 6 | SC |
| No common name | Potentilla cottamii | - | 6 | SC |
| No common name | Potentilla multifoliolata | - | 2 | RT |
| No common name | Potentilla sierra-blancae | - | 2 | RT |
| No common name | Priva portoricensis | - | 4 | RT |
| No common name | Proatriplex pleiantha | - | 2 | RT |
| No common name | Prunus alleghaniensis davisii | - | 3 | SC |
| No common name | Prunus havardii | - | 2 | RT |
| No common name | Prunus minutiflora | - | 2 | RT |
| No common name | Prunus murrayana | - | 2 | RT |
| No common name | Prunus texana | - | 2 | RT |
| No common name | Pseudocopaeodes eunus alinea | - | 1 | SU |
| No common name | Pseudocopaeodes eunus flavus | - | 1 | SU |
| No common name | Pseudocopaeodes eunus ssp. | - | 1 | SU |
| No common name | Psoralea subacaulis | - | 4 | RT |
| No common name | Psorothamnus kingii | - | 1 | RT |
| No common name | Psorothamnus polyadenius jonesii | - | 6 | SC |
| No common name | Psorothamnus thompsonae thompsonae | - | 6 | RT |
| No common name | Psorothamnus thompsonae whitingii | - | 2 | SC |
| No common name | Psychotria insularum paradisii | - | 1 | RT |
| No common name | Pteris lidgatei | - | 1 | E |
| No common name | ptomaphagus cocytus | - | 2 | SU |
| No common name | Pycnanthemum curvipes | - | 4 | RT |
| No common name | Pycnanthemum floridanum | - | 4 | RT |
| No common name | pyrgulopsis species | - | 2 | SU |
| No common name | Randia portoricensis | - | 4 | SC |
| No common name | Ranunculus austro-oreganus | - | 1 | SC |
| No common name | Ranunculus occidentalis nelsonii | - | 7 | RT |
| No common name | Ranunculus reconditus | - | 1 | SC |
| No common name | Rauvolfia helleri | - | 1 | RT |
| No common name | Rauvolfia mauiensis | - | 1 | RT |
| No common name | Rauvolfia molokaiensis parvifolia | - | 1 | RT |
| No common name | Rauvolfia sandwicensis subacuminata | - | 1 | RT |
| No common name | Remya kauaiensis | - | 1 | E |
| No common name | Remya montgomeryi | - | 1 | E |
| No common name | rhadine austinica | - | 2 | SU |
| No common name | rhadine insolita | - | 2 | SU |
| No common name | rhadine noctivaga | - | 2 | SU |
| No common name | rhadine russelli | - | 2 | SU |
| No common name | Rhinanthus arcticus | - | 7 | RT |
| No common name | Rhipsalis baccifera | - | 4 | RT |
| No common name | Rhododon ciliatus | - | 2 | RT |
| No common name | Rhynchosia cinerea | - | 4 | RT |
| No common name | Rhysopterus plurijugus | - | 1 | RT |
| No common name | Rollandia angustifolia ochreata | - | 1 | RT |
| No common name | Rollandia degenerana | - | 1 | RT |
| No common name | Rollandia parvifolia | - | 1 | RT |
| No common name | Rollandia purpurellifolia | - | 1 | RT |
| No common name | Rollandia sessilifolia | - | 1 | RT |
| No common name | Romanzoffia thompsonii | - | 1 | RT |
| No common name | Rorippa calycina | - | 6 | SC |
| No common name | Rosa stellata stellata | - | 2 | RT |
| No common name | Rubus bartonianus | - | 1 | SC |
| No common name | Rubus macraei | - | 1 | SC |
| No common name | Rubus missouricus | - | 3 | RT |
| No common name | Rubus nigerrimus | - | 1 | SC |
| No common name | Rudbeckia auriculata | - | 4 | RT |
| No common name | Rudbeckia heliopsidis | - | 4 | SC |
| No common name | Rudbeckia triloba pinnatiloba | - | 4 | SC |
| No common name | Ruellia drummondiana | - | 2 | RT |
| No common name | Rumex spiralis | - | 2 | RT |
| No common name | Sageretia minutiflora | - | 4 | RT |
| No common name | Salvia dorrii clokeyi | - | 1 | SC |
| No common name | Sanicula kauaiensis | - | 1 | SC |
| No common name | Sanicula mariversa | - | 1 | E |
| No common name | Sanicula purpurea | - | 1 | E |
| No common name | Sanicula sandwicensis | - | 1 | SC |
| No common name | Santalum ellipticum littorale | - | 1 | RT |
| No common name | Santalum salicifolium | - | 1 | RT |
| No common name | Saussurea weberi | - | 6 | RT |
| No common name | Saxifraga bryophora tobiasiae | - | 1 | SC |
| No common name | Scaevola skottsbergii | - | 1 | RT |
| No common name | Schiedea attenuata | - | 1 | E |
| No common name | Schiedea haleakalensis | - | 1 | E |
| No common name | Schiedea helleri | - | 1 | E |
| No common name | Schiedea hookeri | - | 1 | E |
| No common name | Schiedea implexa | - | 1 | RT |
| No common name | Schiedea kaalae | - | 1 | E |
| No common name | Schiedea kauaiensis | - | 1 | E |
| No common name | Schiedea lydgatei | - | 1 | E |
| No common name | Schiedea mannii | - | 1 | RT |
| No common name | Schiedea membranacea | - | 1 | E |
| No common name | Schiedea menziesii | - | 1 | SC |
| No common name | Schiedea nuttallii | - | 1 | E |
| No common name | Schiedea salicaria | - | 1 | C |
| No common name | Schiedea sarmentosa | - | 1 | E |
| No common name | Schiedea spergulina var. leiopoda | - | 1 | E |
| No common name | Schiedea spergulina var. spergulina | - | 1 | T |
| No common name | Schiedea verticillata | - | 1 | E |
| No common name | Schisandra glabra | - | 4 | RT |
| No common name | Schizachyrium niveum | - | 4 | SC |
| No common name | Schizachyrium rhizomatum | - | 4 | RT |
| No common name | Schoepfia arenaria | - | 4 | T |
| No common name | Scleria doradoensis | - | 4 | RT |
| No common name | Sclerocactus contortus | - | 6 | SC |
| No common name | Sclerocactus spinosior | - | 6 | RT |
| No common name | Sclerocactus whipplei heilii | - | 2 | RT |
| No common name | Sclerocactus whipplei reevesii | - | 2 | RT |
| No common name | Selaginella utahensis | - | 6 | RT |
| No common name | Senecio cardamine | - | 2 | RT |
| No common name | Senecio hesperius | - | 1 | SC |
| No common name | Senecio lynceus leucoreus | - | 1 | RT |
| No common name | Senecio neowebsteri | - | 1 | RT |
| No common name | Senecio quaerens | - | 2 | SC |
| No common name | senecio quaylei | - | 2 | SU |
| No common name | Senecio sandvicensis | - | 1 | RT |
| No common name | Senecio warnockii | - | 2 | RT |
| No common name | Seymeria havardii | - | 2 | RT |
| No common name | Shoshonea pulvinata | - | 6 | SC |
| No common name | Sibara grisea | - | 2 | RT |
| No common name | Sibara rosulata | - | 1 | RT |
| No common name | Sicyos hillebrandii | - | 1 | RT |
| No common name | Sicyos laysanensis | - | 1 | RT |
| No common name | Sicyos maximowiczii | - | 1 | RT |
| No common name | Sicyos nihoaensis | - | 1 | RT |
| No common name | Sicyos semitonsus | - | 1 | RT |
| No common name | Sida inflexa | - | 5 | SC |
| No common name | Sida ledyardii | - | 1 | RT |
| No common name | Sida nelsonii | - | 1 | RT |
| No common name | Sida rubromarginata | - | 4 | RT |
| No common name | Sidalcea candida | - | 6 | RT |
| No common name | Sidalcea cusickii | - | 1 | RT |
| No common name | Sidalcea setosa | - | 1 | RT |
| No common name | Silene alexandri | - | 1 | E |
| No common name | Silene aperta | - | 1 | RT |
| No common name | Silene clokeyi | - | 1 | SC |
| No common name | Silene cryptopetala | - | 1 | RT |
| No common name | Silene degeneri | - | 1 | RT |
| No common name | Silene hawaiiensis | - | 1 | T |
| No common name | Silene lanceolata | - | 1 | E |
| No common name | Silene perlmanii | - | 1 | E |
| No common name | Silene scaposa lobata | - | 1 | RT |
| No common name | Silene scaposa scaposa | - | 1 | RT |
| No common name | Silene seelyi | - | 1 | SC |
| No common name | Silene wrightii | - | 2 | RT |
| No common name | Silphium confertifolium | - | 4 | SC |
| No common name | Sisymbrium kearneyi | - | 2 | RT |
| No common name | Smelowskia borealis villosa | - | 7 | RT |
| No common name | Smelowskia holmgrenii | - | 1 | RT |
| No common name | Smelowskia pyriformis | - | 7 | SC |
| No common name | Smilax leptanthera | - | 4 | SC |
| No common name | Smilax melastomifolia melastomifolia | - | 1 | RT |
| No common name | Solanum carolinense floridanum | - | 4 | RT |
| No common name | Solanum mucronatum | - | 4 | SC |
| No common name | Solanum woodburyi | - | 4 | RT |
| No common name | Solidago arguta harrissii | - | 5 | RT |
| No common name | Solidago lindheimeriana | - | 2 | RT |
| No common name | Solidago mollis angustata | - | 2 | RT |
| No common name | Solidago ouachitensis | - | 4 | RT |
| No common name | Solidago sphathulata gillmanii | - | 3 | SC |
| No common name | sonorarctia fervida | - | 2 | SU |
| No common name | sonorella huecoensis | - | 2 | SU |
| No common name | sonorella pedregosensis | - | 2 | SU |
| No common name | sonorella species | - | 2 | SU |
| No common name | Sophora arizonica | - | 2 | RT |
| No common name | Sophora chrysophylla circularis | - | 1 | RT |
| No common name | Sophora chrysophylla elliptica | - | 1 | RT |
| No common name | Sophora chrysophylla glabrata | - | 1 | RT |
| No common name | Sophora chrysophylla grisea | - | 1 | RT |
| No common name | Sophora chrysophylla kanaioensis | - | 1 | RT |
| No common name | Sophora chrysophylla kauensis | - | 1 | RT |
| No common name | Sophora chrysophylla lanaiensis | - | 1 | RT |
| No common name | Sophora chrysophylla makuaensis | - | 1 | RT |
| No common name | Sophora chrysophylla unifoliata | - | 1 | RT |
| No common name | Sophora formosa | - | 2 | RT |
| No common name | Sophora leachiana | - | 1 | SC |
| No common name | Spermolepis hawaiiensis | - | 1 | E |
| No common name | Sphaeralcea janeae | - | 6 | SC |
| No common name | Sphaeralcea procera | - | 2 | RT |
| No common name | Sphaeralcea psoraloides | - | 6 | SC |
| No common name | sphaeromicola moria | - | 2 | SU |
| No common name | sphingicampa blanchardi | - | 2 | SU |
| No common name | sphingicampa blanchardi | - | 2 | SU |
| No common name | sphingicampa raspa | - | 2 | SU |
| No common name | sphinx eremitoides | - | 2 | SU |
| No common name | sphinx smithi | - | 2 | SU |
| No common name | Spigelia texana | - | 2 | RT |
| No common name | Stanleya pinnata gibberosa | - | 6 | RT |
| No common name | Stenandrium fascicularis | - | 2 | RT |
| No common name | Stenogyne affinis degeneri | - | 1 | RT |
| No common name | Stenogyne angustifolia var. angustifolia | - | 1 | E |
| No common name | Stenogyne bifida | - | 1 | E |
| No common name | Stenogyne campanulata | - | 1 | E |
| No common name | Stenogyne cinerea | - | 1 | RT |
| No common name | Stenogyne cranwelliae | - | 1 | C |
| No common name | Stenogyne glabrata | - | 1 | RT |
| No common name | Stenogyne haliakalae | - | 1 | SC |
| No common name | Stenogyne hirsutula | - | 1 | RT |
| No common name | Stenogyne kanehoana | - | 1 | E |
| No common name | Stenogyne kealiae | - | 1 | E |
| No common name | Stenogyne macrantha | - | 1 | RT |
| No common name | Stenogyne microphylla | - | 1 | RT |
| No common name | Stenogyne mollis | - | 1 | RT |
| No common name | Stenogyne oxygona | - | 1 | SC |
| No common name | Stenogyne purpurea forbesii | - | 1 | RT |
| No common name | Stenogyne rotundifolia oblonga | - | 1 | RT |
| No common name | Stenogyne rugosa mollis | - | 1 | RT |
| No common name | Stenogyne salicifolia | - | 1 | RT |
| No common name | Stenogyne scrophularioides | - | 1 | RT |
| No common name | Stenogyne sessilis hexantha | - | 1 | RT |
| No common name | Stenogyne sessilis laniensis | - | 1 | RT |
| No common name | Stenogyne sessilis wilkesii | - | 1 | RT |
| No common name | Stenogyne sherffii | - | 1 | RT |
| No common name | Stenogyne sororia | - | 1 | RT |
| No common name | Stenogyne viridis | - | 1 | RT |
| No common name | Stillingia sylvatica tenuis | - | 4 | SC |
| No common name | Stipa curvifolia | - | 2 | RT |
| No common name | Streptanthus carinatus | - | 2 | RT |
| No common name | streptocephalus thomasbowmani | - | 2 | SU |
| No common name | streptocephalus thomasbowmani | - | 2 | SU |
| No common name | Stylocline citroleum | - | 1 | SC |
| No common name | Stylocline masonii | - | 1 | SC |
| No common name | Styphelia tameiameiae hexamera | - | 1 | RT |
| No common name | Suaeda rolandii | - | 5 | SC |
| No common name | Sullivantia hapemanii | - | 6 | SC |
| No common name | Sullivantia oregana | - | 1 | SC |
| No common name | Sullivantia purpusii | - | 6 | RT |
| No common name | Synthyris canbyi | - | 6 | RT |
| No common name | Synthyris missurica hirsuta | - | 1 | RT |
| No common name | Synthyris missurica stellata | - | 1 | RT |
| No common name | Synthyris pinnatifida canescens | - | 1 | RT |
| No common name | Synthyris pinnatifida lanuginosa | - | 1 | RT |
| No common name | Synthyris platycarpa | - | 1 | RT |
| No common name | Synthyris schizantha | - | 1 | RT |
| No common name | Tabernaemontana rotensis | - | 1 | RT |
| No common name | Tagetes lemmonii | - | 2 | RT |
| No common name | Taraxacum carneocoloratum | - | 7 | SC |
| No common name | tartarocreagris intermedia | - | 2 | SU |
| No common name | Tauschia stricklandii | - | 1 | RT |
| No common name | Tauschia tenuissima | - | 1 | RT |
| No common name | Tectaria amesiana | - | 4 | SC |
| No common name | Tectaria estremerana | - | 4 | E |
| No common name | Teloschistes villosus | - | 1 | SC |
| No common name | Tephrosia angustissima | - | 4 | SC |
| No common name | Ternstroemia subsessilis | - | 4 | E |
| No common name | Tetramolopium arenarium | - | 1 | E |
| No common name | Tetramolopium consanguineum consanguineum | - | 1 | RT |
| No common name | Tetramolopium consanguineum leptophyllum | - | 1 | SC |
| No common name | Tetramolopium conyzoides | - | 1 | RT |
| No common name | Tetramolopium filiforme | - | 1 | E |
| No common name | Tetramolopium humile sublaeve | - | 1 | SC |
| No common name | Tetramolopium kavaiensis koloana | - | 1 | RT |
| No common name | Tetramolopium lepidotum arbusculum | - | 1 | RT |
| No common name | Tetramolopium lepidotum ssp. lepidotum | - | 1 | E |
| No common name | Tetramolopium remyi | - | 1 | E |
| No common name | Tetramolopium rockii | - | 1 | T |
| No common name | Tetramolopium tenerrimum | - | 1 | RT |
| No common name | Tetramolopius kavaiensis koloana | - | 1 | RT |
| No common name | tetraneuris verdiensis | - | 2 | SU |
| No common name | Tetraplasandra bisattenuata | - | 1 | E |
| No common name | Tetraplasandra flynnii | - | 1 | E |
| No common name | Tetraplasandra hawaiiensis hawaiiensis | - | 1 | RT |
| No common name | Tetraplasandra kahanana | - | 1 | RT |
| No common name | Tetraplasandra kohalae | - | 1 | RT |
| No common name | Tetraplasandra lanaiensis | - | 1 | RT |
| No common name | Tetraplasandra lihuensis gracilipes | - | 1 | RT |
| No common name | Tetraplasandra lydgatei | - | 1 | RT |
| No common name | Tetraplasandra meiandra bisobtusa | - | 1 | RT |
| No common name | Tetraplasandra meiandra bryanii | - | 1 | RT |
| No common name | Tetraplasandra meiandra degeneri | - | 1 | RT |
| No common name | Tetraplasandra meiandra hillebrandii | - | 1 | RT |
| No common name | Tetraplasandra meiandra hiloensis | - | 1 | RT |
| No common name | Tetraplasandra meiandra leptomera | - | 1 | RT |
| No common name | Tetraplasandra meiandra makalehana | - | 1 | RT |
| No common name | Tetraplasandra meiandra rhynchocarpoides | - | 1 | RT |
| No common name | Tetraplasandra meiandra simulans | - | 1 | RT |
| No common name | Tetraplasandra munroi | - | 1 | RT |
| No common name | Tetraplasandra oahuensis eradiata | - | 1 | RT |
| No common name | Tetraplasandra oahuensis fauriei | - | 1 | RT |
| No common name | Tetraplasandra oahuensis hailiensis | - | 1 | RT |
| No common name | Tetraplasandra oahuensis longipes | - | 1 | RT |
| No common name | Tetraplasandra oahuensis pseudorhachis | - | 1 | RT |
| No common name | Tetraplasandra pupukeensis nitida | - | 1 | RT |
| No common name | Tetraplasandra pupukeensis pupukeensis | - | 1 | RT |
| No common name | Tetraplasandra pupukeensis venosa | - | 1 | RT |
| No common name | Tetraplasandra turbans | - | 1 | RT |
| No common name | Tetraplasandra waialealae urceolata | - | 1 | RT |
| No common name | Tetraplasandra waimeae angustior | - | 1 | RT |
| No common name | texella brevidenta | - | 2 | SU |
| No common name | texella brevistyla | - | 2 | SU |
| No common name | texella diplospina | - | 2 | SU |
| No common name | texella fendi | - | 2 | SU |
| No common name | texella grubbsi | - | 2 | SU |
| No common name | texella hardeni | - | 2 | SU |
| No common name | texella renkesae | - | 2 | SU |
| No common name | texella welbourni | - | 2 | SU |
| No common name | texiweckelia relicta | - | 2 | SU |
| No common name | Thalictrum arkansanum | - | 2 | SC |
| No common name | Thalictrum debile | - | 4 | RT |
| No common name | Thalictrum heliophilum | - | 6 | RT |
| No common name | Thalictrum mirabile | - | 4 | SC |
| No common name | Thalictrum subrotundum | - | 4 | SC |
| No common name | thalkethops grallatrix | - | 2 | SU |
| No common name | Thelesperma caespitosum | - | 6 | SC |
| No common name | Thelesperma pubescens | - | 6 | SC |
| No common name | Thelesperma subnudum alpinum | - | 6 | SC |
| No common name | Thelocactus bicolor flavidispinus | - | 2 | SC |
| No common name | Thelypodium eucosmum | - | 1 | SC |
| No common name | Thelypodium laxiflorum | - | 6 | RT |
| No common name | Thelypodium sagittatum ovalifolium | - | 6 | RT |
| No common name | Thelypodium vernale | - | 2 | RT |
| No common name | Thelypteris hastata heterodoxa | - | 4 | SC |
| No common name | Thelypteris inabonensis | - | 4 | E |
| No common name | Thelypteris verecunda | - | 4 | E |
| No common name | Thelypteris yaucoensis | - | 4 | E |
| No common name | Thismia americana | - | 3 | SC |
| No common name | Thlaspi arcticum | - | 7 | RT |
| No common name | Thlaspi montanum siskiyouense | - | 1 | RT |
| No common name | thymoites minero | - | 2 | SU |
| No common name | Tithonia thurberi | - | 2 | RT |
| No common name | Tofieldia glutinosa absona | - | 1 | SC |
| No common name | Townsendia alpigena minima | - | 6 | RT |
| No common name | Townsendia jonesii tumulosa | - | 1 | SC |
| No common name | Tradescantia edwardsiana | - | 2 | RT |
| No common name | Tradescantia ozarkana | - | 4 | SC |
| No common name | Tragia nigricans | - | 2 | RT |
| No common name | Tragia saxicola | - | 4 | SC |
| No common name | Trematolobelia grandifolia | - | 1 | SC |
| No common name | Trematolobelia singularis | - | 1 | E |
| No common name | Trichomanes draytonianum | - | 1 | RT |
| No common name | Trifolium andersonii friscanum | - | 6 | SC |
| No common name | Trifolium andinum podocephalum | - | 1 | SC |
| No common name | Trillium pusillum monticulum | - | 5 | SC |
| No common name | Trillium pusillum pusillum | - | 4 | SC |
| No common name | Trisetum orthochaetum | - | 6 | RT |
| No common name | Triteleia lemmonae | - | 2 | RT |
| No common name | Triteleiopsis palmeri | - | 2 | RT |
| No common name | Trollius laxus laxus | - | 5 | RT |
| No common name | tuberochernes ubicki | - | 2 | SU |
| No common name | Urera konaensis | - | 1 | RT |
| No common name | ursia furtiva | - | 2 | SU |
| No common name | ursia species | - | 2 | SU |
| No common name | Urtica chamaedryoides | - | 2 | RT |
| No common name | Usnea longissima | - | 8 | RT |
| No common name | Vaccinium vacillans missouriense | - | 3 | RT |
| No common name | Valeriana columbiana | - | 1 | RT |
| No common name | Verbena maritima | - | 4 | SC |
| No common name | Verbesina heterophylla | - | 4 | SC |
| No common name | Vernonia borinquensis | - | 4 | SC |
| No common name | Vernonia proctorii | - | 4 | E |
| No common name | Vernonia pulchella | - | 4 | RT |
| No common name | Veronica sherwoodii | - | 1 | RT |
| No common name | Vigna o-wahuensis | - | 1 | E |
| No common name | Viguiera porteri | - | 4 | RT |
| No common name | Viola adunca cascadensis | - | 1 | RT |
| No common name | Viola egglestonii | - | 4 | RT |
| No common name | Viola helenae | - | 1 | E |
| No common name | Viola lanaiensis | - | 1 | E |
| No common name | Viola lithion | - | 6 | SC |
| No common name | Viola oahuensis | - | 1 | E |
| No common name | Viola robusta | - | 1 | RT |
| No common name | Waldsteinia idahoensis | - | 1 | RT |
| No common name | Waltheria pyrolaefolia | - | 1 | RT |
| No common name | Wikstroemia basicorda | - | 1 | RT |
| No common name | Wikstroemia hanalei | - | 1 | RT |
| No common name | Wikstroemia isae | - | 1 | RT |
| No common name | Wikstroemia leptantha | - | 1 | RT |
| No common name | Wikstroemia monticola occidentalis | - | 1 | RT |
| No common name | Wikstroemia perdita | - | 1 | RT |
| No common name | Wikstroemia skottsbergiana | - | 1 | SC |
| No common name | Wikstroemia villosa | - | 1 | SC |
| No common name | Wilkstroemia bicornuta | - | 1 | SC |
| No common name | Willkommia texana | - | 2 | RT |
| No common name | Woodsia abbeae | - | 3 | RT |
| No common name | xanthoparmelia dissensa | - | 2 | SU |
| No common name | xanthoparmelia planilobata | - | 2 | SU |
| No common name | Xylorhiza confertifolia | - | 6 | RT |
| No common name | Xylorhiza cronquistii | - | 6 | SC |
| No common name | Xylosma crenatum | - | 1 | E |
| No common name | Xyris isoetifolia | - | 4 | SC |
| No common name | Xyris scabrifolia | - | 4 | SC |
| No common name | Yucca angustissima toftiae | - | 6 | RT |
| No common name | yucca cernua | - | 2 | SU |
| No common name | Zanthoxylum glandulosum | - | 1 | RT |
| No common name | Zanthoxylum kauaense kohuana | - | 1 | RT |
| No common name | Zanthoxylum maviense | - | 1 | RT |
| No common name | Zephyranthes simpsonii | - | 4 | RT |
| No common name | Zephyranthes treatiae | - | 4 | RT |
| No common name | Zizia latifolia | - | 4 | SC |
| Noctuid moth, Annointed sallow | Pyreferra ceromatica | - | 4 | SC |
| Noctuid moth, black-veined agrotis | Agrotis melanoneura | - | 1 | SC |
| Noctuid moth, Carter's | Spartiniphaga carterae | - | 4 | SC |
| Noctuid moth, Cremata agrotis | Agrotis cremata | - | 1 | SC |
| Noctuid moth, Hebard's | Erythroecia hebardi | - | 3 | SC |
| Noctuid moth, microreas agrotis | Agrotis microreas | - | 1 | SC |
| Noctuid moth, potophila agrotis | Agrotis potophila | - | 1 | SC |
| Noctuid moth, red anomis | Anomis vulpicolor | - | 1 | SC |
| Noctuid moth, scrub golden aster | Schinia rufipenna | - | 4 | SC |
| Noctuid moth, tortoise commensal | Idia gopheri | - | 4 | SC |
| Noctuid moth, [unnamed] | Luperina trigona | - | 4 | SC |
| Noctuid moth, [unnamed] | Papaipema aerata | - | 5 | SC |
| Noctuid moth, [unnamed] | Papaipema aweme | - | 3 | SC |
| Noctuid moth, [unnamed] | Schinia indiana | - | 3 | SC |
| Noctuid, Venus flytrap | Hemipachnolia subporphyria subporphyria | - | 4 | SC |
| Nodding-caps, Craighead's | Triphora craigheadii | - | 4 | SC |
| Nodding-caps, [unnamed] | Triphora latifolia | - | 4 | SC |
| Nodding-caps, [unnamed] | Triphora rickettii | - | 4 | SC |
| Nohoanu | Geranium hanaense | - | 1 | C |
| Nohoanu | Geranium hillebrandii | - | 1 | C |
| Nohoanu | Geranium kauaiense | - | 1 | E |
| Nohoanu | Geranium multiflorum | - | 1 | E |
| None | Esenbeckia runyonii | - | 2 | RT |
| Noni kuahiwi | Morinda trimera | - | 1 | RT |
| Nukupu`u (honeycreeper) | Hemignathus lucidus | - | 1 | E |
| Numbat | Myrmecobius fasciatus | - | Foreign | E |
| Nuthatch, Algerian | Sitta ledanti | - | Foreign | E |
| nuthatch, White-breasted | sitta carolinensis ssp. aculeata | - | 6 | SC |
| Oak fern, sp. nov. ined. (Appalachian) | Gymnocarpium sp. | - | 5 | SC |
| Oak, blue | Quercus douglasii | - | NA | RT |
| Oak, Boynton's | Quercus boyntonii | - | 2 | SC |
| Oak, California black | Quercus kelloggii | - | NA | RT |
| Oak, Chisos Mountains | Quercus tardifolia | - | 2 | SC |
| oak, Engelmann | quercus engelmannii | - | 6 | SC |
| Oak, Hinckley | Quercus hinckleyi | - | 2 | T |
| Oak, island | Quercus tomentella | - | 1 | RT |
| Oak, maple-leaf | Quercus shumardii acerifolia | - | 4 | SC |
| Oak, Nuttall's scrub | Quercus dumosa | - | 1 | SC |
| Oak, Oglethorpe | Quercus oglethorpensis | - | 4 | RT |
| Oak, Santa Cruz Island | Quercus parvula | - | 1 | RT |
| oak, Scrub | Quercus berberidifolia | - | 1 | SC |
| Oak, slender | Quercus graciliformis | - | 2 | SC |
| Oak, Valley | Quercus lobata | - | NA | RT |
| Oak, [unnamed] | Quercus arkansana | - | 4 | RT |
| Oak, [unnamed] | Quercus georgiana | - | 4 | RT |
| Ocelot | Leopardus (=Felis) pardalis | - | 2 | E |
| Oconee-bells | Shortia galacifolia | - | 4 | SC |
| Oconee-bells, short-styled | Shortia galacifolia brevistyla | - | 4 | SC |
| Oha | Delissea rivularis | - | 1 | E |
| Oha | Delissea subcordata | - | 1 | E |
| Ohai | Sesbania tomentosa | - | 1 | E |
| Olaga | Opuntia borinquensis | - | 4 | RT |
| Olapa, [unnamed] | Cheirodendron trigynum rockii | - | 1 | RT |
| Olapa, [unnamed] | Cheirodendron trigynum subcordatum | - | 1 | RT |
| Old man's beard | Clematis micrantha | - | 4 | RT |
| Olulu | Brighamia insignis | - | 1 | E |
| Onion, Aase's | Allium aaseae | - | 1 | SC |
| Onion, Beegum | Allium hoffmanii | - | 1 | RT |
| Onion, Blue Mountain | Allium dictuon | - | 1 | SC |
| Onion, Goodding's | Allium gooddingii | - | 2 | RT |
| Onion, Hickman's | Allium hickmanii | - | 1 | SC |
| Onion, Howell's | Allium pleianthum | - | 1 | RT |
| Onion, Jepson's | Allium jepsoni | - | 1 | SC |
| Onion, Munz's | Allium munzii | - | 8 | E |
| Onion, Passey's | Allium passeyi | - | 6 | SC |
| Onion, Rawhide Hill | Allium tuolumnense | - | 1 | RT |
| Onion, Siskiyou | Allium tribracteatum | - | 1 | SC |
| Onion, Spanish needle | Allium shevockii | - | 1 | SC |
| Onion, Yosemite | Allium yosemitense | - | 1 | RT |
| onion, Yucaipa | allium haematochiton | - | 6 | SC |
| Onion, [unnamed] | Allium constrictum | - | 1 | RT |
| Onion, [unnamed] | Allium madidum | - | 1 | RT |
| Onion, [unnamed] | Allium oxyphilum | - | 5 | RT |
| Onion, [unnamed] | Allium perdulce sperryi | - | 2 | RT |
| Onion, [unnamed] | Allium robinsonii | - | 1 | RT |
| Onion, [unnamed] | Allium scilloides | - | 1 | RT |
| Onion, [unnamed] | Allium speculae | - | 4 | SC |
| Onion, [unnamed] | Allium tolmiei persimile | - | 1 | RT |
| Opuhe | Urera kaalae | - | 1 | E |
| Orangutan | Pongo pygmaeus | - | Foreign | E |
| Orchid, dollar | Encyclia boothiana erythronioides | - | 4 | RT |
| Orchid, eastern prairie fringed | Platanthera leucophaea | - | 3 | T |
| Orchid, purple fringeless | Platanthera peramoena | - | 4 | RT |
| Orchid, tiny | Lepanthopsis melanantha | - | 4 | SC |
| Orchid, western prairie fringed | Platanthera praeclara | - | 3 | T |
| Orchid, white fringeless | Platanthera integrilabia | - | 4 | C |
| Orcutt grass, California | Orcuttia californica | - | 8 | E |
| Orcutt grass, hairy | Orcuttia pilosa | - | 8 | E |
| Orcutt grass, Sacramento | Orcuttia viscida | - | 8 | E |
| Orcutt grass, San Joaquin | Orcuttia inaequalis | - | 8 | T |
| Orcutt grass, slender | Orcuttia tenuis | - | 8 | T |
| Oreganillo | Eupatorium droserolepis | - | 4 | SC |
| Oregonian Kingston | Cryptomastix sanburni | - | 6 | SC |
| Oregonian, Columbia | Cryptomastix hendersoni | - | 1 | SU |
| Oregonian, Mission Creek | Cryptomastix magnidentata | - | 1 | SC |
| oregonian, Puget | Cryptomastix devia | - | 1 | SU |
| Oriole, Audubon's | Icterus graduacauda audubonii | - | 2 | SC |
| Oriole, Mexican hooded | Icterus cucullatus cucullatus | - | 2 | SC |
| Oriole, Sennett's hooded | Icterus cucullatus sennetti | - | 2 | SC |
| Orthocarpus, San Bernardino Mountains | Castilleja lasiorhyncha | - | 1 | SC |
| Orthocarpus, Shasta | Orthocarpus pachystachyus | - | 1 | RT |
| Oryctes, Nevada | Oryctes nevadensis | - | 1 | SC |
| Oryx, Arabian | Oryx leucoryx | - | Foreign | E |
| Oryx, scimitar-horned | Oryx dammah | - | Foreign | E |
| osprey | pandion haliaetus | - | 6 | SC |
| Ostracod, Grayson crayfish | Ascetocthere cosmeta | - | 4 | SC |
| Ostracod, Oconee crayfish | Cymocythere clavata | - | 4 | SC |
| Ostracod, whitewater crayfish | Dactylocythere prinsi | - | 4 | SC |
| Ostracod, [unnamed] | Dactylocythere isabelae | - | 4 | SC |
| Ostracod, [unnamed] | Dactylocythere peedeensis | - | 4 | SC |
| Ostracod, [unnamed] | Waltoncythere acuta | - | 4 | SC |
| Ostrich, Arabian | Struthio camelus syriacus | - | Foreign | E |
| Ostrich, West African | Struthio camelus spatzi | - | Foreign | E |
| Otter, Cameroon clawless | Aonyx congicus (=congica) microdon | - | Foreign | E |
| Otter, giant | Pteronura brasiliensis | - | Foreign | E |
| Otter, long-tailed | Lontra (=Lutra) longicaudis (incl. platensis) | - | Foreign | E |
| Otter, marine | Lontra (=Lutra) felina | - | Foreign | E |
| Otter, Northern Sea | Enhydra lutris kenyoni | southwest Alaska DPS (Aleutian Islands, Alaska Peninsula coast, and Kodiak Archipelago) | 7 | T |
| Otter, river | Lutra canadensis | - | 9 | RT |
| Otter, southern river | Lontra (=Lutra) provocax | - | Foreign | E |
| Otter, southern sea | Enhydra lutris nereis | Entire, except where listed below | 8 | T |
| Otter, southern sea | Enhydra lutris nereis | All areas subject to U.S. jurisdiction south of Pt. Conception, CA (34026.9' N. Lat.) [Note--status governed by Pub. L. 99-625, 100 Stat. 3500.] | 8 | EXPN |
| Otter, southwestern | Lutra canadensis sonora | - | 2 | SC |
| Oval, Calico Rock | Mesodon clenchi | - | 4 | SC |
| Owl's clover, Humboldt Bay | Castilleja ambigua humboldtiensis | - | 1 | SC |
| Owl's-clover, fleshy | Castilleja campestris ssp. succulenta | - | 8 | T |
| Owl's-clover, San Francisco | Triphysaria floribunda | - | 1 | SC |
| Owl, Anjouan scops | Otus rutilus capnodes | - | Foreign | E |
| Owl, California spotted | Strix occidentalis occidentalis | entire | 8 | RT |
| owl, Elf | micrathene whitneyi | - | 6 | SC |
| Owl, Flammulated | Otus flammeolus | - | 1 | SU |
| Owl, giant scops | Mimizuku (=Otus) gurneyi | - | Foreign | E |
| Owl, grass | Tyto longimembris | - | Foreign | UR |
| Owl, Hawaiian short-eared | Asio flammeus sandwichensis | - | 1 | SC |
| Owl, Lanyu Scops | Otus elegans botelensis | - | Foreign | UR |
| owl, Long-eared | asio otus | - | 7 | SC |
| Owl, Madagascar red | Tyto soumagnei | - | Foreign | E |
| Owl, Mexican spotted | Strix occidentalis lucida | - | 2 | T |
| Owl, northern spotted | Strix occidentalis caurina | - | 1 | T |
| Owl, Palau | Pyrroglaux podargina | - | Foreign | DM |
| Owl, Ponape short-eared | Asio flammeus ponapensis | - | Foreign | Unlist |
| Owl, Seychelles scops | Otus magicus (=insularis) insularis | - | Foreign | E |
| Owl, Virgin Islands screech | Otus nudipes newtoni | - | 4 | SC |
| Owl, western burrowing | Athene cunicularia hypugea | - | 1 | SC |
| Owlet, Morden's | Otus ireneae | - | Foreign | E |
| oxytheca, chickweed | Oxytheca caryophylloides | - | 1 | SC |
| Oxytheca, Cienega Seca | Oxytheca parishii ciengensis | - | 1 | SC |
| Oxytheca, cushenbury | Oxytheca parishii var. goodmaniana | - | 8 | E |
| Oxytrope, Kokrines | Oxytropis kokrinensis | - | 7 | RT |
| Oystercatcher, american | Haematopus palliatus | - | 4 | SC |
| Oystercatcher, Canarian black | Haematopus meadewaldoi | - | Foreign | E |
| Oystercatcher, Chatham Island | Haematopus chathamensis | - | Foreign | UR |
| O`opu alamo`o | Lentipes concolor | - | 1 | SC |
| Paddlefish | Polyodon spathula | - | 3 | RT |
| Paintbrush, Aquarius | Castilleja aquariensis | - | 6 | RT |
| Paintbrush, ash-grey | Castilleja cinerea | - | 8 | T |
| Paintbrush, Christ's | Castilleja christii | - | 1 | C |
| paintbrush, Clokey | castilleja applegatei ssp. martinii var. clokeyi | - | 6 | SC |
| Paintbrush, common Wallowa | Castilleja ownbeyana | - | 1 | RT |
| Paintbrush, Culbertson's | Castilleja culbertsonii | - | 1 | RT |
| Paintbrush, Ewan's | Castilleja martinii ewanii | - | 1 | RT |
| Paintbrush, golden | Castilleja levisecta | - | 1 | T |
| Paintbrush, green-tinged | Castilleja chlorotica | - | 1 | SC |
| Paintbrush, Kaibab | Castilleja kaibabensis | - | 2 | RT |
| Paintbrush, Lemmon's | Castilleja lassenensis | - | 1 | RT |
| Paintbrush, Mendocino coast | Castilleja mendocinensis | - | 1 | SC |
| Paintbrush, Monte Neva | Castilleja salsuginosa | - | 8 | SC |
| Paintbrush, Mt. Gleason | Castilleja gleasonii | - | 1 | SC |
| Paintbrush, Obscure Indian | Castilleja cryptantha | - | 1 | SC |
| Paintbrush, Pitkin Marsh | Castilleja uliginosa | - | 1 | SC |
| Paintbrush, Point Reyes | Castilleja leschkeana | - | 1 | RT |
| Paintbrush, short-lobed | Castilleja brevilobata | - | 1 | RT |
| Paintbrush, Siskiyou | Castilleja elata | - | 1 | RT |
| Paintbrush, soft-leaved | Castilleja mollis | - | 8 | E |
| Paintbrush, Steen's mountain | Castilleja pilosa steenensis | - | 1 | SC |
| Paintbrush, tall | Castilleja elongata | - | 2 | RT |
| Paintbrush, Tiburon | Castilleja affinis ssp. neglecta | - | 8 | E |
| Paintbrush, White Mountains | Castilleja mogollonica | - | 2 | SC |
| Paintbrush, white-felted | Castilleja hololeuca | - | 1 | RT |
| Palila (honeycreeper) | Loxioides bailleui | - | 1 | E |
| Palm, needle | Rhapidophyllum hystrix | - | 4 | RT |
| Palm, royal, Florida | Roystonea elata | - | 4 | RT |
| Palmetto, Miami | Sabal miamiensis | - | 4 | RT |
| Palo colorado | Ternstroemia luquillensis | - | 4 | E |
| Palo de jazmin | Styrax portoricensis | - | 4 | E |
| Palo de nigua | Cornutia obovata | - | 4 | E |
| Palo de ramon | Banara vanderbiltii | - | 4 | E |
| Palo de rosa | Ottoschulzia rhodoxylon | - | 4 | E |
| Palo de violeta | Polygala cowellii | - | 4 | RT |
| Pamakani | Tetramolopium capillare | - | 1 | E |
| Pamakani | Viola chamissoniana ssp. chamissoniana | - | 1 | E |
| panaunau | lobelia yuccoides | - | 1 | SC |
| Panda, giant | Ailuropoda melanoleuca | - | Foreign | E |
| Pangolin, Temnick's ground | Manis temminckii | - | Foreign | E |
| Panic grass, Faurie's | Panicum fauriei fauriei | - | 1 | RT |
| Panic grass, Fernald's | Panicum mundum | - | 5 | RT |
| Panic grass, Hirsts' | Dichanthelium (=Panicum) hirstii | - | 5 | C |
| Panic grass, Shasta | Panicum shastense | - | 1 | RT |
| Panic grass, Sonoran | Panicum sonoran | - | NA | SU |
| Panic grass, The Geysers | Dichanthelium lanuginosum thermale | - | 1 | SC |
| Panic grass, [unnamed] | Panicum aculeatum | - | 5 | RT |
| Panic grass, [unnamed] | Panicum alakaiense | - | 1 | RT |
| Panic grass, [unnamed] | Panicum lamiatile | - | 1 | RT |
| Panic grass, [unnamed] | Panicum lustriale | - | 1 | RT |
| Panicgrass, Carter's | Panicum fauriei var. carteri | - | 1 | E |
| Panther, Florida | Puma (=Felis) concolor coryi | - | 4 | E |
| Papala | Charpentiera densiflora | - | 1 | E |
| Papershell, Cumberland | Anodontoides denigrata | - | 4 | SC |
| Papillosus, small | Echinocereus papillosus angusticeps | - | 2 | SC |
| Parakeet, blue-throated (=ochre-marked) | Pyrrhura cruentata | - | Foreign | E |
| Parakeet, Forbes' | Cyanoramphus auriceps forbesi | - | Foreign | E |
| Parakeet, golden | Aratinga guarouba | - | Foreign | E |
| Parakeet, golden-shouldered | Psephotus chrysopterygius | - | Foreign | E |
| Parakeet, grey-cheeked | Brotogeris pyrrhoptera | - | Foreign | UR |
| Parakeet, Mauritius | Psittacula echo | - | Foreign | E |
| Parakeet, Norfolk Island | Cyanoramphus cookii (=novaezelandiae c.) | - | Foreign | E |
| Parakeet, orange-bellied | Neophema chrysogaster | - | Foreign | E |
| Parakeet, orange-fronted | Cyanoramphus malherbi | - | Foreign | UR |
| Parakeet, paradise | Psephotus pulcherrimus | - | Foreign | E |
| Parakeet, scarlet-chested | Neophema splendida | - | Foreign | E |
| Parakeet, turquoise | Neophema pulchella | - | Foreign | E |
| Parakeet, Uvea | Eunymphicus uveaensis | - | Foreign | UR |
| Parnassian, Strohbeen's | Parnassius clodius strohbeeni | - | 1 | RT |
| Parrot, Bahaman or Cuban | Amazona leucocephala | - | Foreign | E |
| Parrot, crimson shining | Prosopeia splendens | - | Foreign | UR |
| Parrot, ground | Pezoporus wallicus | - | Foreign | E |
| Parrot, imperial | Amazona imperialis | - | Foreign | E |
| Parrot, night (=Australian) | Geopsittacus occidentalis | - | Foreign | E |
| Parrot, Puerto Rican | Amazona vittata | - | 4 | E |
| Parrot, red-browed | Amazona rhodocorytha | - | Foreign | E |
| Parrot, red-capped | Pionopsitta pileata | - | Foreign | E |
| Parrot, red-crowned | Amazona viridigenalis | - | Foreign | UR |
| Parrot, red-necked | Amazona arausiaca | - | Foreign | E |
| Parrot, red-spectacled | Amazona pretrei pretrei | - | Foreign | E |
| Parrot, red-tailed | Amazona brasiliensis | - | Foreign | E |
| Parrot, Seychelles lesser vasa | Coracopsis nigra barklyi | - | Foreign | E |
| Parrot, St Vincent | Amazona guildingii | - | Foreign | E |
| Parrot, St. Lucia | Amazona versicolor | - | Foreign | E |
| Parrot, thick-billed | Rhynchopsitta pachyrhyncha | Mexico | Foreign | E |
| Parrot, vinaceous-breasted | Amazona vinacea | - | Foreign | E |
| Parrot, yellow-billed | Amazona collaria | - | Foreign | UR |
| Parrotbill, Maui (honeycreeper) | Pseudonestor xanthophrys | - | 1 | E |
| Parrotfinch, Palau blue-faced | Erythrura trichroa pelewensis | - | 1 | RT |
| Parrya, Rydberg | Parrya rydbergii | - | 6 | RT |
| parsley Pikes Peak Spring | Oreoxis humilis | - | 6 | SC |
| Parsley, hemlock, Mexican | Conioselinum mexicanum | - | 2 | SC |
| Partridge, Italian grey | Perdix perdix italica | - | Foreign | UR |
| Parula, tropical | Parula pitiayumi nigrilora | - | 2 | SC |
| Pauoa | Ctenitis squamigera | - | 1 | E |
| Pawpaw, beautiful | Deeringothamnus pulchellus | - | 4 | E |
| Pawpaw, four-petal | Asimina tetramera | - | 4 | E |
| Pawpaw, Rugel's | Deeringothamnus rugelii | - | 4 | E |
| Pa`iniu | Astelia veratroides gracilis | - | 1 | RT |
| Pa`iniu | Astelia veratroides macrosperma | - | 1 | RT |
| Pa`iniu | Astelia veratroides veratroides | - | 1 | RT |
| Pa`iniu | Astelia waialealae | - | 1 | E |
| Pea, Big Pine partridge | Chamaecrista lineata keyensis | - | 4 | C |
| Pea, Torrey's | Lathyrus torreyi | - | 1 | SC |
| Peaclam, Sangre de Cristo | Pisidium sanquinichristi | - | 2 | SC |
| Peaclam, [unnamed] | Pisidium ultramontanum | - | 1 | RT |
| Pearlshell, Alabama | Margaritifera marrianae | - | 4 | C |
| Pearlshell, Louisiana | Margaritifera hembeli | - | 4 | T |
| Pearlymussel, birdwing | Conradilla caelata | U.S.A. (AL;The free-flowing reach of the Tennessee R. from the base of Wilson Dam downstream to the backwaters of Pickwick Reservoir [about 12 RM (19 km)] and the lower 5 RM [8 km] of all tributaries to this reach in Colbert and Lauderdale Cos., see 17.85(a)) | 4 | EXPN |
| Pearlymussel, birdwing | Conradilla caelata | Entire Range; Except where listed as Experimental Populations | 4 | E |
| Pearlymussel, birdwing | Conradilla caelata | U.S.A. (TN - specified portions of the French Broad and Holston Rivers; see 17.85(b)(1)) | 4 | EXPN |
| Pearlymussel, cracking | Hemistena lata | U.S.A. (AL;The free-flowing reach of the Tennessee R. from the base of Wilson Dam downstream to the backwaters of Pickwick Reservoir [about 12 RM (19 km)] and the lower 5 RM [8 km] of all tributaries to this reach in Colbert and Lauderdale Cos., see 17.85(a)) | 4 | EXPN |
| Pearlymussel, cracking | Hemistena lata | Entire Range; Except where listed as Experimental Populations | 4 | E |
| Pearlymussel, cracking | Hemistena lata | U.S.A. (TN - specified portions of the French Broad and Holston Rivers; see 17.85(b)(1)) | 4 | EXPN |
| Pearlymussel, Curtis | Epioblasma florentina curtisii | - | 3 | E |
| Pearlymussel, dromedary | Dromus dromas | U.S.A. (AL;The free-flowing reach of the Tennessee R. from the base of Wilson Dam downstream to the backwaters of Pickwick Reservoir [about 12 RM (19 km)] and the lower 5 RM [8 km] of all tributaries to this reach in Colbert and Lauderdale Cos., see 17.85(a)) | 4 | EXPN |
| Pearlymussel, dromedary | Dromus dromas | Entire Range; Except where listed as Experimental Populations | 4 | E |
| Pearlymussel, dromedary | Dromus dromas | U.S.A. (TN - specified portions of the French Broad and Holston Rivers; see 17.85(b)(1)) | 4 | EXPN |
| Pearlymussel, littlewing | Pegias fabula | - | 4 | E |
| Pearlymussel, Nicklin's | Megalonaias nicklineana | - | Foreign | E |
| Pearlymussel, Sampson's | Epioblasma sampsoni | - | 3 | D3A |
| Pearlymussel, slabside | Lexingtonia dolabelloides | - | 4 | C |
| Pearlymussel, Tampico | Cyrtonaias tampicoensis tecomatensis | - | Foreign | E |
| Pebblesnail, angular | Somatogyrus biangulatus | - | 4 | SC |
| Pebblesnail, Ash Meadows | Pyrgulopsis erythropoma | - | 8 | UR |
| Pebblesnail, Atlas | Somatogyrus humerosus | - | 4 | SC |
| Pebblesnail, Cahaba | Clappia cahabensis | - | 4 | RT |
| Pebblesnail, Cahaba | Clappia umbilicata | - | 4 | RT |
| Pebblesnail, channeled | Somatogyrus wheeleri | - | 4 | SC |
| Pebblesnail, Columbia | Fluminicola columbianus | - | 1 | RT |
| Pebblesnail, Coosa | Somatogyrus coosaensis | - | 4 | SC |
| Pebblesnail, Diminuitive | Fluminicola sp | - | 1 | SU |
| Pebblesnail, Disjunct | Fluminicola spg | - | 8 | SU |
| Pebblesnail, dwarf | Somatogyrus nanus | - | 4 | SC |
| Pebblesnail, flat | Lepyrium showalteri | - | 4 | E |
| Pebblesnail, Flat-top | Fluminicola spe | - | 8 | SU |
| Pebblesnail, fluted | Somatogyrus hendersoni | - | 4 | SC |
| Pebblesnail, globular | Fluminicola sph | - | 8 | SU |
| Pebblesnail, golden | Somatogyrus aureus | - | 4 | SC |
| Pebblesnail, granite | Somatogyrus hinkleyi | - | 4 | SC |
| Pebblesnail, hidden | Somatogyrus deciphens | - | 4 | SC |
| Pebblesnail, knotty | Somatogyrus constrictus | - | 4 | SC |
| Pebblesnail, Lost Creek | Fluminicola spj | - | 8 | SU |
| Pebblesnail, Moapa | Pyrgulopsis avernalis | - | 8 | UR |
| Pebblesnail, moon | Somatogyrus obtusus | - | 4 | SC |
| Pebblesnail, mud | Somatogyrus sargenti | - | 4 | SC |
| Pebblesnail, Nerite | Fluminicola spc | - | 1 | SU |
| Pebblesnail, nugget | Fluminicola seminalis | - | 8 | SU |
| Pebblesnail, Oachita | Somatogyrus amnicoloides | - | 4 | SC |
| Pebblesnail, opaque | Somatogyrus tennesseensis | - | 4 | SC |
| Pebblesnail, ovate | Somatogyrus excavatus | - | 4 | SC |
| Pebblesnail, Pahranagat | Pyrgulopsis merriami | - | 8 | UR |
| Pebblesnail, Panhandle | Somatogyrus virginicus | - | 4 | SC |
| Pebblesnail, Potem | Fluminicola spd | - | 8 | SU |
| Pebblesnail, pygmy | Somatogyrus pygmaeus | - | 4 | SC |
| Pebblesnail, quadrate | Somatogyrus quadratus | - | 4 | SC |
| Pebblesnail, rolling | Somatogyrus strengi | - | 4 | SC |
| Pebblesnail, Savannah | Somatogyrus tenax | - | 4 | SC |
| Pebblesnail, Shasta Springs | Fluminicola spf | - | 8 | SU |
| Pebblesnail, sparrow | Somatogyrus parvulus | - | 4 | SC |
| Pebblesnail, stocky | Somatogyrus crassus | - | 4 | SC |
| Pebblesnail, tall | Fluminicola spk | - | 1 | SU |
| Pebblesnail, Tallapoosa | Somatogyrus pilsbryanus | - | 4 | SC |
| Pebblesnail, Tennessee | Somatogyrus currierianus | - | 4 | SC |
| Pebblesnail, thick-lipped | Somatogyrus crassilabris | - | 4 | SC |
| Pebblesnail, umbilicate | Fluminicola spi | - | 8 | SU |
| pelican, American white | pelecanus erythrorhynchos | - | 7 | SC |
| Pelican, brown | Pelecanus occidentalis | Entire, except U.S. Atlantic coast, FL, AL | 8 | DM |
| Pelican, brown | Pelecanus occidentalis | U.S. Atlantic coast, FL, AL | 4 | DM |
| pelican, Brown | pelecanus occidentalis ssp. occidentalis | - | 6 | SC |
| Pelos del diablo | Aristida portoricensis | - | 4 | E |
| penguin, African | Spheniscus demersus | - | Foreign | PE |
| penguin, eastern rockhopper | Eudyptes chrysocome filholi | - | Foreign | RT |
| penguin, emperor | Aptenodytes forsteri | - | Foreign | RT |
| penguin, erect-crested | Eudyptes sclateri | - | Foreign | PT |
| penguin, fiordland crested | Eudyptes pachyrhynchus | - | Foreign | PT |
| Penguin, Galapagos | Spheniscus mendiculus | - | Foreign | E |
| penguin, Humboldt | Spheniscus humboldti | - | Foreign | PT |
| penguin, macaroni | Eudyptes chrysolophus | Campbell Plateau portion of New Zealand/Australia population | Foreign | PT |
| penguin, northern rockhopper | Eudyptes moseleyi | - | Foreign | RT |
| penguin, royal | Eudyptes schlegeli | - | Foreign | RT |
| penguin, snares crested | Eudyptes robustus | - | Foreign | RT |
| penguin, southern rockhopper | Eudyptes chrysocome | - | Foreign | PT |
| penguin, white-flippered | Eudyptula albosignata | - | Foreign | PT |
| penguin, yellow-eyed | Megadyptes antipodes | - | Foreign | PT |
| Penny-cress, Kneeland Prairie | Thlaspi californicum | - | 8 | E |
| Pennyroyal, Flagstaff | Hedeoma diffusum | - | 2 | RT |
| Pennyroyal, Mckittrick | Hedeoma apiculatum | - | 2 | DP |
| Pennyroyal, mock | Hedeoma graveolens | - | 4 | SC |
| Pennyroyal, Old Blue mock | Hedeoma pilosum | - | 2 | SC |
| Pennyroyal, Todsen's | Hedeoma todsenii | - | 2 | E |
| Penstemon, Amargosa | Penstemon fruticiformis amargosae | - | 1 | SC |
| Penstemon, ash | Penstemon cinicola | - | 1 | RT |
| Penstemon, blowout | Penstemon haydenii | - | 6 | E |
| Penstemon, California | Penstemon californicus | - | 1 | RT |
| Penstemon, Idaho | Penstemon idahoensis | - | 1 | SC |
| Penstemon, Inyo | Penstemon papillatus | - | 1 | RT |
| Penstemon, limestone | Penstemon calcareus | - | 1 | RT |
| Penstemon, thread-leaved | Penstemon filiformis | - | 1 | SC |
| Penstemon, white-margined | Penstemon albomarginatus | - | 1 | SC |
| Pentachaeta, Lyon's | Pentachaeta lyonii | - | 8 | E |
| Pentachaeta, slender | Pentachaeta exilis aeolica | - | 1 | SC |
| Pentachaeta, white-rayed | Pentachaeta bellidiflora | - | 8 | E |
| Peperomia, Wheeler's | Peperomia wheeleri | - | 4 | E |
| Pepper cress, Davis' | Lepidium davisii | - | 1 | SC |
| Pepper-grass, Heckard's Dwarf | Lepidium latipes var. heckardii | - | 1 | SU |
| pepper-grass, Robinson's | lepidium virginicum var. robinsonii | - | 2 | SC |
| Peppergrass, Borrego Valley | Lepidium flavum felipense | - | 1 | SC |
| Peppergrass, Jared's | Lepidium jaredii jaredii | - | 1 | SC |
| Peppergrass, kodachrome | Lepidium montanum stellae | - | 6 | RT |
| Peppergrass, Panoche | Lepidium jaredii album | - | 1 | SC |
| Peppergrass, Slick spot | Lepidium papilliferum | - | 1 | T |
| Pepperwort Huber's | Lepidium huberi | - | 6 | SC |
| Pepperwort Thickleaf | Lepidium integrifolium | - | 6 | SC |
| Perch, Sacramento | Archoplites interruptus | - | 1 | SC |
| Petrel, Beck's | Pterodroma becki | - | NA | SU |
| Petrel, black-capped | Pterodroma hasitata | - | 4 | SC |
| Petrel, Chatham Island | Pterodroma axillaris | - | Foreign | E |
| Petrel, Cook's | Pterodroma cookii | - | Foreign | PT |
| Petrel, Fiji | Pterodroma macgillivrayi | - | Foreign | E |
| Petrel, Galapagos | Pterodroma phaeopygia | - | Foreign | T |
| Petrel, Hawaiian dark-rumped | Pterodroma phaeopygia sandwichensis | - | 1 | E |
| Petrel, Magenta | Pterodroma magentae | - | Foreign | E |
| Petrel, Mascarene black | Pterodroma aterrima | - | Foreign | E |
| Petrel, Parkinson's black | Procellaria parkinsoni | - | Foreign | UR |
| Phacelia, ashy | Phacelia cinerea | - | 1 | SC |
| Phacelia, Aven Nelson's | Phacelia anelsonii | - | 1 | RT |
| Phacelia, Beatley | Phacelia beatleyae | - | 1 | SC |
| Phacelia, Brand's | Phacelia stellaris | - | 8 | C |
| Phacelia, Charlotte's | Phacelia nashiana | - | 1 | SC |
| Phacelia, cinder | Phacelia serrata | - | 2 | SC |
| Phacelia, clay | Phacelia argillacea | - | 6 | E |
| Phacelia, Cooke's | Phacelia cookei | - | 1 | SC |
| Phacelia, DeBeque | Phacelia submutica | - | 6 | PT |
| Phacelia, drab | Phacelia indecora | - | 6 | RT |
| Phacelia, Howell | Phacelia howelliana | - | 6 | RT |
| Phacelia, island | Phacelia insularis ssp. insularis | - | 8 | E |
| Phacelia, Merced | Phacelia ciliata opaca | - | 1 | SC |
| Phacelia, Mono | Phacelia monoensis | - | 1 | SC |
| Phacelia, mountain | Phacelia orogenes | - | 1 | RT |
| Phacelia, Mt. Diablo | Phacelia phacelioides | - | 1 | SC |
| Phacelia, Nine Mile Canyon | Phacelia novenmillensis | - | 1 | SC |
| Phacelia, Nipple Bench | Phacelia mammillarensis | - | 6 | RT |
| Phacelia, North Park | Phacelia formosula | - | 6 | E |
| Phacelia, northcoast | Phacelia insularis continentis | - | 1 | SC |
| Phacelia, pale | Phacelia pallida | - | 2 | SC |
| Phacelia, Parish's | Phacelia parishii | - | 1 | SC |
| Phacelia, round leaf, Death Valley | Phacelia mustelina | - | 1 | RT |
| Phacelia, Saline Valley | Phacelia amabilis | - | 1 | SC |
| Phacelia, sand dune | Phacelia argentea | - | 1 | SC |
| Phacelia, Santiago Peak | Phacelia suaveolens keckii | - | 1 | SC |
| Phacelia, Scott Valley | Phacelia greenei | - | 1 | SC |
| Phacelia, southern island | Phacelia floribunda | - | 1 | SC |
| Phacelia, Stebbins' | Phacelia stebbinsii | - | 1 | SC |
| Phacelia, sticky | Phacelia lenta | - | 1 | SC |
| Phacelia, Trinity | Phacelia dalesiana | - | 1 | SC |
| Phacelia, Utah | Phacelia utahensis | - | 6 | SC |
| Phacelia, virgin | Phacelia cephalotes | - | 6 | RT |
| Phacelia, Welsh | Phacelia welshii | - | 2 | SC |
| Phacelia, [unnamed] | Phacelia capitata | - | 1 | RT |
| Phacelia, [unnamed] | Phacelia demissa heterotricha | - | 6 | RT |
| Phacelia, [unnamed] | Phacelia filiformis | - | 2 | RT |
| Phacelia, [unnamed] | Phacelia minutissima | - | 1 | SC |
| Phacelia, [unnamed] | Phacelia rafaelensis | - | 6 | RT |
| phainopepla | phainopepla nitens | - | 6 | SC |
| Pheasant, bar-tailed | Syrmaticus humaie | - | Foreign | E |
| Pheasant, Blyth's tragopan | Tragopan blythii | - | Foreign | E |
| Pheasant, brown eared | Crossoptilon mantchuricum | - | Foreign | E |
| Pheasant, Cabot's tragopan | Tragopan caboti | - | Foreign | E |
| Pheasant, cheer | Catreus wallichii | - | Foreign | E |
| Pheasant, Chinese monal | Lophophorus lhuysii | - | Foreign | E |
| Pheasant, Edward's | Lophura edwardsi | - | Foreign | E |
| Pheasant, Elliot's | Syrmaticus ellioti | - | Foreign | E |
| Pheasant, imperial | Lophura imperialis | - | Foreign | E |
| Pheasant, Mikado | Syrmaticus mikado | - | Foreign | E |
| Pheasant, Palawan peacock | Polyplectron emphanum | - | Foreign | E |
| Pheasant, Sclater's monal | Lophophorus sclateri | - | Foreign | E |
| Pheasant, Swinhoe's | Lophura swinhoii | - | Foreign | E |
| Pheasant, western tragopan | Tragopan melanocephalus | - | Foreign | E |
| Pheasant, white eared | Crossoptilon crossoptilon | - | Foreign | E |
| Phlox, Bear Valley | Phlox dolichantha | - | 1 | SC |
| Phlox, Clearwater | Phlox idahonis | - | 1 | SC |
| Phlox, cleft, | Phlox bifida stellaria | - | 3 | SC |
| Phlox, long-haired | Phlox pilosa longipilosa | - | 2 | RT |
| Phlox, Navajo Mountain | Phlox cluteana | - | 2 | RT |
| Phlox, Oklahoma | Phlox oklahomensis | - | 2 | RT |
| Phlox, Red Canyon | Phlox gladiformis | - | 1 | RT |
| Phlox, Texas trailing | Phlox nivalis ssp. texensis | - | 2 | E |
| Phlox, Yreka | Phlox hirsuta | - | 8 | E |
| Phlox, [unnamed] | Phlox caryophylla | - | 2 | RT |
| Phlox, [unnamed] | Phlox grahamii | - | 6 | RT |
| Phlox, [unnamed] | Phlox jonesii | - | 6 | RT |
| Phlox, [unnamed] | Phlox missoulensis | - | 6 | RT |
| Phlox, [unnamed] | Phlox mollis | - | 1 | RT |
| Phlox, [unnamed] | Phlox pulchra | - | 4 | RT |
| Phlox, [unnamed] | Phlox pungens | - | 6 | SC |
| Phyllostegia, Yamaguchi | Phyllostegia yamaguchii | - | 1 | RT |
| Physa, cave | Physella spelunca | - | 6 | SC |
| Physa, Fish Lake | Physella microstriata | - | 6 | SC |
| Physa, Utah | Physella utahensis | - | 6 | SC |
| Physa, wet-rock | Physella zionis | - | 6 | SC |
| Pigeon wings | Clitoria fragrans | - | 4 | T |
| Pigeon, Azores wood | Columba palumbus azorica | - | Foreign | E |
| pigeon, Band-tailed | patagioenas fasciata | - | 1 | SC |
| Pigeon, Chatham Island | Hemiphaga novaeseelandiae chathamensis | - | Foreign | E |
| Pigeon, Marquesas | Ducula galeata | - | Foreign | PE |
| Pigeon, Mindoro imperial (=zone-tailed) | Ducula mindorensis | - | Foreign | E |
| Pigeon, Palau Nicobar | Caloenas nicobarensis pelewensis | - | 1 | RT |
| Pigeon, pink | Columba mayeri | - | Foreign | E |
| Pigeon, Puerto Rican plain | Columba inornata wetmorei | - | 4 | E |
| Pigeon, Radak Micronesian | Ducula oceanica ratakensis | - | Foreign | SU |
| Pigeon, Truk Micronesian | Ducula oceanica teraoki | - | Foreign | SU |
| Pigeon, white-crowned | Columba leucocephala | - | 4 | SC |
| Pigeon, white-tailed laurel | Columba junoniae | - | Foreign | T |
| Pigtoe, Atlantic | Fusconaia masoni | - | 4 | SC |
| Pigtoe, Cumberland | Pleurobema gibberum | - | 4 | E |
| Pigtoe, dark | Pleurobema furvum | - | 4 | E |
| Pigtoe, finerayed | Fusconaia cuneolus | Entire Range; Except where listed as Experimental Populations | 4 | E |
| Pigtoe, finerayed | Fusconaia cuneolus | U.S.A. (TN - specified portions of the French Broad and Holston Rivers; see 17.85(b)(1)) | 4 | EXPN |
| Pigtoe, finerayed | Fusconaia cuneolus | U.S.A. (AL;The free-flowing reach of the Tennessee R. from the base of Wilson Dam downstream to the backwaters of Pickwick Reservoir [about 12 RM (19 km)] and the lower 5 RM [8 km] of all tributaries to this reach in Colbert and Lauderdale Cos., see 17.85(a)) | 4 | EXPN |
| Pigtoe, flat | Pleurobema marshalli | - | 4 | E |
| Pigtoe, fuzzy | Pleurobema strodeanum | - | 4 | C |
| Pigtoe, Georgia | Pleurobema hanleyianum | - | 4 | PE |
| Pigtoe, heavy | Pleurobema taitianum | - | 4 | E |
| Pigtoe, narrow | Fusconaia escambia | - | 4 | C |
| Pigtoe, oval | Pleurobema pyriforme | - | 4 | E |
| Pigtoe, pink | Pleurobema pyramidatum | - | 4 | SC |
| Pigtoe, pink | Pleurobema rubrum | - | 4 | RT |
| Pigtoe, rough | Pleurobema plenum | - | 4 | E |
| Pigtoe, rough | Pleurobema plenum | U.S.A. (TN - specified portions of the French Broad and Holston Rivers; see 17.85(b)(1)) | 4 | EXPN |
| Pigtoe, shiny | Fusconaia cor | U.S.A. (TN - specified portions of the French Broad and Holston Rivers; see 17.85(b)(1)) | 4 | EXPN |
| Pigtoe, shiny | Fusconaia cor | U.S.A. (AL;The free-flowing reach of the Tennessee R. from the base of Wilson Dam downstream to the backwaters of Pickwick Reservoir [about 12 RM (19 km)] and the lower 5 RM [8 km] of all tributaries to this reach in Colbert and Lauderdale Cos., see 17.85(a)) | 4 | EXPN |
| Pigtoe, shiny | Fusconaia cor | Entire Range; Except where listed as Experimental Populations | 4 | E |
| Pigtoe, southern | Pleurobema georgianum | - | 4 | E |
| Pigtoe, Suwannee | Quincuncina kleiniana | - | 4 | SU |
| Pigtoe, tapered | Fusconaia burkei | - | 4 | C |
| Pigtoe, true | Pleurobema verum | - | 4 | SC |
| Pigtoe, warrior | Pleurobema rubellum | - | 4 | SC |
| pika, American | Ochotona princeps | - | 1 | RT |
| Pika, Barnes' | Ochotona princeps barnesi | - | 6 | SC |
| Pika, Cinnamon | Ochotona princeps cinnamomea | - | 6 | SC |
| Pika, Copenhagen Basin | Ochotona princeps clamosa | - | 1 | RT |
| Pika, Goat Peak | Ochotona princeps nigrescens | - | 2 | SC |
| Pika, Heliotrope | Ochotona princeps moorei | - | 6 | SC |
| Pika, La Sal | Ochotona princeps lasalensis | - | 6 | SC |
| Pika, Wasatch | Ochotona princeps wasatchensis | - | 6 | SC |
| Pike, blue | Stizostedion vitreum glaucum | - | 3 | D3A |
| Pikeminnow (=squawfish), Colorado | Ptychocheilus lucius | Salt and Verde R. drainages, AZ | 6 | EXPN |
| Pikeminnow (=squawfish), Colorado | Ptychocheilus lucius | Entire, except Salt and Verde R. drainages, AZ | 6 | E |
| Pillsnail, carinate | Euchemotrema hubrichti | - | 3 | SC |
| Pillsnail, palmetto | Euchemotrema cheatumi | - | 2 | SC |
| Pilo | Hedyotis mannii | - | 1 | E |
| Pilo kea lau li`i | Platydesma rostrata | - | 1 | E |
| Pilostyles, Thurber's | Pilostyles thurberi | - | 2 | RT |
| Pimpernel, mountain | Taenidia montana | - | 5 | RT |
| Pimpleback, orangefoot (pearlymussel) | Plethobasus cooperianus | U.S.A. (TN - specified portions of the French Broad and Holston Rivers; see 17.85(b)(1)) | 4 | EXPN |
| Pimpleback, orangefoot (pearlymussel) | Plethobasus cooperianus | - | 4 | E |
| Pimpleback, smooth | Quadrula houstonensis | - | 2 | UR |
| Pimpleback, Texas | Quadrula petrina | - | 2 | UR |
| Pincushion cactus, Guadalupe | Escobaria guadalupensis | - | 2 | SC |
| Pincushion cactus, Villard's | Escobaria villardii | - | 2 | SC |
| pincushionplant, Myers' | Navarretia myersii ssp. deminuta | - | 8 | SC |
| pincushionplant, prostrate | Navarretia prostrata | - | 1 | SC |
| pincushionplant, Tehama | Navarretia heterandra | - | 6 | SC |
| Pine, Bolander's beach | Pinus contorta bolanderi | - | 1 | SC |
| Pine, Monterey | Pinus radiata | - | 1 | SC |
| Pine, Ponderosa | Pinus ponderosa | - | 2 | SU |
| Pine, Torrey Island | Pinus torreyana insularis | - | 1 | SC |
| Pine, Torrey, Del Mar | Pinus torreyana torreyana | - | 1 | SC |
| Pine, undescribed | Pinus | - | NA | SU |
| Pine, whitebark | Pinus albicaulis | - | 6 | UR |
| Pine-foot, California | Pityopus californicus | - | 1 | RT |
| Pinesap, sweet | Monotropsis reynoldsiae | - | 4 | SC |
| Pink, swamp | Helonias bullata | - | 5 | T |
| Pinkroot, gentian | Spigelia gentianoides | - | 4 | E |
| Pinkroot, [unnamed] | Spigelia loganioides | - | 4 | SC |
| Pinkweed, Lake Erie | Polygonum pensylvanicum eglandulosum | - | 3 | RT |
| Pinon | Tillandsia lineatispica | - | 4 | SC |
| Pinon espinoso or cockspur | Erythrina eggersii | - | 4 | SC |
| Pintail, lesser white-cheeked | Anas bahamensis bahamensis | - | 4 | SC |
| Pintail, white-cheeked | Anas bahamensis | Puerto Rico | NA | SU |
| Pinweed, beach, Virginian | Lechea maritima virginica | - | 5 | RT |
| Pinweed, Chisos | Lechea mensalis | - | 2 | SC |
| Piperia, Yadon's | Piperia yadonii | - | 8 | E |
| Pipewort, Blackbract | Eriocaulon nigrobracteatum | - | 4 | SC |
| Pipewort, Parker's | Eriocaulon parkeri | - | 5 | RT |
| Pipewort, small-headed | Eriocaulon kornickianum | - | 4 | SC |
| Piping-guan, black-fronted | Pipile jacutinga | - | Foreign | E |
| pipistrelle, Western | pipistrellus hesperus | - | 6 | SC |
| Pipit, Sprague's | Anthus spragueii | - | 6 | UR |
| Piratebush | Buckleya distichophylla | - | 4 | SC |
| Pitaya, Correll's green | Echinocereus viridiflorus correllii | - | 2 | RT |
| Pitaya, Davis' green | Echinocereus viridiflorus var. davisii | - | 2 | E |
| Pitcher-plant, Alabama canebrake | Sarracenia rubra alabamensis | - | 4 | E |
| Pitcher-plant, green | Sarracenia oreophila | - | 4 | E |
| Pitcher-plant, mountain sweet | Sarracenia rubra ssp. jonesii | - | 4 | E |
| Pitcher-plant, parrot | Sarracenia psittacina | - | 4 | RT |
| Pitcher-plant, sweet, red-flowered | Sarracenia rubra rubra | - | 4 | RT |
| Pitcher-plant, [unnamed] | Sarracenia leucophylla | - | 4 | SC |
| Pitcher-plant, [unnamed] | Sarracenia rubra wherryi | - | 4 | SC |
| Pitcher-sage, Gander's | Lepechinia ganderi | - | 1 | SC |
| Pitcher-sage, heart-leaved | Lepechinia cardiophylla | - | 1 | SC |
| Pitcherplant, California | Darlingtonia californica | - | 1 | RT |
| Pitta, Gurney's | Pitta gurneyi | - | NA | E |
| Pitta, Koch's | Pitta kochi | - | Foreign | E |
| Pixie-moss, Well's | Pyxidanthera barbulata brevifolia | - | 4 | SC |
| Planarian, Bigger's groundwater | Sphalloplana subtilis | - | 5 | RT |
| Planarian, Culver's | Sphalloplana culveri | - | 5 | SC |
| Planarian, Holsinger's groundwater | Sphalloplana holsingeri | - | 5 | RT |
| Planarian, Refton Cave | Sphalloplana pricei | - | 5 | SC |
| Planarian, [unnamed] | Kenkia glandulosa | - | 3 | SC |
| Planarian, [unnamed] | Kenkia rhynchida | - | 1 | SC |
| Planarian, [unnamed] | Procotyla typhlops | - | 5 | SC |
| Planarian, [unnamed] | Sphalloplana virginiana | - | 5 | SC |
| Planigale, little | Planigale ingrami subtilissima | - | Foreign | E |
| Planigale, southern | Planigale tenuirostris | - | Foreign | E |
| Plantain, heart-leaved | Plantago cordata | - | 4 | RT |
| Plantain, pineland | Plantago sparsiflora | - | 4 | SC |
| Plantcutter, Peruvian | Phytotoma raimondii | - | Foreign | PE |
| Planthopper, Barber's Point oliarus | Oliarus myoporicola | - | 1 | SC |
| Planthopper, Bridewell's nesosydne | Nesosydne bridwelli | - | 1 | SC |
| Planthopper, Diamond Head nesosydne | Nesosydne leahi | - | 1 | SC |
| Planthopper, Glenwood nesosydne | Nesosydne cyrtandricola | - | 1 | SC |
| Planthopper, Iao Valley nesosydne | Nesosydne acuta | - | 1 | SC |
| Planthopper, Kauai parti-colored oliarus | Oliarus consimilis | - | 1 | SC |
| Planthopper, Keanae nesosydne | Nesosydne sulcata | - | 1 | SC |
| Planthopper, Kusche's nesosydne | Nesosydne kuschei | - | 1 | SC |
| Planthopper, Lanai oliarus | Oliarus lanaiensis | - | 1 | RT |
| Planthopper, Lihue oliarus | Oliarus lihue | - | 1 | SC |
| Planthopper, long-footed nesosydne | Nesosydne longipes | - | 1 | SC |
| Planthopper, Mt. Tantalus short-wing fern | Nesorestias filicicola | - | 1 | SC |
| Planthopper, Nahiku nesosydne | Nesosydne cyrtandrae | - | 1 | SC |
| Planthopper, oliarus wild cotton | Oliarus discrepans | - | 1 | SC |
| Planthopper, priolan oliarus | Oliarus priola | - | 1 | SC |
| Plover, mountain | Charadrius montanus | - | 6 | RT |
| Plover, New Zealand shore | Thinornis novaeseelandiae | - | Foreign | E |
| Plover, piping | Charadrius melodus | Great Lakes watershed in States of IL, IN, MI, MN, NY, OH, PA, and WI and Canada (Ont.) | 3 | E |
| Plover, piping | Charadrius melodus | Entire, except those areas where listed as endangered above | 5 | T |
| Plover, southeastern snowy | Charadrius alexandrinus tenuirostris | - | 4 | UR |
| Plover, western snowy | Charadrius alexandrinus nivosus | U.S.A. (CA, OR, WA), Mexico (within 50 miles of Pacific coast) | 8 | T |
| Plum, Alleghany | Prunus alleghaniensis | - | 5 | SC |
| Plum, beach, Grave's | Prunus maritima gravesii | - | 5 | RT |
| Plum, scrub | Prunus geniculata | - | 4 | E |
| Plume, Georgia | Elliottia racemosa | - | 4 | RT |
| Plymouth Red-Bellied Turtle | Pseudemys rubriventris bangsi | - | 5 | E |
| Pochard, Madagascar | Aythya innotata | - | Foreign | E |
| Pocket gopher, Amargosa southern | Thomomys umbrinus amargosae | - | 1 | RT |
| Pocket gopher, Animas southern | Thomomys umbrinus emotus | - | 2 | RT |
| Pocket gopher, Antelope Island | Thomomys umbrinus nesophilus | - | 6 | SC |
| Pocket gopher, Baker's Llano | Geomys texensis bakeri | - | 2 | SC |
| Pocket gopher, Bonneville southern | Thomomys umbrinus bonnevillei | - | 6 | SC |
| Pocket gopher, Brush Prairie | Thomomys mazama ssp. douglasii | - | 1 | C |
| Pocket gopher, Carrizo Springs Texas | Geomys personatus streckeri | - | 2 | SC |
| Pocket gopher, Cebolleta southern | Thomomys umbrinus paguatae | - | 2 | SC |
| Pocket gopher, Clear Lake | Thomomys umbrinus convexus | - | 6 | SC |
| Pocket gopher, Colonial | Geomys colonus | - | 4 | RT |
| Pocket gopher, Cumberland | Geomys cumberlandius | - | 4 | SC |
| Pocket gopher, desert | Geomys bursarius arenarius | - | 2 | SC |
| pocket gopher, Douglas County | Thomomys talpoides macrotis | entire | 6 | RT |
| Pocket gopher, Fish Spring | Thomomys umbrinus abstrusus | - | 1 | SC |
| Pocket gopher, Goff's southeastern | Geomys pinetis goffi | - | 4 | RT |
| Pocket gopher, Goldbeach western | Thomomys mazama helleri | - | 1 | SC |
| Pocket gopher, Graham Mountains | Thomomys umbrinus grahamensis | - | 2 | RT |
| Pocket gopher, Guadalupe southern | Thomomys umbrinus guadalupensis | - | 2 | SC |
| Pocket gopher, Harquahala southern | Thomomys umbrinus subsimilis | - | 2 | SC |
| Pocket gopher, Hualapai southern | Thomomys umbrinus hualpaiensis | - | 2 | SC |
| Pocket gopher, Limpia Creek | Thomomys umbrinus texensis | - | 2 | SC |
| Pocket gopher, Limpia southern | Thomomys umbrinus limpiae | - | 2 | SC |
| Pocket gopher, Louie's western | Thomomys mazama louiei | - | 1 | C |
| Pocket gopher, maritime Texas | Geomys personatus maritimus | - | 2 | SC |
| Pocket gopher, Mearns' southern | Thomomys umbrinus mearnsi | - | 2 | SC |
| Pocket gopher, Mer Rouge | Geomys bursarius breviceps | - | 4 | RT |
| Pocket gopher, Mount Ellen | Thomomys umbrinus dissimilis | - | 6 | SC |
| Pocket gopher, Olympia | Thomomys mazama pugetensis | - | 1 | C |
| Pocket gopher, Olympic | Thomomys mazama melanops | - | 1 | C |
| Pocket gopher, Pajarito southern | Thomomys umbrinus quercinus | - | 2 | SC |
| Pocket gopher, Pistol River | Thomomys umbrinus detumidus | - | 1 | SC |
| Pocket gopher, Prospect Valley | Thomomys umbrinus muralis | - | 2 | SC |
| Pocket gopher, Roy Prairie | Thomomys mazama glacialis | - | 1 | C |
| Pocket gopher, Salt Gulch | Thomomys umbrinus powelli | - | 6 | SC |
| Pocket gopher, San Antonio | Thomomys umbrinus curtatus | - | 1 | SC |
| Pocket gopher, Searchlight southern | Thomomys umbrinus suboles | - | 2 | SC |
| Pocket gopher, Shelton | Thomomys mazama ssp. couchi | - | 1 | C |
| Pocket gopher, Sherman's southeastern | Geomys pinetis fontanelus | - | 4 | RT |
| Pocket gopher, Skull Valley | Thomomys umbrinus robustus | - | 6 | SC |
| Pocket gopher, Stansbury Island | Thomomys umbrinus minimus | - | 6 | SC |
| Pocket gopher, Swasey Spring | Thomomys umbrinus sevieri | - | 6 | SC |
| Pocket gopher, Tacoma western | Thomomys mazama tacomensis | - | 1 | C |
| Pocket gopher, Tenino | Thomomys mazama tumuli | - | 1 | C |
| Pocket gopher, White Sands | Geomys arenarius brevirostris | - | 2 | RT |
| pocket gopher, Wyoming | Thomomys clusius | - | 6 | RT |
| Pocket gopher, Yelm | Thomomys mazama yelmensis | - | 1 | C |
| Pocketbook, fat | Potamilus capax | - | 4 | E |
| Pocketbook, finelined | Lampsilis altilis | - | 4 | T |
| Pocketbook, lined | Lampsilis binominata | - | 4 | SC |
| Pocketbook, Ouachita rock | Arkansia wheeleri | - | 2 | E |
| Pocketbook, shinyrayed | Lampsilis subangulata | - | 4 | E |
| Pocketbook, speckled | Lampsilis streckeri | - | 4 | E |
| Pogogyne, Santa Lucia | Pogogyne clareana | - | 1 | SC |
| Pogogyne, small-flowered, Douglas' | Pogogyne douglasii parviflora | - | 1 | RT |
| Pogonia, small whorled | Isotria medeoloides | - | 5 | T |
| Polygala, Lewton's | Polygala lewtonii | - | 4 | E |
| Polygala, tiny | Polygala smallii | - | 4 | E |
| Polygonum, Scotts Valley | Polygonum hickmanii | - | 8 | E |
| Polypody, dwarf | Grammitis nimbata | - | 4 | SC |
| Pomace fly, Lanai | Drosophila lanaiensis | - | 1 | SC |
| Pomace fly, [unnamed] | Drosophila aglaia | - | 1 | E |
| Pomace fly, [unnamed] | Drosophila differens | - | 1 | E |
| Pomace fly, [unnamed] | Drosophila hemipeza | - | 1 | E |
| Pomace fly, [unnamed] | Drosophila heteroneura | - | 1 | E |
| Pomace fly, [unnamed] | Drosophila montgomeryi | - | 1 | E |
| Pomace fly, [unnamed] | Drosophila mulli | - | 1 | T |
| Pomace fly, [unnamed] | Drosophila musaphila | - | 1 | E |
| Pomace fly, [unnamed] | Drosophila neoclavisetae | - | 1 | E |
| Pomace fly, [unnamed] | Drosophila obatai | - | 1 | E |
| Pomace fly, [unnamed] | Drosophila ochrobasis | - | 1 | E |
| Pomace fly, [unnamed] | Drosophila substenoptera | - | 1 | E |
| Pomace fly, [unnamed] | Drosophila tarphytrichia | - | 1 | E |
| Pondberry | Lindera melissifolia | - | 4 | E |
| Pondsnail, Fat-whorled (=Bonneville) | Stagnicola bonnevillensis | - | 6 | RT |
| Pondsnail, thickshell | Stagnicola utahensis | - | 6 | RT |
| Pondspice | Litsea aestivalis | - | 4 | SC |
| Pondweed, Hill's | Potamogeton hillii | - | 5 | RT |
| Pondweed, Little Aguja (=Creek) | Potamogeton clystocarpus | - | 2 | E |
| Pondweed, [unnamed] | Potamogeton confervoides | - | 3 | SC |
| Pondweed, [unnamed] | Potamogeton ogdenii | - | 5 | RT |
| Poolfish, Ash Meadows | Empetrichthys merriami | - | 1 | RT |
| Poolfish, Pahrump | Empetrichthys latos | - | 8 | E |
| popcornflower, Austin's | Plagiobothrys austiniae | - | 6 | SC |
| popcornflower, Bearded | Plagiobothrys hystriculus | - | 1 | RT |
| popcornflower, Greene's | Plagiobothrys greenei | - | 6 | SC |
| Popcornflower, Petaluma | Plagiobothrys mollis vestitus | - | 1 | SC |
| Popcornflower, rough | Plagiobothrys hirtus | - | 1 | E |
| Popcornflower, Salinas Valley | Plagiobothrys uncinatus | - | 1 | SC |
| Popcornflower, San Francisco | Plagiobothrys diffusus | - | 1 | SC |
| popcornflower, Sculptured | Plagiobothrys glyptocarpus var. glyptocarpus | - | 6 | SC |
| Popcornflower, [unnamed] | Plagiobothrys lamprocarpus | - | 1 | RT |
| Popolo | Cyanea solanacea | - | 1 | RT |
| Popolo | Solanum nelsonii | - | 1 | C |
| Popolo ku mai | Solanum incompletum | - | 1 | E |
| poppy, Coulter's matilija | romneya coulteri | - | 6 | SC |
| Poppy, diamond-petaled | Eschscholzia rhombipetala | - | 1 | SC |
| Poppy, Island | Eschscholzia ramosa | - | 1 | RT |
| Poppy, Kernville | Eschscholzia procera | - | 1 | SC |
| Poppy, pale | Papaver alboroseum | - | 7 | RT |
| Poppy, Sacramento prickly | Argemone pleiacantha ssp. pinnatisecta | - | 2 | E |
| Poppy, Walpole | Papaver walpolei | - | 7 | RT |
| Poppy-mallow, Texas | Callirhoe scabriuscula | - | 2 | E |
| Poppy-mallow, [unnamed] | Callirhoe bushii | - | 4 | RT |
| Porcupine, thin-spined | Chaetomys subspinosus | - | Foreign | E |
| Porpoise, Harbor | Phocoena phocoena | - | 5 | SU |
| Possum, Leadbeater's | Gymnobelideus leadbeateri | - | Foreign | E |
| Possum, mountain pygmy | Burramys parvus | - | Foreign | E |
| Possum, scaly-tailed | Wyulda squamicaudata | - | Foreign | E |
| Potato-bean, Price's | Apios priceana | - | 4 | T |
| Potentilla, Hickman's | Potentilla hickmanii | - | 8 | E |
| Po`e | Portulaca sclerocarpa | - | 1 | E |
| Po`ola | Claoxylon sandwicense sandwicense | - | 1 | RT |
| Po`ouli (honeycreeper) | Melamprosops phaeosoma | - | 1 | E |
| Prairie dog, Arizona black-tailed | Cynomys ludovicianus arizonensis | - | 2 | SC |
| Prairie dog, black-tailed | Cynomys ludovicianus | - | 6 | RT |
| Prairie dog, Gunnison's | Cynomys gunnisoni | central and south-central Colorado, north-central New Mexico | 6 | C |
| Prairie dog, Mexican | Cynomys mexicanus | - | Foreign | E |
| Prairie dog, Utah | Cynomys parvidens | - | 6 | T |
| Prairie-chicken, Attwater's greater | Tympanuchus cupido attwateri | - | 2 | E |
| Prairie-chicken, lesser | Tympanuchus pallidicinctus | - | 2 | C |
| Prairie-clover, Comanche-peak | Dalea reverchonii | - | 2 | SC |
| Prairie-clover, Florida | Dalea carthagenensis floridana | - | 4 | C |
| Prairie-clover, Hole-In-The-Rock | Dalea flavescens epica | - | 6 | SC |
| Prairie-clover, leafy | Dalea foliosa | - | 4 | E |
| Prairie-clover, Sabinal | Dalea sabinalis | - | 2 | SC |
| Prairie-clover, [unnamed] | Dalea scariosa | - | 2 | RT |
| Prickly-apple, aboriginal | Harrisia (=Cereus) aboriginum (=gracilis) | - | 4 | C |
| Prickly-apple, fragrant | Cereus eriophorus var. fragrans | - | 4 | E |
| Prickly-apple, Simpson's | Cereus gracilis simpsonii | - | 4 | SC |
| Prickly-ash, St. Thomas | Zanthoxylum thomasianum | - | 4 | E |
| Prickly-pear, cow-tongue | Opuntia lindheimeri linguiformis | - | 2 | RT |
| Prickly-pear, golden-spined | Opuntia aureispina | - | 2 | SC |
| Prickly-pear, marble-seeded, few-spined | Opuntia engelmannii flexospina | - | 2 | SC |
| Prickly-pear, sand | Opuntia arenaria | - | 2 | SC |
| Prickly-phlox, San Jacinto | Leptodactylon jaegeri | - | 1 | RT |
| Prickly-poppy, robust | Argemone munita robusta | - | 1 | RT |
| primrose Baird's evening | Camissonia bairdii | - | 6 | SC |
| Primrose, bird's-eye | Primula mistassinica | - | 3 | RT |
| Primrose, Maguire | Primula maguirei | - | 6 | T |
| Primrose, North Rim | Primula hunnewellii | - | 2 | SC |
| Primrose, Wallowa | Primula cusickiana | - | 1 | RT |
| Primrose, [unnamed] | Primula alcalina | - | 1 | SC |
| Primrose, [unnamed] | Primula capillaris | - | 1 | SC |
| Primrose, [unnamed] | Primula domensis | - | 6 | SC |
| Primrose, [unnamed] | Primula nevadensis | - | 1 | SC |
| Primrose, [unnamed] | Primula specuicola | - | 2 | RT |
| Primrose, [unnamed] | Primula tschuktschorum | - | 7 | SC |
| Primrose, [unnamed] | Primula wilcoxiana | - | 1 | RT |
| Pronghorn, peninsular | Antilocapra americana peninsularis | - | Foreign | E |
| Pronghorn, Sonoran | Antilocapra americana sonoriensis | - | 2 | E |
| Proterhinid beetles, Hawaiian | Proterhinus spp. (ca 72) | - | 1 | SC |
| Pseudoscorpion | Kleptochthonius magnus | - | 4 | SU |
| Pseudoscorpion | Kleptochthonius tantalus | - | 4 | SU |
| pseudoscorpion, (Aphrastochthonius) | aphrastochthonius | - | 6 | SC |
| pseudoscorpion, (Tartarocreagris) | tartarocreagris | - | 6 | SC |
| Pseudoscorpion, Aalbu's cave | Archeolarca aalbui | - | 1 | SC |
| Pseudoscorpion, Carlow's Cave | Aphrastochthonius similis | - | 1 | SC |
| Pseudoscorpion, Dry Fork Valley cave | Apochthonius paucispinosus | - | 5 | SC |
| Pseudoscorpion, Empire Cave | Microcreagris imperialis | - | 1 | SC |
| Pseudoscorpion, Grand Canyon cave | Archeolarca cavicola | - | 2 | SC |
| Pseudoscorpion, Greenbrier Valley cave | Kleptochthonius henroti | - | 5 | SC |
| Pseudoscorpion, Grubbs' cave | Aphrastochthonius grubbsi | - | 1 | SC |
| Pseudoscorpion, Guadalupe cave | Archeolarca guadalupensis | - | 2 | SC |
| Pseudoscorpion, Lacey's cave | Larca laceyi | - | 1 | SC |
| Pseudoscorpion, Malheur | Apochthonius malheuri | - | 1 | SC |
| Pseudoscorpion, Music Hall Cave | Pseudogarypus orpheus | - | 1 | SC |
| Pseudoscorpion, Organ Cave | Kleptochthonius hetricki | - | 5 | SC |
| Pseudoscorpion, Orpheus cave | Kleptochthonius orpheus | - | 5 | SC |
| Pseudoscorpion, Proserpina cave | Kleptochthonius proserpinae | - | 5 | SC |
| Pseudoscorpion, royal syarinid | Chitrella regina | - | 5 | SC |
| Pseudoscorpion, Tooth Cave | Tartarocreagris texana | - | 2 | E |
| Psyllid, Oahu holio gall | Paurotriozana adaptata | - | 1 | SC |
| Ptarmigan, Evermann's rock | Lagopus mutus evermanni | - | 7 | SC |
| Ptarmigan, Yunaska rock | Lagopus mutus yunaskensis | - | 7 | SC |
| Pua `ala | Brighamia rockii | - | 1 | E |
| Pua-hekili | Lysimachia hillebrandii | - | 1 | RT |
| Pua-kauhi | Canavalia rockii | - | 1 | RT |
| Pualoalo | Hibiscus kokio | - | 1 | SC |
| Pudu | Pudu pudu | - | Foreign | E |
| puffin, Atlantic | Fratercula arctica | - | 5 | SC |
| Puffin, Tufted | Fratercula cirrhata | - | 1 | SC |
| Puffleg, black-breasted | Eriocnemis nigrivestis | - | Foreign | PE |
| Puffleg, black-breasted | Eriocnemis nigrivestris | - | NA | SU |
| Puma (=cougar), eastern | Puma (=Felis) concolor couguar | - | 5 | E |
| Puma (=mountain lion) | Puma (=Felis) concolor (all subsp. except coryi) | U.S.A. (FL) | 5 | SAT |
| Puma, Costa Rican | Puma (=Felis) concolor costaricensis | - | Foreign | E |
| Puma, Wisconsin | Felis concolor schorgeri | - | 3 | SC |
| Puma, Yuma | Felis concolor browni | - | 2 | SC |
| Pupfish, Ash Meadows Amargosa | Cyprinodon nevadensis mionectes | - | 8 | E |
| Pupfish, Comanche Springs | Cyprinodon elegans | - | 2 | E |
| Pupfish, Conchos | Cyprinodon eximius | - | 2 | SC |
| Pupfish, desert | Cyprinodon macularius | - | 2 | E |
| Pupfish, Devils Hole | Cyprinodon diabolis | - | 8 | E |
| Pupfish, Leon Springs | Cyprinodon bovinus | - | 2 | E |
| Pupfish, Monkey Springs | Cyprinodon spp | - | NA | SU |
| Pupfish, Owens | Cyprinodon radiosus | - | 8 | E |
| Pupfish, Palomas | Cyprinodon sp. | - | 2 | SC |
| Pupfish, Pecos | Cyprinodon pecosensis | - | 2 | RT |
| Pupfish, Shoshone | Cyprinodon nevadensis shoshone | - | 1 | SC |
| Pupfish, Tecopa | Cyprinodon nevadensis calidae | - | 8 | D3A |
| Pupfish, Warm Springs | Cyprinodon nevadensis pectoralis | - | 8 | E |
| Pupfish, White Sands | Cyprinodon tularosa | - | 2 | SC |
| Pus pilo | Capparis sandwichiana | - | 1 | SC |
| Pussypaws, Mariposa | Calyptridium pulchellum | - | 8 | T |
| Pussytoes, meadow | Antennaria arcuata | - | 1 | SC |
| Pu`uka`a | Cyperus trachysanthos | - | 1 | E |
| Pygmy-owl, cactus ferruginous | Glaucidium brasilianum cactorum | U.S.A. (AZ) | 2 | DO |
| Pygmypipes | Monotropsis odorata | - | 4 | SC |
| Pyralid moth, Daecke's | Crambus daeckeellus | - | 5 | SC |
| Pyrg, bifid duct | Pyrgulopsis peculiaris | - | 6 | SU |
| Pyrg, Big Warm Spring | Pyrgulopsis papillata | - | 8 | SU |
| Pyrg, Blue Point | Pyrgulopsis coloradensis | - | 8 | SU |
| Pyrg, Briley Creek | Pyrgulopsis sp. | Briley Creek | 4 | SC |
| Pyrg, Butterfield | Pyrgulopsis lata | - | 8 | SU |
| Pyrg, Camp Valley | Pyrgulopsis montana | - | 8 | SU |
| Pyrg, Corn Creek | Pyrgulopsis fausta | - | 8 | SU |
| Pyrg, Duckwater | Pyrgulopsis aloba | - | 8 | SU |
| Pyrg, Duckwater Warm Springs | Pyrgulopsis villacampae | - | 8 | SU |
| Pyrg, emigrant | Pyrgulopsis gracilis | - | 8 | SU |
| Pyrg, flag | Pyrgulopsis breviloba | - | 8 | SU |
| Pyrg, flat-topped Steptoe | Pyrgulopsis planulata | - | 8 | SU |
| Pyrg, Flint River | Pyrgulopsis sp. | Flint R. | 4 | SC |
| Pyrg, Hamlin Valley | Pyrgulopsis hamlinensis | - | 6 | UR |
| Pyrg, hardy | Pyrgulopsis marcida | - | 8 | SU |
| Pyrg, Hubbs | Pyrgulopsis hubbsi | - | 8 | SU |
| Pyrg, Lake Valley pryg | Pyrgulopsis sublata | - | 8 | SU |
| Pyrg, Landyes | Pyrgulopsis landyei | - | 8 | SU |
| Pyrg, Lockes | Pyrgulopsis lockensis | - | 8 | SU |
| Pyrg, longitudinal | Pyrgulopsis anguina | - | 8 | UR |
| Pyrg, Moapa Valley | Pyrgulopsis carinifera | - | 8 | SU |
| Pyrg, Neritiform Steptoe Ranch | Pyrgulopsis neritella | - | 8 | SU |
| Pyrg, Northern Steptoe | Pyrgulopsis serrata | - | 8 | SU |
| Pyrg, Ozark | Pyrgulopsis ozarkensis | - | 4 | SC |
| Pyrg, Southeast Nevada | Pyrgulopsis turbatrix | - | 8 | SU |
| Pyrg, Southern Duckwater | Pyrgulopsis anatina | - | 8 | SU |
| Pyrg, Southern Steptoe | Pyrgulopsis sulcata | - | 8 | SU |
| Pyrg, Spring Creek | Pyrgulopsis sp. | Spring Creek | 4 | SC |
| Pyrg, Spring Mountains | Pyrgulopsis deaconi | - | 8 | SU |
| Pyrg, Sterile Basin | Pyrgulopsis sterilis | - | 8 | SU |
| Pyrg, sub-globose Snake | Pyrgulopsis saxatilis | - | 6 | UR |
| Pyrg, sub-globose Steptoe Ranch | Pyrgulopsis orbiculata | - | 8 | SU |
| Pyrg, White River Valley | Pyrgulopsis sathos | - | 8 | SU |
| Pyrrocoma, Bear Valley | Pyrrocoma uniflora gossypina | - | 1 | SC |
| Python, Indian | Python molurus molurus | - | Foreign | E |
| Quail, Merriam's Montezuma | Cyrtonyx montezumae merriami | - | Foreign | E |
| Quail, mountain | Oreortyx pictus | - | 1 | RT |
| Queen-of-the-forest | Filipendula occidentalis | - | 1 | SC |
| Quetzel, resplendent | Pharomachrus mocinno | - | Foreign | E |
| Quillwort, black spored | Isoetes melanospora | - | 4 | E |
| Quillwort, Eaton's | Isoetes eatonii | - | 5 | RT |
| Quillwort, Louisiana | Isoetes louisianensis | - | 4 | E |
| Quillwort, mat-forming | Isoetes tegetiformans | - | 4 | E |
| Quillwort, Orcutt's | Isoetes orcuttii | - | 1 | RT |
| Quillwort, pitted | Isoetes foveolata | - | 5 | RT |
| Quillwort, pygmy | Isoetes bolanderi pygmaea | - | 1 | RT |
| Quillwort, rock | Isoetes lithophylla | - | 2 | SC |
| quillwort, Virginia | Isoetes virginica | - | 5 | SC |
| Quillwort, [unnamed] | Isoetes flaccida | - | 4 | RT |
| Quina | Antirhea portoricensis | - | 4 | RT |
| Quokka | Setonix brachyurus | - | Foreign | E |
| Rabbit, Appalachian cottontail | Sylvilagus obscurus | - | 4 | UR |
| rabbit, brush | Sylvilagus bachmani | - | 1 | SC |
| Rabbit, Davis Mountains cottontail | Sylvilagus floridanus robustus | - | 2 | SC |
| Rabbit, Lower Keys marsh | Sylvilagus palustris hefneri | - | 4 | E |
| Rabbit, Micco cottontail | Sylvilagus floridanus ammophilus | - | 4 | RT |
| Rabbit, New England cottontail | Sylvilagus transitionalis | - | 5 | C |
| Rabbit, pygmy | Brachylagus idahoensis | - | 1 | UR |
| Rabbit, pygmy | Brachylagus idahoensis | Columbia Basin DPS | 1 | E |
| Rabbit, riparian brush | Sylvilagus bachmani riparius | - | 8 | E |
| Rabbit, Ryukyu | Pentalagus furnessi | - | Foreign | E |
| Rabbit, Smiths Island cottontail | Sylvilagus floridanus hitchensi | - | 5 | SC |
| Rabbit, volcano | Romerolagus diazi | - | Foreign | E |
| Rabbitsfoot | Quadrula cylindrica cylindrica | - | 4 | C |
| Rabbitsfoot, rough | Quadrula cylindrica strigillata | - | 5 | E |
| rabdotus, Santa Rita | Naesiotus christenseni | - | 2 | SU |
| Raccoon, Key Vaca | Procyon lotor auspicatus | - | 4 | SC |
| Raccoon, Key West | Procyon lotor incautus | - | 4 | SC |
| Racer, St. Croix | Alsophis sancticrucis | - | 4 | RT |
| Ragwort, Ertter's | Senecio ertterae | - | 1 | RT |
| ragwort, Piedmont | Packera millefolia | - | 4 | SC |
| Ragwort, pussytoes | Senecio antennariifolius | - | 5 | RT |
| Rail, Aukland Island | Rallus pectoralis muelleri | - | Foreign | E |
| Rail, barred-wing | Rallus poecilopterus | - | Foreign | UR |
| rail, Black | Laterallus jamaicensis | - | 3 | SC |
| Rail, Bogota | Rallus semiplumbeus | - | Foreign | UR |
| rail, California black | laterallus jamaicensis ssp. coturniculus | - | 8 | SC |
| Rail, California clapper | Rallus longirostris obsoletus | - | 8 | E |
| Rail, clapper | Rallus longirostris | - | 4 | SC |
| Rail, Guam | Rallus owstoni | Rota | 1 | EXPN |
| Rail, Guam | Rallus owstoni | Entire, except Rota | 1 | E |
| Rail, Junin | Laterallus tuerosi | - | Foreign | PE |
| Rail, king | Rallus elegans | - | 4 | SC |
| Rail, light-footed clapper | Rallus longirostris levipes | U.S.A. only | 8 | E |
| Rail, Lord Howe wood | Gallirallus (=Tricholimnas) sylvestris | - | Foreign | E |
| Rail, mangrove clapper | Rallus longirostris insularum | - | 4 | SC |
| Rail, Yuma clapper | Rallus longirostris yumanensis | U.S.A. only | 2 | E |
| Railardella, scabrid | Raillardella scabrida | - | 1 | RT |
| Raillardella, Muir's | Raillardella muirii | - | 1 | RT |
| Raillardella, showy | Raillardella pringlei | - | 1 | SC |
| Railliardia, Sherff | Dubautia sherffiana | - | 1 | SC |
| Rams-horn Great Basin | Helisoma newberryi | - | 6 | SC |
| Rams-horn Lamb | Planorbella oregonensis | - | 6 | SC |
| Rams-horn, acorn | Planorbella multivolvis | - | 3 | SC |
| Rams-horn, Greenfield | Taphius eucosmius eucosmius | - | 4 | RT |
| Rams-horn, Knobby | Vorticifex sp | - | 8 | SU |
| Rams-horn, magnificent | Planorbella magnifica | - | 4 | SC |
| Raspberry, Cuyamaca | Rubus glaucifolius ganderi | - | 1 | SC |
| Rat, false water | Xeromys myoides | - | Foreign | E |
| Rat, stick-nest | Leporillus conditor | - | Foreign | E |
| Rat-kangaroo, brush-tailed | Bettongia penicillata | - | Foreign | E |
| Rat-kangaroo, desert (=plain) | Caloprymnus campestris | - | Foreign | E |
| Rat-kangaroo, Gaimard's | Bettongia gaimardi | - | Foreign | E |
| Rat-kangaroo, Lesuer's | Bettongia lesueur | - | Foreign | E |
| Rat-kangaroo, Queensland | Bettongia tropica | - | Foreign | E |
| Rattlesnake root, barbed | Prenanthes barbata | - | 4 | SC |
| Rattlesnake root, Boott's | Prenanthes boottii | - | 5 | SC |
| Rattlesnake root, mountain | Prenanthes roanensis | - | 4 | RT |
| Rattlesnake, Arizona ridge-nosed | Crotalus willardi willardi | - | 2 | RT |
| Rattlesnake, Aruba Island | Crotalus unicolor | - | Foreign | T |
| rattlesnake, Mojave green | crotalus scutulatus ssp. scutulatus | - | 2 | SC |
| Rattlesnake, New Mexican ridge-nosed | Crotalus willardi obscurus | - | 2 | T |
| Rattlesnake, northern red diamond | Crotalus ruber ruber | - | 1 | SC |
| rattlesnake, Speckled | crotalinae mitchellii | - | 6 | SC |
| Rattlesnake, timber | Crotalus horridus | - | NA | RT |
| Rattleweed, Cima | Astragalus cimae cimae | - | 1 | RT |
| Rattleweed, hairy | Baptisia arachnifera | - | 4 | E |
| redhorse, Gray | moxostoma congestum | - | 2 | SC |
| Redhorse, greater | Moxostoma valenciennesi | - | 6 | SC |
| Redhorse, robust | Moxostoma robustum | - | 4 | SC |
| Redhorse, Sicklefin | Moxostoma sp. | - | 4 | C |
| Reduviid, Smith's siacellan | Saicella smithi | - | 1 | SC |
| Reed-mustard, Barneby | Schoenocrambe barnebyi | - | 6 | E |
| Reed-mustard, clay | Schoenocrambe argillacea | - | 6 | T |
| Reed-mustard, shrubby | Schoenocrambe suffrutescens | - | 6 | E |
| Reedgrass, Cain's | Calamagrostis cainii | - | 4 | SC |
| Reedgrass, dense | Calamagrostis densa | - | 1 | RT |
| Reedgrass, Hillegrand's | Calamagrostis hillebrandii | - | 1 | C |
| Reedgrass, leafy | Calamagrostis foliosa | - | 1 | RT |
| Reedgrass, Maui | Calamagrostis expansa | - | 1 | C |
| Reedgrass, northern (=New England) | Calamagrostis inexpansa novae-angliae | - | 5 | RT |
| Reedgrass, Ofer Hollow | Calamagrostis porteri insperata | - | 3 | SC |
| Reedgrass, Porter's | Calamagrostis porteri | - | 4 | RT |
| Reedgrass, Thurber's | Calamagrostis crassiglumis | - | 1 | SC |
| Reedgrass, wood | Calamagrostis perplexa | - | 5 | SC |
| Reedgrass, [unnamed] | Calamagrostis nubila | - | 5 | RT |
| Reedgrass, [unnamed] | Calamagrostis tweedyi | - | 1 | RT |
| Rein orchid, Alaska | Platanthera unalascensis maritima | - | 1 | RT |
| Rein-orchid, southern | Platanthera flava | - | 4 | RT |
| Remya, Maui | Remya mauiensis | - | 1 | E |
| Rhea, lesser (incl. Darwin's) | Rhea (=Pterocnemia) pennata | - | Foreign | E |
| Rhinoceros, black | Diceros bicornis | - | Foreign | E |
| Rhinoceros, great Indian | Rhinoceros unicornis | - | Foreign | E |
| Rhinoceros, Javan | Rhinoceros sondaicus | - | Foreign | E |
| Rhinoceros, northern white | Ceratotherium simum cottoni | - | Foreign | E |
| Rhinoceros, Sumatran | Dicerorhinus sumatrensis | - | Foreign | E |
| Rhododendron, Baker's | Rhododendron bakeri | - | 4 | RT |
| Rhododendron, Chapman | Rhododendron chapmanii | - | 4 | E |
| Rhododendron, [unnamed] | Rhododendron austrinum | - | 4 | RT |
| Rice rat | Oryzomys palustris natator | Lower FL Keys (west of Seven Mile Bridge) | 4 | E |
| Rice rat, Coues' | Oryzomys couesi aquaticus | - | 2 | SC |
| Rice rat, Pine Island | Oryzomys palustris planirostris | - | 4 | RT |
| Rice rat, Sanibel Island | Oryzomys palustris sanibeli | - | 4 | RT |
| Rice rat, silver | Oryzomys argentatus | - | NA | SU |
| Ridge-cress, Barneby | Lepidium barnebyanum | - | 6 | E |
| Riffle beetle, Brown's microcylloepus | Microcylloepus browni | - | 6 | SC |
| Riffle beetle, Brown's optioservus | Optioservus browni | - | 4 | SC |
| Riffle beetle, brownish dubiraphian | Dubiraphia brunnescens | - | 1 | SC |
| Riffle beetle, Devil's Hole warm spring | Stenelmis calida calida | - | 1 | UR |
| Riffle beetle, Douglas stenelmis | Stenelmis douglasensis | - | 3 | SC |
| Riffle beetle, dubiraphian | Dubiraphia sp. | - | 5 | RT |
| Riffle beetle, Gammon's stenelmis | Stenelmis gammoni | - | 4 | SC |
| Riffle beetle, Giuliani's dubiraphian | Dubiraphia giulianii | - | 1 | SC |
| Riffle beetle, little | Dubiraphia parva | - | 4 | SC |
| Riffle beetle, Marron's San Carlos | Huleechius marroni carolus | - | 2 | SC |
| Riffle beetle, Moapa warm springs | Stenelmis calida moapa | - | 1 | UR |
| Riffle beetle, Parker's | Cylloepus parkeri | - | 2 | SC |
| Riffle beetle, Pinnacles optioservus | Optioservus canus | - | 1 | SC |
| Riffle beetle, robust dubiraphian | Dubiraphia robusta | - | 3 | SC |
| Riffle beetle, Scott optioservus | Optioservus phaeus | - | 6 | SC |
| Riffle beetle, Stephan's | Heterelmis stephani | - | 2 | C |
| Riffle beetle, Wawona | Atractelmis wawona | - | 1 | SC |
| Riffle beetle, [unnamed] | Microcylleopus fomicoideus | - | 1 | SC |
| Riffle beetle, [unnamed] | Microcylleopus similis | - | 1 | SC |
| Riffleshell, angled | Epioblasma biemarginata | - | 4 | RT |
| Riffleshell, northern | Epioblasma torulosa rangiana | - | 5 | E |
| Riffleshell, tan | Epioblasma florentina walkeri (=E. walkeri) | - | 4 | E |
| Riffleshell, Tennessee | Epioblasma propinqua | - | 4 | RT |
| Ring pink (mussel) | Obovaria retusa | - | 4 | E |
| Ring pink (mussel) | Obovaria retusa | U.S.A. (TN - specified portions of the French Broad and Holston Rivers; see 17.85(b)(1)) | 4 | EXPN |
| ringstem, Sticky | anulocaulis leiosolenus | - | 6 | SC |
| Ringtail | bassariscus astutus | - | 6 | SC |
| Riversnail, Anthony's | Athearnia anthonyi | U.S.A. (TN - specified portions of the French Broad and Holston Rivers; see 17.85(b)(1)) | 4 | EXPN |
| Riversnail, Anthony's | Athearnia anthonyi | U.S.A. (AL;The free-flowing reach of the Tennessee R. from the base of Wilson Dam downstream to the backwaters of Pickwick Reservoir [about 12 RM (19 km)] and the lower 5 RM [8 km] of all tributaries to this reach in Colbert and Lauderdale Cos., see 17.85(a)) | 4 | EXPN |
| Riversnail, Anthony's | Athearnia anthonyi | Entire Range; Except where listed as Experimental Populations | 4 | E |
| Riversnail, spiny | Io fluvialis | - | 5 | UR |
| Roach, Gualala | Lavinia symmetricus parvipinnis | - | 1 | SC |
| Roach, pit | Lavinia symmetricus mitrulus | - | 1 | SC |
| Roach, Red Hills | Lavinia symmetricus ssp. | - | 1 | SC |
| Roach, Tuna Cave | Aspiduchus cavernicola | - | 4 | SC |
| Robber fly, Oso Flaco | Ablautus schlingeri | - | 1 | SC |
| Robberfly, Antioch cophuran | Cophura hurdi | - | 1 | SC |
| Robberfly, Antioch efferian | Efferia antiochi | - | 1 | SC |
| Robberfly, Hurd's metapogon | Metapogon hurdi | - | 1 | SC |
| Robin, Chatham Island | Petroica traversi | - | Foreign | E |
| Robin, dappled mountain | Arcanator orostruthus | - | Foreign | T |
| Robin, scarlet-breasted (flycatcher) | Petroica multicolor multicolor | - | Foreign | E |
| Robin, Southern Ryukyu | Erithacus komadori subrufa | - | Foreign | UR |
| Rock lady | Holmgrenanthe petrophila | - | 1 | SC |
| Rock-aster, Alexander's | Eurybia avitus | - | 4 | SC |
| Rock-cress, Bodie Hills | Arabis bodiensis | - | 1 | SC |
| Rock-cress, Boundary Peak | Arabis pinzlae | - | 1 | SC |
| Rock-cress, Braun's | Arabis perstellata | - | 4 | E |
| Rock-cress, Chico Creek | Arabis breweri austinae | - | 1 | RT |
| Rock-cress, coast | Arabis blepharophylla | - | 1 | RT |
| Rock-cress, Constance's | Arabis constancei | - | 1 | RT |
| Rock-cress, Daggett, | Arabis demissa languida | - | 6 | RT |
| Rock-cress, Daggett, | Arabis demissa russeola | - | 6 | RT |
| Rock-cress, fruit | Arabis fructicosa | - | 6 | RT |
| Rock-cress, Galena Creek | Arabis rigidissima demota | - | 1 | SC |
| Rock-cress, Hoffmann's | Arabis hoffmannii | - | 8 | E |
| Rock-cress, Johnston's | Arabis johnstonii | - | 1 | RT |
| Rock-cress, Koehler's | Arabis koehleri koehleri | - | 1 | SC |
| Rock-cress, McDonald's | Arabis macdonaldiana | - | 8 | E |
| Rock-cress, modest | Arabis modesta | - | 1 | RT |
| Rock-cress, Oregon | Arabis oregana | - | 1 | RT |
| Rock-cress, Parish's | Arabis parishii | - | 1 | SC |
| Rock-cress, Park | Arabis vivariensis | - | 6 | SC |
| Rock-cress, Preston Peak | Arabis serpentinicola | - | 1 | SC |
| Rock-cress, pygmy | Arabis pygmaea | - | 1 | RT |
| Rock-cress, San Bernardino | Arabis breweri pecuniaria | - | 1 | SC |
| Rock-cress, Sapphire Mt. | Arabis fecunda | - | 6 | SC |
| Rock-cress, shale barren | Arabis serotina | - | 5 | E |
| Rock-cress, Shockley's | Arabis shockleyi | - | 1 | RT |
| Rock-cress, small | Arabis pusilla | - | 6 | UR |
| Rock-cress, sp. nov. ined. (Del Norte) | Arabis sp. | Del Norte | 1 | SC |
| Rock-cress, sp. nov. ined. (Gray Knolls) | Arabis sp. | Gray Knolls | 6 | RT |
| Rock-cress, Tiehm's | Arabis tiehmii | - | 1 | SC |
| Rock-cress, Waldo | Arabis aculeolata | - | 1 | RT |
| Rock-cress, [unnamed] | Arabis crandallii | - | 6 | RT |
| Rock-cress, [unnamed] | Arabis dispar | - | 1 | RT |
| Rock-cress, [unnamed] | Arabis falcatoria | - | 6 | SC |
| Rock-cress, [unnamed] | Arabis falcifructa | - | 1 | SC |
| Rock-cress, [unnamed] | Arabis gracilipes | - | 2 | RT |
| Rock-cress, [unnamed] | Arabis gunnisoniana | - | 6 | RT |
| Rock-cress, [unnamed] | Arabis koehleri stipitata | - | 1 | RT |
| Rock-cress, [unnamed] | Arabis ophira | - | 1 | SC |
| Rock-cress, [unnamed] | Arabis petiolaris | - | 2 | RT |
| Rock-cress, [unnamed] | Arabis williamsii | - | 6 | RT |
| Rock-daisy, Ajo | Perityle ajoensis | - | 2 | RT |
| Rock-daisy, Chiricahua | Perityle cochisensis | - | 2 | RT |
| Rock-daisy, Fish Creek | Perityle saxicola | - | 2 | SC |
| Rock-daisy, Glass Mountain | Perityle vitreomontana | - | 2 | SC |
| Rock-daisy, gray | Perityle cinerea | - | 2 | RT |
| Rock-daisy, Hueco | Perityle huecoensis | - | 2 | SC |
| Rock-daisy, nodding | Perityle cernua | - | 2 | SC |
| Rock-daisy, river | Perityle warnockii | - | 2 | SC |
| Rock-daisy, stairstep two-bristle | Perityle bisetosa scalaris | - | 2 | SC |
| Rock-daisy, two-bristle | Perityle bisetosa bisetosa | - | 2 | SC |
| Rock-daisy, [unnamed] | Perityle gilensis salensis | - | 2 | RT |
| Rock-daisy, [unnamed] | Perityle lindheimeri halimifolia | - | 2 | RT |
| Rock-daisy, [unnamed] | Perityle lindheimeri lindheimeri | - | 2 | RT |
| Rock-fringe, Siskiyou | Epilobium siskiyouense | - | 1 | RT |
| Rock-mint, felt leaf | Monardella hypoleuca lanata | - | 1 | RT |
| Rock-rose, Diablo | Helianthella castanea | - | 1 | SC |
| Rockcress, Georgia | Arabis georgiana | - | 4 | C |
| Rockcress, Santa Cruz Island | Sibara filifolia | - | 8 | E |
| Rockfowl, grey-necked | Picathartes oreas | - | Foreign | E |
| Rockfowl, white-necked | Picathartes gymnocephalus | - | Foreign | E |
| Rockmat, chelan | Petrophytum cinerascens | - | 1 | SC |
| Rocksnail, agate | Leptoxis clipeata | - | 4 | RT |
| Rocksnail, armored | Lithasia armigera | - | 4 | SC |
| Rocksnail, bigmouth | Leptoxis occulata | - | 4 | RT |
| Rocksnail, Coosa | Leptoxis showalteri | - | 4 | RT |
| Rocksnail, helmet | Lithasia duttoniana | - | 4 | SC |
| Rocksnail, interrupted | Leptoxis formani deprecated | - | 4 | RT |
| Rocksnail, interrupted (=Georgia) | Leptoxis foremani | - | 4 | PE |
| Rocksnail, knobby | Lithasia curta | - | 4 | SC |
| Rocksnail, lyrate | Leptoxis lirata | - | 4 | RT |
| Rocksnail, maiden | Leptoxis formosa | - | 4 | RT |
| Rocksnail, muddy | Lithasia salebrosa | - | 4 | SC |
| Rocksnail, oblong | Leptoxis compacta | - | 4 | SC |
| Rocksnail, onyx | Leptoxis praerosa | - | 4 | SC |
| Rocksnail, ornate | Lithasia geniculata | - | 4 | SC |
| Rocksnail, painted | Leptoxis taeniata | - | 4 | T |
| Rocksnail, plicate | Leptoxis plicata | - | 4 | E |
| Rocksnail, rotund | Leptoxis ligata | - | 4 | RT |
| Rocksnail, round | Leptoxis ampla | - | 4 | T |
| Rocksnail, rugose | Lithasia jayana | - | 4 | SC |
| Rocksnail, smooth | Leptoxis virgata | - | 4 | SC |
| Rocksnail, spotted | Leptoxis picta | - | 4 | SC |
| Rocksnail, striped | Leptoxis vittata | - | 4 | RT |
| Rocksnail, varicose | Lithasia verrucosa | - | 4 | SC |
| Rocksnail, warty | Lithasia lima | - | 4 | SC |
| Roller, long-tailed ground | Uratelornis chimaera | - | Foreign | E |
| Rose, Grand Canyon | Rosa stellata abyssa | - | 2 | SC |
| Rose, small-leaved | Rosa minutifolia | - | 1 | SC |
| Rose-mallow, Neches River | Hibiscus dasycalyx | - | 2 | C |
| Rosemary, Apalachicola | Conradina glabra | - | 4 | E |
| Rosemary, Cumberland | Conradina verticillata | - | 4 | T |
| Rosemary, Etonia | Conradina etonia | - | 4 | E |
| Rosemary, short-leaved | Conradina brevifolia | - | 4 | E |
| Rosemary, [unnamed] | Conradina grandiflora | - | 4 | SC |
| Rosemary-mint | Poliomintha glabrescens | - | 2 | RT |
| Roseroot, Leedy's | Sedum integrifolium ssp. leedyi | - | 3 | T |
| Rosewood, limestone | Vauquelinia californica pauciflora | - | 2 | SC |
| Rosinweed, Fremont's | Calycadenia fremontii | - | 1 | SC |
| Rosinweed, Hoover's | Calycadenia hooveri | - | 1 | SC |
| Rosinweed, [unnamed] | Silphium brachiatum | - | 4 | SC |
| Rosinweed, [unnamed] | Silphium integrifolium gattingeri | - | 4 | RT |
| Rove beetle, black lordithon | Lordithon niger | - | 5 | SC |
| rush, Ahart's dwarf | Juncus leiospermus var. ahartii | - | 1 | SC |
| Rush, bog, Barnstable | Juncus pervetus | - | 5 | RT |
| Rush, New Jersey | Juncus caesariensis | - | 5 | SC |
| Rush, Red Bluff | Juncus leiospermus leiospermus | - | 1 | RT |
| Rush, [unnamed] | Juncus gymnocarpus | - | 4 | RT |
| Rush, [unnamed] | Juncus oronensis | - | 5 | RT |
| Rush-pea, slender | Hoffmannseggia tenella | - | 2 | E |
| Rush-rose, Amador | Helianthemum suffrutescens | - | 1 | RT |
| Rush-rose, bushy | Helianthemum dumosum | - | 5 | SC |
| Rush-rose, island | Helianthemum greenei | - | 8 | T |
| Rushpea, broad-pod | Caesalpinia brachycarpa | - | 2 | SC |
| Sacahuista, sand | Nolina arenicola | - | 2 | SC |
| sage grouse, Gunnison | Centrocercus minimus | entire | 6 | UR |
| Sage, Aravaipa | Salvia amissa | - | 2 | SC |
| Sage, Arctic | Artemisia senjavinensis | - | 7 | RT |
| Sage, big red | Salvia penstemonoides | - | 2 | SC |
| Sage, Blodgett's | Salvia blodgettii | - | 4 | RT |
| Sage, Brandegee's | Salvia brandegei | - | 1 | RT |
| Sage, Death Valley | Salvia funerea | - | 1 | RT |
| Sage, desert | Salvia eremostachya | - | 1 | RT |
| Sage, Orocopia | Salvia greatai | - | 1 | SC |
| Sage, Verde Valley | Salvia dorrii mearnsii | - | 2 | SC |
| Sage-grouse, greater | Centrocercus urophasianus | entire | 6 | C |
| Sage-grouse, greater | Centrocercus urophasianus | Columbia basin DPS, WA | 1 | C |
| Sage-grouse, greater | Centrocercus urophasianus | Bi-State | 8 | C |
| Sagebrush, Bolander's | Artemisia cana bolanderi | - | 1 | RT |
| Sagebrush, Coaltown | Artemisia argilosa | - | 6 | RT |
| Sagebrush, Porter | Artemisia porteri | - | 6 | RT |
| sagewort, San Diego | artemisia palmeri | - | 6 | SC |
| Sagittaria, valley | Sagittaria sanfordii | - | 1 | SC |
| Saiga, Mongolian (antelope) | Saiga tatarica mongolica | - | Foreign | E |
| Saiya | Amoreuxia gonzalezii | - | 2 | SC |
| Saki, southern bearded | Chiropotes satanas satanas | - | Foreign | E |
| Saki, white-nosed | Chiropotes albinasus | - | Foreign | E |
| Salamander, Austin blind | Eurycea waterlooensis | - | 2 | C |
| Salamander, Barton Springs | Eurycea sosorum | - | 2 | E |
| salamander, Bay Springs | Plethodon ainsworthi | - | 4 | SU |
| Salamander, Berry Cave | Gyrinophilus gulolineatus | - | 4 | UR |
| salamander, Black-bellied slender | batrachoseps nigriventris | - | 6 | SC |
| Salamander, Breckenridge Mountain slender | Batrachoseps sp. | - | 1 | SC |
| Salamander, Buttercup Creek | Eurycea sp. | Buttercup Creek | 2 | SC |
| Salamander, Caddo Mountain | Plethodon caddoensis | - | 4 | RT |
| Salamander, California tiger | Ambystoma californiense | U.S.A. (CA - Santa Barbara County) | 8 | E |
| Salamander, California tiger | Ambystoma californiense | U.S.A. (CA - Sonoma County) | 8 | E |
| Salamander, California tiger | Ambystoma californiense | U.S.A. (Central CA DPS, not including Santa Barbara and Sonoma DPS) | 8 | T |
| Salamander, Cascade Caverns | Eurycea latitans | - | 2 | RT |
| salamander, Cascade torrent | rhyacotriton cascadae | - | 6 | SC |
| Salamander, Channel Islands slender | Batrachoseps pacificus pacificus | - | 1 | SC |
| Salamander, Cheat Mountain | Plethodon nettingi | - | 5 | T |
| Salamander, Chinese giant | Andrias davidianus (=davidianus d.) | - | Foreign | E |
| Salamander, Coeur d'Alene | Plethodon idahoensis | - | 1 | RT |
| salamander, Columbia torrent | rhyacotriton kezeri | - | 6 | SC |
| Salamander, Comal blind | Eurycea tridentifera | - | 2 | UR |
| Salamander, Cow Knob | Plethodon punctatus | - | 5 | SC |
| Salamander, dark-sided | Eurycea aquatica | - | 4 | SC |
| Salamander, Del Norte | Plethodon elongatus | - | 1 | SC |
| Salamander, desert slender | Batrachoseps aridus | - | 8 | E |
| salamander, Dunn's | plethodon dunni | - | 6 | SC |
| Salamander, Fourche Mountain | Plethodon fourchensis | - | 4 | RT |
| Salamander, frosted flatwoods | Ambystoma cingulatum | - | 4 | T |
| Salamander, Georgetown | Eurycea naufragia | - | 2 | C |
| Salamander, Georgia blind | Haideotriton wallacei | - | 4 | SC |
| Salamander, green | Aneides aeneus | - | 4 | SC |
| Salamander, Inyo Mountains slender | Batrachoseps campi | - | 1 | SC |
| Salamander, Japanese giant | Andrias japonicus (=davidianus j.) | - | Foreign | E |
| Salamander, Jemez Mountains | Plethodon neomexicanus | - | 2 | UR |
| Salamander, Jollyville Plateau | Eurycea tonkawae | - | 2 | C |
| Salamander, Junaluska | Eurycea junaluska | - | 4 | RT |
| Salamander, Kern Canyon slender | Batrachoseps simatus | - | 1 | SC |
| Salamander, Larch Mountain | Plethodon larselli | - | 1 | UR |
| Salamander, limestone | Hydromantes brunus | - | 1 | SC |
| Salamander, Louisiana Slimy | Plethodon kisatchie | - | 4 | SC |
| Salamander, Mount Lyell | Hydromantes platycephalus | - | 1 | SC |
| salamander, Northwestern | ambystoma gracile | - | 7 | SC |
| Salamander, Oklahoma | Eurycea tynerensis | - | 2 | RT |
| Salamander, Olympic torrent | Rhyacotriton olympicus | - | 1 | SU |
| Salamander, Oregon slender | Batrachoseps wrighti | - | 1 | SU |
| Salamander, Ouachita dusky | Desmognathus brimleyorum | - | 4 | SC |
| Salamander, Owens Valley web-toes | Hydromantes sp. | - | 1 | SC |
| salamander, Pacific giant | dicamptodon tenebrosus | - | 6 | SC |
| Salamander, Peaks of Otter | Plethodon hubrichti | - | 5 | SC |
| salamander, Pygmy | Desmognathus wrighti | - | 4 | SC |
| Salamander, Red Hills | Phaeognathus hubrichti | - | 4 | T |
| Salamander, relictual slender | Batrachoseps relictus | - | 1 | SC |
| salamander, Reticulated flatwoods | Ambystoma bishopi | - | 4 | E |
| Salamander, Rich Mountain | Plethodon ouachitae | - | 4 | RT |
| Salamander, robust blind | Typhlomolge robusta | - | 2 | RT |
| Salamander, Sacramento mountain | Aneides hardii | - | 2 | SC |
| Salamander, Salado | Eurycea chisholmensis | - | 2 | C |
| Salamander, San Marcos | Eurycea nana | - | 2 | T |
| Salamander, San Marcos | Eurycea nana | San Marcos salamanders are found in the springflow dominated section of Spring Lake and nearby habitats immediately downstream of the dam forming Spring Lake | 2 | T |
| Salamander, Santa Cruz long-toed | Ambystoma macrodactylum croceum | - | 8 | E |
| Salamander, Scott Bar | Plethodon asupak | - | 1 | RT |
| Salamander, seepage | Desmognathus aeneus | - | 4 | SC |
| Salamander, Shasta | Hydromantes shastae | - | 1 | SC |
| Salamander, Shenandoah | Plethodon shenandoah | - | 5 | E |
| Salamander, Siskiyou Mountains | Plethodon stormi | - | 8 | RT |
| Salamander, Sonora tiger | Ambystoma tigrinum stebbinsi | - | 2 | E |
| Salamander, southern dusky | Desmognatus auriculatus | - | 4 | SU |
| Salamander, southern torrent | Rhyacotriton variegatus | - | 1 | RT |
| Salamander, Techachapi slender | Batrachoseps stebbinsi | - | 1 | UR |
| Salamander, Tennessee cave | Gyrinophilus palleucus | - | 4 | SC |
| Salamander, Texas | Eurycea neotenes | - | 2 | UR |
| Salamander, Texas blind | Typhlomolge rathbuni | - | 2 | E |
| Salamander, Valdina Farms | Eurycea troglodytes | - | 2 | RT |
| salamander, Van Dyke's | plethodon vandykei | - | 6 | SC |
| Salamander, West Virginia spring | Gyrinophilus subterraneus | - | 5 | SC |
| salamander, Western redback | plethodon vehiculum | - | 6 | SC |
| Salmon, Atlantic | Salmo salar | U.S.A. ME Gulf of Maine Atlantic Salmon Distinct Population Segment, which includes all naturally reproducing wild populations and those river-specific hatchery populations of Atlantic salmon having historical, river-specific characteristics found north of and including tributaries of the lower Kennebec River to, but not including, the mouth of the St. Croix River at the U.S.-Canda border. To date, the Services have determined that these populations are found in the Dennys, East Machias, Machias, Pleasant, Narraguagus, Sheepscot, and Ducktrap Rivers and in Cove Brook, Maine | 5 | E |
| Salmon, Atlantic | Salmo salar | Kennebec River DPS | 5 | E |
| Salmon, chinook | Oncorhynchus (=Salmo) tshawytscha | Snake R. (U.S.A._ID,OR,WA) mainstem and the following subbasins_Tucannon R., Grande Ronde R., Imnaha R., and Salmon R.; spring/summer run, natural population(s), wherever found | NMFS | T |
| Salmon, chinook | Oncorhynchus (=Salmo) tshawytscha | Sacramento R. (U.S.A._CA) winter run, wherever found | NMFS | E |
| Salmon, chinook | Oncorhynchus (=Salmo) tshawytscha | U.S.A.(OR, WA) all naturally spawned populations from the Columbia R. and its tributaries upstream from its mouth to a point east of the Hood R. and White Salmon R. to Willamette Falls in Oregon, excluding the spring run in the Clackamas R. | NMFS | T |
| Salmon, chinook | Oncorhynchus (=Salmo) tshawytscha | U.S.A.(CA) from Redwood Creek south to Russian R., inclusive, all naturally spawned populations in mainstems and tributaries | NMFS | T |
| Salmon, chinook | Oncorhynchus (=Salmo) tshawytscha | U.S.A.(OR) all naturally spawned populations in the Clackamas R. and the Willamette R. and its tributaries above Willamette Falls | NMFS | T |
| Salmon, chinook | Oncorhynchus (=Salmo) tshawytscha | U.S.A.(CA) all naturally spawned spring-run populations from the Sacramento San Joaquin R. mainstem and its tributaries | NMFS | T |
| Salmon, chinook | Oncorhynchus (=Salmo) tshawytscha | U.S.A.(WA) all naturally spawned populations in the Columbia R. tributaries upstream of Rock Island Dam and downstream of Chief Joseph Dam, excluding the Okanogan R., and the Columbia R. from a line between the west end of Clatsop jetty, OR, and the west end of Peacock jetty, WA, upstream to Chief Joseph Dam, including spring-run hatchery stocks (and their progeny) in Chiwawa R., Methow R., Twisp R., Chewuch R., White R., and Nason Creek | NMFS | E |
| Salmon, chinook | Oncorhynchus (=Salmo) tshawytscha | U.S.A.(WA) all naturally spawned populations from rivers and streams flowing into Puget Sound, including the Straits of Juan De Fuca from the Elwha R. eastward, and Hood Canal, South Sound, North Sound and the Strait of Georgia | NMFS | T |
| Salmon, chinook | Oncorhynchus (=Salmo) tshawytscha | Snake R. (U.S.A._ID, OR, WA) mainstem and the following subbasins_Tucannon R., Grande Ronde R., Imnaha R., Salmon R, and Clearwater R.; fall run, natural population(s), wherever found | NMFS | T |
| Salmon, chum | Oncorhynchus (=Salmo) keta | U.S.A. (OR, WA) all naturally spawned populations in the Columbia R. and its tributaries | NMFS | T |
| Salmon, chum | Oncorhynchus (=Salmo) keta | U.S.A. (WA) all naturally spawned summer-run populations in Hood Canal and its tributaries and Olympic Penninsula rivers between Hood Canal and Dungeness Bay | NMFS | T |
| Salmon, coho | Oncorhynchus (=Salmo) kisutch | U.S.A. (OR), natural populations in Oregon coastal drainages between Cape Blanco and the Columbia River | NMFS | PT |
| Salmon, coho | Oncorhynchus (=Salmo) kisutch | U.S.A. (natural populations in river basins between Cape Blanco in Curry County, OR and Punta Gorda in Humboldt Co., CA) | NMFS | T |
| Salmon, coho | Oncorhynchus (=Salmo) kisutch | Lower Columbia River | NMFS | T |
| Salmon, coho | Oncorhynchus (=Salmo) kisutch | U.S.A. (CA), naturally spawning populations in streams between Punta Gorda, Humboldt Co., CA and the San Lorenzo River, Santa Cruz, Co., CA | NMFS | E |
| Salmon, sockeye | Oncorhynchus (=Salmo) nerka | Lake Sammamish and Lake Washington | 1 | UR |
| Salmon, sockeye | Oncorhynchus (=Salmo) nerka | U.S.A. (WA) all naturally spawned population in Ozette Lake and its tributary streams | NMFS | T |
| Salmon, sockeye | Oncorhynchus (=Salmo) nerka | U.S.A. (Snake River, ID stock wherever found.) | NMFS | E |
| saltbrush, Lesser | atriplex minuscula | - | 6 | SC |
| Saltbush, Bakersfield | Atriplex tularensis | - | 1 | SC |
| saltbush, Coulter's | Atriplex coulteri | - | 1 | SC |
| Saltbush, Griffith's | Atriplex griffithsii | - | 2 | RT |
| Saltbush, Kleberg's | Atriplex klebergorum | - | 2 | RT |
| Saltbush, Lost Hills | Atriplex vallicola | - | 1 | SC |
| saltbush, Sacramento | Atriplex persistens | - | 1 | SU |
| Saltbush, south coast | Atriplex pacifica | - | 1 | SC |
| saltscale, Davidson's | atriplex serenana var. davidsonii | - | 6 | SC |
| Sand aster, Del Mar | Corethrogyne filaginifolia linifolia | - | 1 | RT |
| Sand grass, [unnamed] | Calamovilfa arcuata | - | 4 | SC |
| Sand grass, [unnamed] | Calamovilfa brevipilis | - | 4 | RT |
| Sand grass, [unnamed] | Calamovilfa brevipilis calvipes | - | 5 | RT |
| Sand grass, [unnamed] | Calamovilfa curtissii | - | 4 | SC |
| Sand-verbena, large-fruited | Abronia macrocarpa | - | 2 | E |
| Sand-verbena, pink | Abronia umbellata breviflora | - | 1 | SC |
| Sand-verbena, Ramshaw Meadows | Abronia alpina | - | 8 | C |
| Sand-verbena, rose-purple | Abronia umbellata acutalata | - | 1 | SC |
| Sand-verbena, [unnamed] | Abronia ammphila | - | 6 | SC |
| Sand-verbena, [unnamed] | Abronia bigelovii | - | 2 | RT |
| Sand-verbena, [unnamed] | Abronia orbiculata | - | 1 | RT |
| Sandalwood, Lanai (=`iliahi) | Santalum freycinetianum var. lanaiense | - | 1 | E |
| Sandfood | Pholisma sonorae | - | 1 | SC |
| Sandlace | Polygonella myriophylla | - | 4 | E |
| Sandmat, pineland | Chamaesyce deltoidea pinetorum | - | 4 | C |
| Sandpaperplant, Death Valley | Petalonyx thurberi gilmanii | - | 1 | SC |
| sandshell, Southern | Hamiota (=Lampsilis) australis | - | 4 | C |
| Sandwort, Alabama | Arenaria alabamensis | - | 4 | RT |
| Sandwort, Bear Valley | Arenaria ursina | - | 8 | T |
| Sandwort, Cumberland | Arenaria cumberlandensis | - | 4 | E |
| Sandwort, Forest Camp | Arenaria macradenia kuschei | - | 1 | SC |
| Sandwort, Howell's | Arenaria howellii | - | 1 | RT |
| Sandwort, Livermore | Arenaria livermorensis | - | 2 | SC |
| Sandwort, Marsh | Arenaria paludicola | - | 8 | E |
| Sandwort, peanut | Minuartia rosei | - | 1 | RT |
| Sandwort, The Lassics | Minuartia decumbens | - | 1 | SC |
| Sanicle, adobe | Sanicula maritima | - | 1 | SC |
| Sanicle, Hoffman's | Sanicula hoffmannii | - | 1 | RT |
| Sanicle, Peck's | Sanicula peckiana | - | 1 | RT |
| Sanicle, rock | Sanicula saxatilis | - | 1 | SC |
| Sanicle, Tracy's | Sanicula tracyi | - | 1 | SC |
| Sapsucker, Williamson's | Sphyrapicus thyroideus | - | 1 | SC |
| sapsucker, Yellow-bellied | sphyrapicus varius | - | 4 | SC |
| Savory, San Miguel | Calamintha chandleri | - | 1 | RT |
| savory, San Miguel | clinopodium chandleri | - | 6 | SC |
| Sawfish, smalltooth | Pristis pectinata | - | NMFS | E |
| Saxifrage, Aleutian | Saxifraga aleutica | - | 7 | RT |
| Saxifrage, Forbes | Saxifraga forbesii | - | 3 | RT |
| Saxifrage, Gray's | Saxifraga caroliniana | - | 5 | SC |
| Saxifrage, Saddle Mountain | Saxifraga hitchcockii | - | 1 | SC |
| Saxifrage, [unnamed] | Saxifraga careyana | - | 4 | RT |
| Saytr, Yontocket | Coenonympha tullia yontockett | - | 1 | RT |
| Scalebroom, gypsum | Lepidospartum burgessii | - | 2 | SC |
| Scarab, Andrews' dune | Pseudocotalpa andrewsi | entire | 8 | RT |
| Scarab, aphodius tortoise commensal | Aphodius troglodytes | - | 4 | SC |
| Scarab, Archbold anomalan | Anomala eximia | - | 4 | SC |
| Scarab, Big Dune aphodius | Aphodius sp. | Big Dune | 1 | SC |
| Scarab, bumblebee | Lichnanthe ursina | - | 1 | SC |
| Scarab, caracara commensal | Trox howelli | - | 4 | SC |
| Scarab, Ciervo aegialian | Aegialia concinna | - | 1 | SC |
| Scarab, copris tortoise commensal | Copris gopheri | - | 4 | SC |
| Scarab, Crescent Dune aegialian | Aegialia crescenta | - | 8 | UR |
| Scarab, Crescent Dune aphodius | Aphodius sp. | Crescent Dune | 1 | SC |
| Scarab, Crescent Dunes serican | Serica ammomensico | Crescent Dune | 8 | UR |
| Scarab, exiguous anomalan | Anomala exigua | - | 4 | SC |
| Scarab, Ford's aphodius | Aphodius fordi | - | 4 | SC |
| Scarab, Frost's spring serican | Serica frosti | - | 4 | SC |
| Scarab, Giuliani's dune | Pseudocotalpa giulianii | - | 8 | UR |
| Scarab, Hardy's aegialian | Aegialia hardyi | - | 8 | UR |
| Scarab, Kelso Dune glaresis | Glaresis arenata | - | 1 | SC |
| Scarab, large aegialian | Aegialia magnifica | - | 8 | UR |
| Scarab, Miami roundhead | Cyclocephala miamiensis | - | 4 | SC |
| Scarab, Ocala burrowing | Peltotrupes youngi | - | 4 | SC |
| Scarab, Onthophagus tortoise commensal | Onthophagus polyphemi | - | 4 | SC |
| Scarab, Sand Mountain aphodius | Aphodius sp. | Sand Mt. | 1 | SC |
| Scarab, Sand Mountain serican | Serica psammobunus | - | 8 | UR |
| Scarab, Scrub Island burrowing | Mycotrupes pedester | - | 4 | SC |
| Scarab, scrub palmetto flower | Trigonopelastes floridana | - | 4 | SC |
| Scarab, spiny Florida sandhill | Gronocarus multispinosus | - | 4 | SC |
| Scarab, tantula serican | Serica tantula | - | 4 | SC |
| Scarab, tibial | Anomala tibialis | - | 2 | SC |
| Scarab, white sand bear | Lichnanthe albopilosa | - | 1 | SC |
| Scarab, Wooly Gulf dune | Polylamina pubescens | - | 4 | SC |
| Scaup, lesser | Aythya affinis | - | 4 | SC |
| Schiedea, Diamond Head | Schiedea adamantis | - | 1 | E |
| Sclerocactus, sp. nov. ined. | Sclerocactus sp. | - | 6 | RT |
| Scorpion, Monterey Dunes | Pauroctonus maritimus | - | 1 | SC |
| Screwstem, Texas | Bartonia texana | - | 2 | RT |
| Scrub-bird, noisy | Atrichornis clamosus | - | Foreign | E |
| scrub-jay, Florida | Aphelocoma coerulescens | - | 4 | T |
| Sculpin Bear Lake | Cottus extensus | - | 6 | SC |
| Sculpin, bluestone | Cottus sp. | - | 5 | SC |
| Sculpin, grotto | Cottus sp. | - | 3 | C |
| Sculpin, Malheur mottled | Cottus bairdi ssp. | - | 1 | SC |
| Sculpin, margined | Cottus marginatus | - | 1 | SC |
| Sculpin, pygmy | Cottus paulus (=pygmaeus) | - | 4 | T |
| Sculpin, rough | Cottus asperrimus | - | 1 | SC |
| Sculpin, shoshone | Cottus greenei | - | 1 | UR |
| Sculpin, slender | Cottus tenuis | - | 1 | SC |
| Sculpin, Wood River | Cottus leiopomus | - | 1 | SC |
| Scurf-pea, Rydberg's | Pediomelum humile | - | 2 | SC |
| Scurf-pea, three-nerved | Pediomelum pentaphyllum | - | 2 | UR |
| Scurf-pea, [unnamed] | Pediomelum castoreum | - | 1 | SC |
| Scurf-pea, [unnamed] | Pediomelum epipsilum | - | 6 | SC |
| Scurf-pea, [unnamed] | Psoralea macrophylla | - | 4 | SC |
| Scurfpea, bigleaf | Orbexilum macrophyllum | - | 4 | RT |
| Sea turtle, green | Chelonia mydas | Wherever found except where listed as endangered | 4 | T |
| Sea turtle, green | Chelonia mydas | Breeding colony populations in FL and on Pacific coast of Mexico | 4 | E |
| Sea turtle, hawksbill | Eretmochelys imbricata | - | 4 | E |
| Sea turtle, Kemp's ridley | Lepidochelys kempii | - | 2 | E |
| Sea turtle, leatherback | Dermochelys coriacea | - | 4 | E |
| Sea turtle, loggerhead | Caretta caretta | Western North Atlantic population | 4 | PT |
| Sea turtle, loggerhead | Caretta caretta | North Pacific population | 4 | UR |
| Sea turtle, loggerhead | Caretta caretta | - | 4 | T |
| Sea turtle, olive ridley | Lepidochelys olivacea | Breeding colony populations on Pacific coast of Mexico | 4 | E |
| Sea turtle, olive ridley | Lepidochelys olivacea | Wherever found except where listed as endangered | 4 | T |
| Sea-lavender, [unnamed] | Limonium carolinianum angustatum | - | 4 | RT |
| Sea-lion, Steller | Eumetopias jubatus | Population segment west of 1440 W. Long | NMFS | E |
| Sea-lion, Steller | Eumetopias jubatus | Entire, except the population segment west of 1440 W. Long | NMFS | T |
| Sea-purslane, roughseed | Sesuvium trianthemoides | - | 2 | SC |
| Seablite, California | Suaeda californica | - | 8 | E |
| seablite, Woolly | suaeda taxifolia | - | 6 | SC |
| Seagrass, Johnson's | Halophila johnsonii | - | NMFS | T |
| Seal, Caribbean monk | Monachus tropicalis | - | NMFS | E |
| Seal, Guadalupe fur | Arctocephalus townsendi | - | NMFS | T |
| Seal, Hawaiian monk | Monachus schauinslandi | - | NMFS | E |
| Seal, Mediterranean monk | Monachus monachus | - | NMFS | E |
| Seal, Saimaa | Phoca hispida saimensis | - | NMFS | E |
| Sebucan, [unnamed] | Cereus quadricostatus | - | 4 | RT |
| Sedge, Anderson | Carex jacobi-peteri | - | 7 | RT |
| Sedge, Aroostook | Carex elachycarpa | - | 5 | RT |
| Sedge, Barratt's | Carex barrattii | - | 5 | RT |
| Sedge, Biltmore | Carex biltmoreana | - | 4 | RT |
| Sedge, Chapman's | Carex chapmanii | - | 4 | SC |
| Sedge, flat dune | Cyperus onerosus | - | 2 | SC |
| Sedge, golden | Carex lutea | - | 4 | E |
| Sedge, Indian Valley | Carex aboriginum | - | 1 | RT |
| Sedge, Josselyn's | Carex josselynii | - | 5 | RT |
| Sedge, Manhart's | Carex manhartii | - | 4 | SC |
| Sedge, Navajo | Carex specuicola | - | 2 | T |
| Sedge, San Luis | Carex obispoensis | - | 1 | RT |
| Sedge, Sierra | Carex paucifructus | - | 1 | RT |
| Sedge, small-living, thick-nerved | Carex microptera crassinervia | - | 6 | RT |
| Sedge, Thompkins' | Carex tompkinsii | - | 1 | RT |
| Sedge, tissue | Carex hyalina | - | 2 | SC |
| Sedge, umbrella | Cyperus grayoides | - | 3 | SC |
| Sedge, variable | Carex polymorpha | - | 5 | SC |
| Sedge, waterfall's | Carex latebracteata | - | 2 | SC |
| Sedge, white | Carex albida | - | 8 | E |
| Sedge, Whitney | Carex whitneyi | - | 1 | RT |
| Sedge, [unnamed] | Carex arapahoensis | - | 6 | RT |
| Sedge, [unnamed] | Carex austrocaroliniana | - | 4 | RT |
| Sedge, [unnamed] | Carex baltzellii | - | 4 | SC |
| Sedge, [unnamed] | Carex bicknellii opaca | - | 4 | SC |
| Sedge, [unnamed] | Carex communis amplisquama | - | 4 | SC |
| Sedge, [unnamed] | Carex decomposita | - | 3 | RT |
| Sedge, [unnamed] | Carex fissa | - | 2 | SC |
| Sedge, [unnamed] | Carex formosa | - | 3 | SC |
| Sedge, [unnamed] | Carex haysii | - | 6 | SC |
| Sedge, [unnamed] | Carex impressinervia | - | 4 | SC |
| Sedge, [unnamed] | Carex interrupta | - | 1 | RT |
| Sedge, [unnamed] | Carex lenticularis dolia | - | 7 | SC |
| Sedge, [unnamed] | Carex misera | - | 4 | RT |
| Sedge, [unnamed] | Carex onusta | - | 2 | RT |
| Sedge, [unnamed] | Carex oronensis | - | 5 | SC |
| Sedge, [unnamed] | Carex parryana idahoa | - | 1 | RT |
| Sedge, [unnamed] | Carex purpurifera | - | 4 | RT |
| Sedge, [unnamed] | Carex roanensis | - | 4 | SC |
| Sedge, [unnamed] | Carex schweinitzii | - | 5 | SC |
| Sedge, [unnamed] | Carex scirpoidea curatorum | - | 2 | RT |
| Sedge, [unnamed] | Carex socialis | - | 4 | RT |
| Sedge, [unnamed] | Cyperus louisianensis | - | 4 | SC |
| Seed bug, Bryan's oceanides | Oceanides bryani | - | 1 | SC |
| Seed bug, French Frigate Shoal | Nysius frigatensis | - | 1 | SC |
| Seed bug, Fullaway's | Nysius fullawayi | - | 1 | SC |
| Seed bug, Kauai band-legged | Neseis alternatus | - | 1 | SC |
| Seed bug, Mauna Loa metrargan | Metrarga obscura | - | 1 | SC |
| Seed bug, Mt. Haleakala | Neseis haleakalae | - | 1 | SC |
| Seed bug, Necker bunchgrass | Nysius suffusus | - | 1 | SC |
| Seed bug, Necker goosefoot | Nysius neckerensis | - | 1 | SC |
| Seed bug, Nihoa nysius | Nysius nihoae | - | 1 | SC |
| Seed bug, Perkins' oceanides | Oceanides perkinsi | - | 1 | SC |
| Seed bug, rough-headed oceanides | Oceanides rugosiceps | - | 1 | SC |
| Seed bug, Villosan flightless | Nesocryptias villosa | - | 1 | SC |
| Seedeater, Tumaco | Sporophila insulata | - | NA | SU |
| Seepweed, hardtoe | Suaeda duripes | - | 2 | SC |
| Seledang | Bos gaurus | - | Foreign | E |
| Selenia, Jones' | Selenia jonesii | - | 2 | RT |
| Semaphore grass, northcoast | Pleuropogon hooverianus | - | 1 | SC |
| Semaphore grass, Oregon | Pleuropogon oregonus | - | 1 | SC |
| Senna, Ripley's | Senna ripleyana | - | 2 | SC |
| Serow | Naemorhedus (=Capricornis) sumatraensis | - | Foreign | E |
| Serval, Barbary | Leptailurus (=Felis) serval constantina | - | Foreign | E |
| Service-berry, [unnamed] | Amelanchier nantucketensis | - | 5 | SC |
| Shagreen, Magazine Mountain | Mesodon magazinensis | - | 4 | T |
| Shama, Cebu black (thrush) | Copsychus niger cebuensis | - | Foreign | E |
| Shapo | Ovis vignei vignei | - | Foreign | E |
| Shearwater, Heinroth's | Puffinus heinrothi | - | Foreign | T |
| Shearwater, Newell's Townsend's | Puffinus auricularis newelli | - | 1 | T |
| Sheep, bighorn | Ovis canadensis | - | 8 | SC |
| Sheep, Peninsular bighorn | Ovis canadensis nelsoni | U.S.A. (CA) Peninsular Ranges | 8 | E |
| Sheep, Sierra Nevada bighorn | Ovis canadensis sierrae | U.S.A. (CA) Sierra Nevada | 8 | E |
| Shield bug, Koa | Coleotichus blackburniae | - | 1 | SC |
| Shiner, Altamaha | Notropis xaenurus | - | 4 | SC |
| Shiner, Arkansas River | Notropis girardi | Arkansas River Basin (AR, KS, NM, OK, TX) | 2 | T |
| Shiner, beautiful | Cyprinella formosa | - | 2 | T |
| Shiner, blackmouth | Notropis melanostomus | - | 4 | SC |
| Shiner, blue | Cyprinella caerulea | - | 4 | T |
| Shiner, bluestripe | Cyprinella callitaenia | - | 4 | SC |
| Shiner, broadstripe | Pteronotropis euryzonus | - | 4 | SC |
| Shiner, burrhead | Notropis asperifrons | - | 4 | RT |
| Shiner, Cahaba | Notropis cahabae | - | 4 | E |
| Shiner, Cape Fear | Notropis mekistocholas | - | 4 | E |
| Shiner, Chihuahua | Notropis chihuahua | - | 2 | SC |
| Shiner, colorless | Notropis perpallidus | - | 2 | RT |
| Shiner, highscale | Notropis hypsilepis | - | 4 | SC |
| Shiner, Maravillas red | Cyprinella lutrensis blairi | - | 2 | RT |
| Shiner, Ocmulgee | Cyprinella callisema | - | 4 | SC |
| Shiner, Ouachita Mountain | Lythrurus snelsoni | - | 2 | SC |
| Shiner, Ozark | Notropis ozarcanus | - | 4 | SC |
| Shiner, palezone | Notropis albizonatus | - | 4 | E |
| Shiner, Pecos bluntnose | Notropis simus pecosensis | - | 2 | T |
| Shiner, phantom | Notropis orca | - | 2 | RT |
| Shiner, proserpine | Cyprinella proserpina | - | 2 | SC |
| Shiner, Rio Grande | Notropis jemezanus | - | 2 | SC |
| Shiner, Rio Grande bluntnose | Notropis simus simus | - | 2 | RT |
| Shiner, roughhead | Notropis semperasper | - | 5 | SC |
| Shiner, sharpnose | Notropis oxyrhynchus | - | 2 | C |
| Shiner, smalleye | Notropis buccula | - | 2 | C |
| Shiner, Topeka | Notropis topeka (=tristis) | - | 6 | E |
| Shoal sprite | Amphigyra alabamensis | - | 4 | SC |
| Shootingstar, French's | Dodecatheon frenchii | - | 3 | RT |
| Shootingstar, Tundra | Dodecatheon austrofrigidum | - | 1 | SC |
| Shore fly, Wilbur Springs | Paracoenia calida | - | 1 | SC |
| Shou | Cervus elaphus wallichi | - | Foreign | E |
| Shoulderband, Bridges' Coast Range | Helminthoglypta nickliniana bridgesi | - | 1 | SC |
| Shoulderband, Kern | Helminthoglypta callistoderma | - | 1 | SC |
| Shoulderband, Merced Canyon | Helminthoglypta allynsmithi | - | 1 | SC |
| Shoulderband, Peninsula Coast Range | Helminthoglypta nickliniana awania | - | 1 | SC |
| Shoulderband, Peninsular Range | Helminthoglypta traski coelata | - | 1 | SC |
| Shoulderband, Pomo bronze | Helminthoglypta arrosa pomoensis | - | 1 | SC |
| Shoulderband, redwood | Helminthoglypta sequoicola consors | - | 1 | SC |
| Shoulderband, Victorville | Helminthoglypta mohaveena | - | 1 | SC |
| Shoulderband, Williams' bronze | Helminthoglypta arrosa williamsi | - | 1 | SC |
| Shrew, Aransas short-tailed | Blarina hylophaga plumbea | - | 2 | SC |
| Shrew, Arizona | Sorex arizonae | - | 2 | SC |
| Shrew, Arizona water | Sorex palustris navigator | - | 2 | RT |
| Shrew, Ashland | Sorex trigonirostris | - | 1 | RT |
| Shrew, Buena Vista Lake ornate | Sorex ornatus relictus | - | 8 | E |
| Shrew, Destruction Island | Sorex trowbridgii destructioni | - | 1 | SC |
| Shrew, Dismal Swamp short-tailed | Blarina brevicauda telmalestes | - | 4 | RT |
| Shrew, Dismal Swamp southeastern | Sorex longirostris fisheri | - | 5 | DP |
| Shrew, Glacier Bay water | Sorex alaskanus | - | 7 | SC |
| Shrew, Homossassa | Sorex longirostris eionis | - | 4 | RT |
| Shrew, long-tailed | Sorex dispar | - | 5 | RT |
| Shrew, Martha's Vineyard short-tailed | Blarina brevicauda aloga | - | 5 | RT |
| Shrew, Monterey ornate | Sorex ornatus salarius | - | 1 | SC |
| Shrew, Mt. Lyell | Sorex lyelli | - | 1 | RT |
| Shrew, Nantucket short-tailed | Blarina brevicauda compacta | - | 5 | SC |
| Shrew, northeastern pygmy | Microsorex hoyi thompsoni | - | 5 | RT |
| Shrew, Preble's | Sorex preblei | - | 6 | SC |
| Shrew, Pribilof Islands | Sorex hydrodromus | - | 7 | SC |
| Shrew, salt marsh ornate | Sorex ornatus salicornicus | - | 1 | SC |
| Shrew, salt marsh vagrant | Sorex vagrans halicoetes | - | 1 | SC |
| Shrew, San Bernardino dusky | Sorex monticolus parvidens | - | 1 | RT |
| Shrew, Santa Catalina ornate | Sorex ornatus willetti | - | 1 | SC |
| Shrew, Sherman's short-tailed | Blarina brevicauda shermani | - | 4 | SC |
| Shrew, southern pygmy | Sorex hoyi winnemana | - | 5 | RT |
| Shrew, southern water | Sorex palustris punctulatus | - | 5 | SC |
| Shrew, Suisun ornate | Sorex ornatus sinuosus | - | 1 | SC |
| Shrew, Tuckahoe masked | Sorex cinereus nigriculus | - | 5 | SC |
| shrike, Island loggerhead | Lanius ludovicianus ssp. anthonyi | entire | 8 | SU |
| Shrike, Loggerhead | Lanius ludovicianus | - | 1 | SC |
| Shrike, migrant loggerhead | Lanius ludovicianus migrans | - | 3 | SC |
| Shrike, San Clemente loggerhead | Lanius ludovicianus mearnsi | - | 8 | E |
| Shrimp, Alabama cave | Palaemonias alabamae | - | 4 | E |
| Shrimp, anchialine pool | Antecaridina lauensis | - | 1 | RT |
| Shrimp, anchialine pool | Calliasmata pholidota | - | 1 | RT |
| Shrimp, anchialine pool | Metabetaeus lohena | - | 1 | C |
| Shrimp, anchialine pool | Palaemonella burnsi | - | 1 | C |
| Shrimp, anchialine pool | Procaris hawaiana | - | 1 | C |
| Shrimp, anchialine pool | Vetericaris chaceorum | - | 1 | C |
| Shrimp, California freshwater | Syncaris pacifica | - | 8 | E |
| Shrimp, Kentucky cave | Palaemonias ganteri | - | 4 | E |
| shrimp, Midvalley fairy | branchinecta | - | 6 | SC |
| Shrimp, Midvalley Fairy | Branchinecta mesovallensis | - | 1 | RT |
| Shrimp, Squirrel Chimney Cave | Palaemonetes cummingi | - | 4 | T |
| Shrimp, Texas cave | Palaemonetes antrorum | - | 2 | SC |
| Shrimp, troglobitic groundwater | Typhlatya monae | - | 4 | RT |
| Shrimp, [unnamed] | Halocaridina palahemo | - | 1 | SC |
| Siamang | Symphalangus syndactylus | - | Foreign | E |
| Sidalcea, Butte County | Sidalcea robusta | - | 1 | SC |
| Sidalcea, Cuesta Pass | Sidalcea hickmanii anomala | - | 1 | SC |
| Sidalcea, Hickman's | Sidalcea hickmanii hickmanii | - | 1 | RT |
| Sideband, Button's Sierra | Monadenia mormonum buttoni | - | 1 | SC |
| Sideband, Dalles | Monadenia fidelis minor | - | 1 | UR |
| Sideband, hirsute sierra | Monadenia mormonum hirsuta | - | 1 | SC |
| Sideband, keeled | Monadenia circumcarinata | - | 1 | SC |
| Sideband, Rocky coast Pacific | Monadenia fidelis pronotis | - | 1 | RT |
| sideband, Shasta | Monadenia troglodytes troglodytes | - | 1 | UR |
| sideband, Siskiyou | Monadenia chaceana | - | 8 | SU |
| sideband, Wintu | Monadenia troglodytes ssp. wintu | - | 8 | SU |
| Sideband, Yosemite mariposa | Monadenia hillebrandi yosemitensis | - | 1 | SC |
| Sideswimmer, Yancey | Stygobromus carolinensis | - | 4 | SC |
| sidewinder | crotalinae cerastes | - | 6 | SC |
| Sifakas | Propithecus spp. | - | Foreign | E |
| Siltsnail, crystal | Cincinnatia helicogyra | - | 4 | SC |
| Siltsnail, Enterprise | Cincinnatia monroensis | - | 4 | SC |
| Siltsnail, Ichetucknee | Cincinnatia mica | - | 4 | SC |
| Siltsnail, ponderous | Cincinnatia ponderosa | - | 4 | SC |
| Siltsnail, pygmy | Cincinnatia parva | - | 4 | SC |
| Siltsnail, Seminole | Cincinnatia vanhyningi | - | 4 | SC |
| Siltsnail, Wekiwa | Cincinnatia wekiwae | - | 4 | SC |
| Silverbells, [unnamed] | Styrax platanifolia stellata | - | 2 | RT |
| silverbush, Blodgett's | Argythamnia blodgettii | - | 4 | C |
| Silverling | Paronychia argyrocoma albimontana | - | 5 | RT |
| Silverside, Waccamaw | Menidia extensa | - | 4 | T |
| Silverspot, blue | Speyeria nokomis caerulescens | - | 2 | SC |
| Silverspot, Carole's | Speyeria zerene carolae | - | 1 | SC |
| Silverspot, Carson Valley | Speyeria nokomis carsonensis | - | 8 | UR |
| Silverspot, Great Basin | Speyeria nokomis nokomis | - | 6 | SC |
| Silverspot, Grey's | Speyeria atlantis greyi | - | 1 | SC |
| Silverspot, Tehachapi Mountain | Speyeria egleis tehachapina | - | 1 | SC |
| Silverspot, Willamette | Speyeria callippe extincta | - | 1 | RT |
| Silversword, eke | Argyroxiphium caliginis | - | 1 | SC |
| Silversword, Mauna Loa (=Ka'u) | Argyroxiphium kauense | - | 1 | E |
| Siren, Gulf Hammock dwarf | Pseudobranchus striatus lustricolus | - | 4 | SC |
| Siren, Rio Grande lesser | Siren intermedia texana | - | 2 | SC |
| Sisi | Ostodes strigatus | - | 1 | C |
| Siskin, red | Carduelis cucullata | - | Foreign | E |
| Skeletonplant, Entrada | Lygodesmia entrada | - | 6 | RT |
| Skimmer, Apalachicola twilight | Neurocordulia clara | - | 4 | SC |
| Skimmer, banded bog | Williamsonia lintneri | - | 5 | SC |
| skimmer, Black | rynchops niger | - | 6 | SC |
| Skimmer, Margarita River | Macromia margarita | - | 5 | SC |
| Skimmer, Wabash belted | Macromia wabashensis | - | 3 | SC |
| Skink, Arizona Gilbert's | Eumeces gilberti arizonensis | - | 2 | SC |
| Skink, bluetail mole | Eumeces egregius lividus | - | 4 | T |
| Skink, Cedar Key mole | Eumeces egregius insularis | - | 4 | SC |
| Skink, Coronado | Eumeces skiltonianus interparietalis | - | 1 | SC |
| Skink, Florida Keys mole | Eumeces egregius egregius | - | 4 | SC |
| Skink, Pandanus | Aulacoplax leptosoma | - | 1 | RT |
| Skink, Round Island | Leiolopisma telfairi | - | Foreign | T |
| Skink, sand | Neoseps reynoldsi | - | 4 | T |
| skink, Western red-tailed | eumeces gilberti ssp. rubricaudatus | - | 2 | SC |
| Skipper, alkali | Pseudocopaeodes eunus eunus | - | 1 | UR |
| Skipper, Bay | Euphyes bayensis | - | 4 | UR |
| Skipper, Carson wandering | Pseudocopaeodes eunus obscurus | - | 8 | E |
| Skipper, Chermock's mulberry wing | Poanes massasiot chermocki | - | 5 | SC |
| Skipper, Dakota | Hesperia dacotae | - | 3 | C |
| Skipper, denio sandhill | Polites sabuleti sinemaculata | - | 8 | UR |
| Skipper, dun | Euphyes vestris harbisoni | - | 1 | UR |
| Skipper, eastern beard grass | Atrytone arogos arogos | - | 5 | SC |
| Skipper, grizzled | Pyrgus wyandot | - | 5 | SC |
| Skipper, Laguna Mountains | Pyrgus ruralis lagunae | - | 8 | E |
| Skipper, MacNeill sooty wing | Hesperopsis gracielae | - | 1 | SC |
| Skipper, maculated manfreda | Stallingsia maculosus | - | 2 | SC |
| Skipper, Mardon | Polites mardon | - | 1 | C |
| Skipper, Pawnee montane | Hesperia leonardus montana | - | 6 | T |
| Skipper, Railroad Valley | Hesperia uncas giulianii | - | 8 | UR |
| Skipper, rare | Problema bulenta | - | 4 | SC |
| Skipper, Sonoma arctic | Carterocephalus palaemon ssp. | - | 1 | SC |
| Skipper, Spring Mountain comma | Hesperia comma ssp. | - | 1 | SC |
| Skipper, wandering | Panoquina errans | - | 1 | SC |
| Skipper, White Mountains | Hesperia mirimae ssp. | - | 1 | SC |
| Skipper, White Mountains sandhill | Polites sabuleti albomontana | - | 1 | SC |
| Skistodiaptomus, Carolina | Skistodiaptomus carolinensis | - | 4 | SC |
| Skullcap, Florida | Scutellaria floridana | - | 4 | T |
| Skullcap, heart-leaved, | Scutellaria ovata pseudoarguta | - | 5 | SC |
| Skullcap, large-flowered | Scutellaria montana | - | 4 | T |
| Skullcap, Ravendale | Scutellaria holmgreniorum | - | 1 | RT |
| Skullcap, smooth-stem | Scutellaria laevis | - | 2 | SC |
| Skullcap, Thieret's | Scutellaria thieretii | - | 4 | SC |
| Skullcap, [unnamed] | Scutellaria ocmulgee | - | 4 | SC |
| Skullcap, [unnamed] | Scutellaria saxatilis | - | 3 | RT |
| Skunk, Big Thicket hog-nosed | Conepatus mesoleucus telmalestes | - | 2 | SC |
| Skunk, Channel Islands spotted | Spilogale putorius amphiala | - | 1 | SC |
| Skunk, Colorado hog-nosed | Conepatus mesoleucus figginsi | - | 6 | SC |
| Skunk, Gulf Coast hog-nosed | Conepatus leuconotus texensis | - | 2 | RT |
| Skunk, Plains spotted | Spilogale putorius interrupta | - | 6 | SC |
| Sky-pilot, Mason's | Polemonium chartaceum | - | 1 | RT |
| Skyrocket, Pagosa | Ipomopsis polyantha | - | 6 | PE |
| Slabshell, Chipola | Elliptio chipolaensis | - | 4 | T |
| Slabshell, Neuse | Elliptio judithae | - | 4 | SC |
| Slider, Big Bend | Pseudemys scripta gaigeae | - | 2 | RT |
| Slitmouth, Rich Mt. | Stenotrema pilsbryi | - | 4 | SC |
| Slitshell, excised | Gyrotoma excisa | - | 4 | RT |
| Slitshell, pagoda | Gyrotoma pagoda | - | 4 | RT |
| Slitshell, pyramid | Gyrotoma pyramidata | - | 4 | RT |
| Slitshell, ribbed | Gyrotoma pumila | - | 4 | RT |
| Slitshell, round | Gyrotoma walkeri | - | 4 | RT |
| Slitshell, striate | Gyrotoma lewisi | - | 4 | RT |
| Sloth, Brazilian three-toed | Bradypus torquatus | - | Foreign | E |
| Slug, Santa Barbara shelled | Binneya notabilis | - | 1 | SC |
| Smallheaded fly, Mary Alice's | Eulonchus marialiciae | - | 4 | SC |
| Smelowskia, Mt. Lassen | Smelowskia ovalis congesta | - | 1 | RT |
| Smelt, Columbia River | Thaleichthys pacificus | - | NMFS | RT |
| Smelt, delta | Hypomesus transpacificus | - | 8 | T |
| Smelt, longfin | Spirinchus thaleichthys | - | 8 | UR |
| Smelt, longfin, San Francisco Bay delta population | Spirinchus thaleichthys | San Francisco Bay delta population | 8 | RT |
| Smelt, pygmy | Osmerus spectrum | - | 5 | SC |
| Snaggletooth, shortneck | Gastrocopta dalliana dalliana | - | 2 | SC |
| Snail, Alifan Tree | Partula salifana | - | 1 | SC |
| snail, Aquatic | valvata mergella | - | 8 | SC |
| Snail, Archer's toothed land | Mesodon archeri | - | 4 | RT |
| Snail, armored | Pyrgulopsis (=Marstonia) pachyta | - | 4 | E |
| Snail, Badwater | Assiminea infima | - | 1 | SC |
| Snail, bicolored cactus | Xerarionta tryoni | - | 1 | RT |
| Snail, big-tooth covert | Mesodon jonesianus | - | 4 | RT |
| Snail, Bliss Rapids | Taylorconcha serpenticola | - | 1 | T |
| Snail, boulder | Leptoxis crassa | - | 4 | SC |
| Snail, Briarton Pleistocene | Vertigo briarensis | - | 3 | SC |
| Snail, Cape Mendocino | Helminthoglypta arrosa mattolensis | - | 1 | RT |
| Snail, cathedral | Micrarionta indioensis cathedralis | - | 1 | RT |
| Snail, Chittenango ovate amber | Succinea chittenangoensis | - | 5 | T |
| Snail, dented Peninsula | Helminthoglypta arrosa miwoka | - | 1 | RT |
| Snail, desert springsnail | Pyrgulopsis deserta | - | 6 | RT |
| Snail, Diamond Y Spring | Pseudotryonia (=Tryonia) adamantina | - | 2 | C |
| Snail, Diamond-Y pond | Physella bottomeri | - | 2 | RT |
| Snail, flat-spired three-toothed | Triodopsis platysayoides | - | 5 | T |
| Snail, Florida tree | Liguus fasciatus | - | 4 | RT |
| Snail, fragile tree | Samoana fragilis | - | 1 | C |
| Snail, Gila Tryonia | Tryonia gilae | - | 2 | SC |
| Snail, Guam tree | Partula radiolata | - | 1 | C |
| Snail, Hawai`i tree | Partulina confusa | - | 1 | SC |
| Snail, Hawai`i tree | Partulina horneri | - | 1 | SC |
| Snail, Hawai`i tree | Partulina physa | - | 1 | SC |
| Snail, horseshoe | Micrarionta intercisa | - | 1 | RT |
| Snail, Humped tree | Partula gibba | - | 1 | C |
| Snail, Indiana river | Goniobasis semicarinata indianensis | - | 3 | RT |
| Snail, Iowa Pleistocene | Discus macclintocki | - | 3 | E |
| Snail, Jackson Lake | Helisoma jacksonense | - | 6 | SC |
| Snail, Lanai tree | Partulina crassa | - | 1 | SC |
| Snail, Lanai tree | Partulina semicarinata | - | 1 | C |
| Snail, Lanai tree | Partulina variabilis | - | 1 | C |
| Snail, Langford's tree | Partula langfordi | - | 1 | C |
| Snail, Longstreet Spring | Fluminicola sp. | - | 1 | RT |
| Snail, Manus Island tree | Papustyla pulcherrima | - | Foreign | E |
| Snail, Maui tree | Partulina anceyana | - | 1 | SC |
| Snail, Maui tree | Partulina carnicolor | - | 1 | SC |
| Snail, Maui tree | Partulina crocea | - | 1 | SC |
| Snail, Maui tree | Partulina dolei | - | 1 | SC |
| Snail, Maui tree | Partulina fusoidea | - | 1 | SC |
| Snail, Maui tree | Partulina germana | - | 1 | SC |
| Snail, Maui tree | Partulina gouldii | - | 1 | SC |
| Snail, Maui tree | Partulina grisea | - | 1 | SC |
| Snail, Maui tree | Partulina induta | - | 1 | SC |
| Snail, Maui tree | Partulina kaaeana | - | 1 | SC |
| Snail, Maui tree | Partulina lemmoni | - | 1 | SC |
| Snail, Maui tree | Partulina marmorata | - | 1 | SC |
| Snail, Maui tree | Partulina mutabilis | - | 1 | SC |
| Snail, Maui tree | Partulina natti | - | 1 | SC |
| Snail, Maui tree | Partulina nivea | - | 1 | SC |
| Snail, Maui tree | Partulina perdix | - | 1 | SC |
| Snail, Maui tree | Partulina plumbea | - | 1 | SC |
| Snail, Maui tree | Partulina porcellana | - | 1 | SC |
| Snail, Maui tree | Partulina radiata | - | 1 | SC |
| Snail, Maui tree | Partulina splendida | - | 1 | SC |
| Snail, Maui tree | Partulina tapaniana | - | 1 | SC |
| Snail, Maui tree | Partulina terebra | - | 1 | SC |
| Snail, Maui tree | Partulina thaanumiana | - | 1 | SC |
| Snail, Maui tree | Partulina ustulata | - | 1 | SC |
| Snail, Maui tree | Partulina winniei | - | 1 | SC |
| Snail, Mirey Ridge supercoil | Paravitrea clappi | - | 4 | RT |
| Snail, Moloka`i tree | Partulina dwightii | - | 1 | SC |
| Snail, Moloka`i tree | Partulina mighelsiana | - | 1 | SC |
| Snail, Moloka`i tree | Partulina mucida | - | 1 | SC |
| Snail, Moloka`i tree | Partulina proxima | - | 1 | SC |
| Snail, Moloka`i tree | Partulina redfieldii | - | 1 | SC |
| Snail, Moloka`i tree | Partulina rufa | - | 1 | SC |
| Snail, Moloka`i tree | Partulina subpolita | - | 1 | SC |
| Snail, Moloka`i tree | Partulina tessellata | - | 1 | SC |
| Snail, Moloka`i tree | Partulina theodorei | - | 1 | SC |
| Snail, Morro shoulderband (=Banded dune) | Helminthoglypta walkeriana | - | 8 | E |
| Snail, Mt. Matafao different | Diastole matafaoi | - | 1 | SC |
| Snail, New Mexico Ramshorn | Pecosorbis kansasensis | - | 2 | RT |
| Snail, Newcomb's | Erinna newcombi | - | 1 | T |
| Snail, Newcomb's littorine | Algamorda newcombiana | - | 1 | SC |
| Snail, noonday | Mesodon clarki nantahala | - | 4 | T |
| Snail, Ofu tree | Samoana thurstoni | - | 1 | SC |
| Snail, painted snake coiled forest | Anguispira picta | - | 4 | T |
| Snail, Pecos assiminea | Assiminea pecos | - | 2 | E |
| Snail, Phantom Cave | Cochliopa texana | - | 2 | C |
| Snail, Samoana tree | Samoana conica | - | 1 | SC |
| Snail, San Clemente Island blunt-top | Sterkia clementina | - | 1 | RT |
| Snail, sculpin | Stiobia nana | - | 4 | SC |
| Snail, Short Samoan tree | Somoana abbreviata | - | 1 | SC |
| Snail, small geniculate river | Lithasia pinguis | - | 4 | RT |
| Snail, Snake River physa | Physa natricina | - | 1 | E |
| Snail, Spruce Creek | Melongena sprucecreekensis | - | 4 | RT |
| Snail, Stock Island tree | Orthalicus reses (not incl. nesodryas) | - | 4 | T |
| Snail, tulotoma | Tulotoma magnifica | - | 4 | E |
| Snail, Tutuila tree | Eua zebrina | - | 1 | C |
| Snail, umbilicate river | Leptoxis subglubosa umbilicata | - | 4 | RT |
| Snail, Utah valvata | Valvata utahensis | - | 1 | E |
| Snail, Virginia fringed mountain | Polygyriscus virginianus | - | 5 | E |
| Snail, Virile Amargosa | Undescribed sp. | - | 1 | RT |
| Snail, Waianae tree | Partulina dubia | - | 1 | SC |
| Snail, wreathed cactus | Xerarionta redimita | - | 1 | RT |
| Snail, [unnamed] | Antrorbis breweri | - | 4 | SC |
| Snail, [unnamed] | Catinella gelida | - | 3 | UR |
| Snail, [unnamed] | Diastole schmeltziana | - | 1 | SC |
| Snail, [unnamed] | Laminella sanguinea | - | 1 | SC |
| Snail, [unnamed] | Leptachatina lepida | - | 1 | SC |
| Snail, [unnamed] | Mesodon clausus trossulus | - | 4 | SC |
| Snail, [unnamed] | Neoplanorbis carinatus | - | 4 | SC |
| Snail, [unnamed] | Neoplanorbis smithi | - | 4 | SC |
| Snail, [unnamed] | Neoplanorbis tantillus | - | 4 | SC |
| Snail, [unnamed] | Neoplanorbis umbilicatus | - | 4 | SC |
| Snail, [unnamed] | Neritilia hawaiiensis | - | 1 | SC |
| Snail, [unnamed] | Paravitrea aulacogyra | - | 4 | SC |
| Snail, [unnamed] | Perdicella carinella | - | 1 | SC |
| Snail, [unnamed] | Perdicella fulgurans | - | 1 | SC |
| Snail, [unnamed] | Perdicella helena | - | 1 | SC |
| Snail, [unnamed] | Perdicella kuhnsi | - | 1 | SC |
| Snail, [unnamed] | Perdicella mauiensis | - | 1 | SC |
| Snail, [unnamed] | Perdicella ornata | - | 1 | SC |
| Snail, [unnamed] | Perdicella thwingii | - | 1 | SC |
| Snail, [unnamed] | Perdicella zebra | - | 1 | SC |
| Snail, [unnamed] | Perdicella zebrina | - | 1 | SC |
| Snail, [unnamed] | Succinea guamensis | - | 1 | SC |
| Snail, [unnamed] | Succinea piratarum | - | 1 | SC |
| Snail, [unnamed] | Succinea quadrasi | - | 1 | SC |
| Snail, [unnamed] | Trochomorpha apia | - | 1 | SC |
| Snail, [unnamed] | Valvata virens | - | 1 | SC |
| Snails, Oahu tree | Achatinella spp. | - | 1 | E |
| Snake, Atlantic salt marsh | Nerodia clarkii taeniata | - | 4 | T |
| Snake, Black Hills redbelly | Storeria occipitomaculata pahasapae | - | 6 | SC |
| Snake, black pine | Pituophis melanoleucus lodingi | - | 4 | C |
| Snake, Brazos water | Nerodia harteri harteri | - | 2 | UR |
| snake, California king | lampropeltis getula ssp. californiae | - | 8 | SC |
| Snake, coast patch-nosed | Salvadora hexalepis virgultea | - | 1 | SC |
| Snake, Concho water | Nerodia paucimaculata | - | 2 | T |
| Snake, copperbelly water | Nerodia erythrogaster neglecta | IN north of 400 N. Lat., MI, OH | 3 | T |
| Snake, Culebra garden | Arrhyton exiguum exiguum | - | 4 | SC |
| Snake, desert king | Lampropeltis getulus splendida | - | 2 | RT |
| Snake, eastern indigo | Drymarchon corais couperi | - | 4 | T |
| Snake, Florida pine | Pituophis melanoleucus mugitus | - | 4 | SC |
| Snake, giant garter | Thamnophis gigas | - | 8 | T |
| snake, Glossy | arizona elegans | - | 2 | SC |
| Snake, gray-banded king | Lampropeltis mexicana alterna | - | 2 | RT |
| Snake, Gulf salt marsh | Nerodia clarkii | - | 4 | SC |
| Snake, Key ringneck | Diadophis punctatus acricus | - | 4 | SC |
| Snake, Kirtland's | Clonophis kirtlandii | - | 3 | SC |
| Snake, Lake Erie water | Nerodia sipedon insularum | Lake Erie offshore islands and their adjacent waters (located more than 1 mile from mainland)_U.S.A. (OH), Canada (Ont.) | 3 | T |
| Snake, Louisiana pine | Pituophis ruthveni | - | 4 | C |
| Snake, Maria Island | Liophus ornatus | - | Foreign | E |
| Snake, narrowhead garter | Thamnophis rufipunctatus | - | 2 | SC |
| Snake, northern pine | Pituophis melanoleucus melanoleucus | - | 4 | SC |
| snake, Northern water | Nerodia sipedon | Upper Tidal Potomac River population | 5 | RT |
| Snake, queen | Regina septemvittata | - | 4 | SC |
| Snake, Rimrock crowned | Tantilla oolitica | - | 4 | SC |
| snake, Ringneck | diadophis punctatus | - | 2 | SC |
| Snake, San Bernardino mountain king | Lampropeltis zonata parvirubra | - | 1 | SC |
| Snake, San Bernardino ringneck | Diadophis punctatus modestus | - | 1 | SC |
| Snake, San Diego Mountain king | Lampropeltis zonata pulchra | - | 1 | SC |
| Snake, San Diego ringneck | Diadophis punctatus similis | - | 1 | SC |
| Snake, San Francisco garter | Thamnophis sirtalis tetrataenia | - | 8 | E |
| Snake, Santa Cruz Island gopher | Pituophis melanoleucus pumilis | - | 1 | SC |
| Snake, short-headed garter | Thamnophis brachystoma | - | 5 | SC |
| Snake, short-tailed | Stilosoma extenuatum | - | 4 | SC |
| snake, Sonoran lyre | trimorphodon biscutatus ssp. lambda | - | 6 | SC |
| Snake, South coast garter | Thamnophis sirtalis ssp. | - | 1 | SC |
| Snake, southern hognose | Heterodon simus | - | 4 | SC |
| Snake, Texas garter | Thamnophis sirtalis annectens | - | 2 | SC |
| Snake, Tucson shovel-nosed | Chionactis occipitalis klauberi | - | 2 | C |
| snake, Tucson shovel-nosed | chionactis occiptalis ssp. klauberi | - | 2 | SC |
| Snake, two-striped garter | Thamnophis hammondii | - | 1 | SC |
| snake, Valley Form ground | sonora semiannulata | - | 2 | SC |
| snake, Western long-nosed | rhinocheilus lecontei ssp. lecontei | - | 6 | SC |
| snakehead, northern | Channa argus | - | Foreign | RT |
| Snakeroot | Eryngium cuneifolium | - | 4 | E |
| Snaketail, Alleghany | Ophiogomphus incurvatus alleghaniensis | - | 4 | SC |
| Snaketail, Edmund's | Ophiogomphus edmundo | - | 4 | SC |
| Snaketail, extra-striped | Ophiogomphus anomalus | - | 3 | SC |
| Snaketail, midget | Ophiogomphus howei | - | 4 | SC |
| Snaketail, Ozark | Ophiogomphus westfalli | - | 4 | SC |
| Snaketail, St. Croix | Ophiogomphus sp. | - | 3 | SC |
| Snakewood, Comal | Colubrina stricta | - | 2 | SC |
| Snapdragon, dimorphic | Antirrhinum subcordatum | - | 1 | RT |
| Snapdragon, island | Galvezia speciosa | - | 1 | SC |
| Snapdragon, oval-leaved | Antirrhinum ovatum | - | 1 | RT |
| Sneezeweed, Virginia | Helenium virginicum | - | 5 | T |
| Snowbell, Young's | Styrax youngae | - | 2 | SC |
| Snowbells, Texas | Styrax texanus | - | 2 | E |
| Snowberry, McKittrick | Symphoricarpos guadalupensis | - | 2 | SC |
| Soaproot, Red Hills | Chlorogalum grandiflorum | - | 1 | SC |
| Solenodon, Cuban | Solenodon cubanus | - | Foreign | E |
| Solenodon, Haitian | Solenodon paradoxus | - | Foreign | E |
| Sorrel, [unnamed] | Rumex krausei | - | 7 | SC |
| Spadefoot, western | Scaphiopus hammondii | - | 1 | SC |
| Spanishneedle, giant | Palafoxia arida gigantea | - | 1 | SC |
| Sparrow, Alameda song | Melospiza melodia pusillula | - | 1 | SC |
| Sparrow, Amak song | Melospiza melodia amaka | - | 7 | RT |
| Sparrow, Bachman's | Aimophila aestivalis | - | 4 | SC |
| Sparrow, Baird's | Ammodramus bairdii | - | 6 | RT |
| Sparrow, Belding's savannah | Passerculus sandwichensis beldingi | - | 1 | SC |
| Sparrow, Bell's sage | Amphispiza belli belli | - | 1 | SC |
| Sparrow, Cape Sable seaside | Ammodramus maritimus mirabilis | - | 4 | E |
| Sparrow, dusky seaside | Ammodramus maritimus nigrescens | - | 4 | D3A |
| Sparrow, Florida grasshopper | Ammodramus savannarum floridanus | - | 4 | E |
| Sparrow, Grasshopper | Ammodramus savannarum | - | 1 | SC |
| Sparrow, Grasshopper | Ammodramus savannarum ssp. perpallidus | - | 8 | SC |
| Sparrow, Henslow's | Ammodramus henslowii | - | 3 | RT |
| Sparrow, large-billed savannah | Passerculus sandwichensis rostratus | - | 1 | SC |
| Sparrow, Lincoln's | Melospiza lincolnii | - | 1 | SC |
| Sparrow, Oregon vesper | Pooecetes gramineus ssp. affinis | - | 1 | SC |
| Sparrow, San Clemente sage | Amphispiza belli clementeae | - | 8 | T |
| Sparrow, San Pablo song | Melospiza melodia samuelis | - | 1 | SC |
| Sparrow, Santa Barbara song | Melospiza melodia graminea | - | 8 | D3A |
| Sparrow, Smyrna seaside | Ammodramus maritima pelonota | - | 4 | RT |
| Sparrow, Southern California rufous-crowned | Aimophila ruficeps canescens | - | 1 | SC |
| Sparrow, Suisun song | Melospiza melodia maxillaris | - | 1 | SC |
| Sparrow, Texas Botteri's | Aimophila botterii texana | - | 2 | SC |
| Sparrow, Texas Henslow's | Ammodramus henslowii houstonensis | - | 2 | RT |
| Sparrow, Texas olive | Arremonops rufivirgatus rufivirgatus | - | 2 | SC |
| Sparrow, Wakulla seaside | Ammodramus maritima junicola | - | 4 | RT |
| Sparrow, Yuma rufous-crowned | Aimophila ruficeps rupicola | - | 2 | RT |
| Sparrowhawk, Anjouan Island | Accipiter francesii pusillus | - | Foreign | E |
| Spearscale, valley | Atriplex joaquiniana | - | 1 | SC |
| Spectacle-pod, beach | Dithyrea maritima | - | 1 | SC |
| Spectaclecase (mussel) | Cumberlandia monodonta | - | 3 | C |
| Speedwell, Copeland's | Veronica copelandii | - | 1 | RT |
| Sphecid wasp, bidecoratus | Ectemnius bidecoratus | - | 1 | SC |
| Sphecid wasp, brown cross ectemnius | Ectemnius fulvicrus | - | 1 | SC |
| Sphecid wasp, Giffard's ectemnius | Ectemnius giffardi | - | 1 | SC |
| Sphecid wasp, Haleakala ectemnius | Ectemnius haleakalae | - | 1 | SC |
| Sphecid wasp, Hawaiian deinomimesan | Deinomimesa hawaiiensis | - | 1 | SC |
| Sphecid wasp, puna deinomimesan | Deinomimesa punae | - | 1 | SC |
| Sphecid wasp, redheaded | Eucerceris ruficeps | - | 1 | SC |
| Sphecid wasp, redtail | Ectemnius rubrocaudatus | - | 1 | SC |
| Sphecid wasp, short-foot ectemnius | Ectemnius curtipes | - | 1 | SC |
| Sphinx moth, Blanchards' | Adhemarius blanchardorum | - | 2 | SC |
| Sphinx moth, Weist's | Euproserpinus wiesti | - | 6 | RT |
| Spider, Bandit Cave | Cicurina bandida | - | 2 | SC |
| Spider, Cave Spring Cave | Nesticus jonesi | - | 4 | SC |
| Spider, cavern sheet-web | Islandiana speophila | - | 5 | SC |
| Spider, Crystal Caverns cave | Nesticus furtivus | - | 4 | SC |
| Spider, Dolloff Cave | Meta dollof | - | 1 | UR |
| Spider, Government Canyon Bat Cave | Neoleptoneta microps | - | 2 | E |
| Spider, Grassy Creek Cave | Nesticus dilutus | - | 4 | SC |
| Spider, Hawaiian | Doryonychus raptor | - | NA | RT |
| Spider, Kauai cave wolf or pe'e pe'e maka 'ole | Adelocosa anops | - | 1 | E |
| Spider, Key gnaphosid | Cesonia irvingi | - | 4 | SC |
| Spider, Lost Nantahala Cave | Nesticus cooperi | - | 4 | SC |
| Spider, Rosemary wolf | Lycosa ericeticola | - | 4 | RT |
| Spider, Santa Cruz telemid | Telema sp. | - | 1 | SC |
| Spider, spruce-fir moss | Microhexura montivaga | - | 4 | E |
| Spider, Tooth Cave | Leptoneta myopica | - | 2 | E |
| Spider, Torreya trap-door | Cyclocosmia torreya | - | 4 | SC |
| Spider, Ubick's gnaphoid | Talanites ubicki | - | NA | RT |
| Spider, Valentine's cave | Nesticus valentinei | - | 4 | SC |
| Spider, [unnamed] | Cicurina cueva | - | 2 | UR |
| Spider-lily, shoals | Hymenocallis coronaria | - | 4 | SC |
| Spider-lily, [unnamed] | Hymenocallis henryae | - | 4 | SC |
| Spiderflower, slender | Cleome multicaulis | - | 6 | SC |
| Spiderflower, wild (unnamed ssp.) | Cleome spinosa ssp. | - | 1 | RT |
| Spiderlily, Godfrey's | Hymenocallis godfreyi | - | 4 | SC |
| Spiderling, Mathis | Boerhavia mathisiana | - | 2 | SC |
| Spiderwort, Wright's | Tradescantia wrightii | - | 2 | RT |
| Spike, Cape Fear | Elliptio marsupiobesa | - | 4 | RT |
| Spike, false | Quincuncina mitchelli | - | 2 | UR |
| Spike, purple, Texas | Hexalectris warnockii | - | 2 | SC |
| Spike, Waccamaw | Elliptio waccamawensis | - | 4 | SC |
| spike-moss, Ashy | selaginella cinerascens | - | 6 | SC |
| Spikedace | Meda fulgida | - | 2 | T |
| Spikerush, cylinder | Eleocharis cylindrica | - | 2 | SC |
| Spikerush, short-fruited | Eleocharis brachycarpa | - | 2 | SC |
| Spiketail, Say's | Cordulegaster sayi | - | 4 | RT |
| Spikeweed, pappose | Hemizonia parryi congdonii | - | 1 | SC |
| Spinedace, Big Spring | Lepidomeda mollispinis pratensis | - | 8 | T |
| Spinedace, Little Colorado | Lepidomeda vittata | - | 2 | T |
| Spinedace, Pahranagat | Lepidomeda altivelis | - | 1 | RT |
| Spinedace, Virgin River | Lepidomeda mollispinis mollispinis | - | 6 | RT |
| Spinedace, White River | Lepidomeda albivallis | - | 8 | E |
| Spineflower, Ben Lomond | Chorizanthe pungens var. hartwegiana | - | 8 | E |
| Spineflower, Blakley's | Chorizanthe blakleyi | - | 1 | RT |
| Spineflower, Brewer's | Chorizanthe breweri | - | 1 | RT |
| Spineflower, Howell's | Chorizanthe howellii | - | 8 | E |
| Spineflower, Indian Valley | Aristocapsa insignis | - | 1 | RT |
| Spineflower, Mojave | Chorizanthe spinosa | - | 1 | RT |
| Spineflower, Monterey | Chorizanthe pungens var. pungens | - | 8 | T |
| Spineflower, one-awned | Chorizanthe rectispina | - | 1 | SC |
| Spineflower, Orcutt's | Chorizanthe orcuttiana | - | 8 | E |
| Spineflower, Parry's | Chorizanthe parryi parryi | - | 1 | SC |
| spineflower, Prostrate | chorizanthe procumbens | - | 6 | SC |
| spineflower, Ramona | Chorizanthe leptotheca | - | 1 | SC |
| Spineflower, Robust (incl. Scotts Valley) | Chorizanthe robusta (incl. vars. robusta and hartwegii) | - | 8 | E |
| Spineflower, San Benito | Chorizanthe biloba immemora | - | 1 | SC |
| Spineflower, San Fernando Valley | Chorizanthe parryi var. fernandina | - | 8 | C |
| Spineflower, San Francisco Bay | Chorizanthe cuspidata cuspidata | - | 1 | SC |
| Spineflower, slender-horned | Dodecahema leptoceras | - | 8 | E |
| Spineflower, Sonoma | Chorizanthe valida | - | 8 | E |
| Spinymussel, Altamaha | Elliptio spinosa | - | 4 | C |
| Spinymussel, James | Pleurobema collina | - | 5 | E |
| Spinymussel, Tar River | Elliptio steinstansana | - | 4 | E |
| Spiraea, Virginia | Spiraea virginiana | - | 5 | T |
| Spleenwort, Scott's | Asplenium ebenoides | - | 4 | RT |
| Spleenwort, [unnamed] | Asplenium andrewsii | - | 2 | RT |
| Spleenwort, [unnamed] | Asplenium heteroresiliens | - | 4 | SC |
| Spleenwort, [unnamed] | Asplenium kentuckiense | - | 4 | RT |
| Spleenwort, [unnamed] | Asplenium leucostegioides | - | 1 | RT |
| Spleenwort, [unnamed] | Asplenium plenum | - | 4 | SC |
| Splittail, Clear Lake | Pogonichthys ciscoides | - | 1 | RT |
| Splittail, Sacramento | Pogonichthys macrolepidotus | - | 8 | UR |
| Sponge, Carolina | Corvomeyenia carolinensis | - | 4 | SC |
| Sponge, Kissimmee | Ephydatia subtilis | - | 4 | SC |
| Sponge, muscular | Anheteromyia biceps | - | 3 | RT |
| Sponge, Oklawaha | Dosilia palmeri | - | 4 | SC |
| Sponge, Oneida | Spongilla heteroslerifa | - | 5 | RT |
| Sponge, Pennsylvania | Heteromeyenia longistylis | - | 5 | RT |
| Sponge, spongy | Spongilla sponginosa | - | 4 | RT |
| Spring beauty, Peirson's | Claytonia lanceolata peirsonii | - | 1 | SC |
| Spring-beauty, [unnamed] | Claytonia virginica hammondiae | - | 5 | SC |
| Springfish, Hiko White River | Crenichthys baileyi grandis | - | 8 | E |
| Springfish, Moapa White River | Crenichthys baileyi moapae | - | 1 | UR |
| Springfish, Moorman White River | Crenichthys baileyi thermophilus | - | 1 | SC |
| Springfish, Preston White River | Crenichthys baileyi albivallis | - | 1 | UR |
| Springfish, Railroad Valley | Crenichthys nevadae | - | 8 | T |
| Springfish, White River | Crenichthys baileyi baileyi | - | 8 | E |
| Springsnail (=Tryonia), Phantom | Tryonia cheatumi | - | 2 | C |
| Springsnail, Aardhals | Pyrgulopsis aardhali | - | 1 | SC |
| Springsnail, Alamosa | Tryonia alamosae | - | 2 | E |
| Springsnail, brown | Pyrgulopsis solus | - | 2 | SC |
| Springsnail, Bruneau Hot | Pyrgulopsis bruneauensis | - | 1 | E |
| Springsnail, Bylas | Pyrgulopsis arizonae | - | 2 | SC |
| Springsnail, Chupadera | Pyrgulopsis chupaderae | - | 2 | C |
| Springsnail, Columbia | Pyrgulopsis | - | 1 | RT |
| Springsnail, Crystal | Pyrgulopsis crystalis | - | 8 | UR |
| Springsnail, Davis County | Fontelicella davisi | - | 2 | SC |
| Springsnail, distal-gland | Pyrgulopsis nanus | - | 8 | UR |
| Springsnail, elongate mud meadows | Pyrgulopsis notidicola | - | 8 | C |
| Springsnail, elongate-gland | Pyrgulopsis isolatus | - | 8 | UR |
| Springsnail, Fairbanks | Pyrgulopsis fairbanksensis | - | 8 | UR |
| Springsnail, Fish Slough | Pyrgulopsis perturbata | - | 1 | SC |
| Springsnail, fossil | Pyrgulopsis simplex | - | 2 | SC |
| Springsnail, Gila | Pyrgulopsis gilae | - | 2 | C |
| Springsnail, Gonzales | Tryonia circumstriata(=stocktonensis) | - | 2 | C |
| Springsnail, Grand Wash | Pyrgulopsis bacchus | - | 2 | SC |
| Springsnail, Harney Lake | Pyrgulopsis hendersoni | - | 1 | RT |
| Springsnail, Huachuca | Pyrgulopsis thompsoni | - | 2 | C |
| Springsnail, Idaho | Pyrgulopsis idahoensis | - | 1 | DO |
| Springsnail, Jackson Lake | Pyrgulopsis robusta | - | 6 | RT |
| Springsnail, Kingman | Pyrgulopsis conicus | - | 2 | SC |
| Springsnail, Koster's | Juturnia kosteri | - | 2 | E |
| Springsnail, median-gland Nevada | Pyrgulopsis pisteri | - | 8 | UR |
| Springsnail, Montezuma Well | Pyrgulopsis montezumensis | - | 2 | SC |
| Springsnail, New Mexico | Pyrgulopsis thermalis | - | 2 | C |
| Springsnail, Oasis Valley | Pyrgulopsis micrococcus | - | 1 | UR |
| Springsnail, Owens | Pyrgulopsis owensensis | - | 1 | SC |
| Springsnail, Page | Pyrgulopsis morrisoni | - | 2 | C |
| Springsnail, Pecos | Fontelicella pecosensis | - | 2 | SC |
| Springsnail, Presidio County | Fontelicella metcalfi | - | 2 | SC |
| Springsnail, Roswell | Pyrgulopsis roswellensis | - | 2 | E |
| Springsnail, San Bernadino | Pyrgulopsis bernardina | - | 2 | C |
| Springsnail, Socorro | Pyrgulopsis neomexicana | - | 2 | E |
| Springsnail, Three Forks | Pyrgulopsis trivialis | - | 2 | C |
| Springsnail, Verde Rim | Pyrgulopsis glandulosus | - | 2 | SC |
| Springsnail, Wongs | Pyrgulopsis wongi | - | 1 | SC |
| Springtail, Gandy Creek cave | Pseudosinella certa | - | 5 | SC |
| Springtail, shelled cave | Pseudosinella testa | - | 5 | SC |
| spurge, Cliff | euphorbia misera | - | 8 | SC |
| Spurge, Darlington's | Euphorbia purpurea | - | 5 | SC |
| Spurge, deltoid | Chamaesyce deltoidea ssp. deltoidea | - | 4 | E |
| Spurge, flat-seeded | Chamaesyce platysperma | - | 1 | SC |
| Spurge, Garber's | Chamaesyce garberi | - | 4 | T |
| Spurge, Hoover's | Chamaesyce hooveri | - | 8 | T |
| Spurge, Paria | Euphorbia nephradenia | - | 6 | RT |
| Spurge, perennial | Chamaesyce perennans | - | 2 | RT |
| Spurge, Porter's, | Chamaesyce porteriana scoparia | - | 4 | SC |
| Spurge, Porter's, Key | Chamaesyce porteriana keyensis | - | 4 | SC |
| Spurge, Rosy-pink | Euphorbia rosescens | - | 4 | SU |
| Spurge, swallow | Chamaesyce golondrina | - | 2 | SC |
| Spurge, telephus | Euphorbia telephioides | - | 4 | T |
| Spurge, three-tongued | Chamaesyce chaetocalyx triligulata | - | 2 | SC |
| Spurge, wedge | Chamaesyce deltoidea serpyllum | - | 4 | C |
| Squaw carpet | Ceanothus prostratus laxus | - | 1 | RT |
| Squirrel, Allen's 13-lined ground | Spermophilus tridecemlineatus alleni | - | 6 | SC |
| Squirrel, Carolina northern flying | Glaucomys sabrinus coloratus | - | 4 | E |
| Squirrel, Chiricahua Nayarit | Sciurus nayaritensis chiricahuae | - | 2 | SC |
| Squirrel, Delmarva Peninsula fox | Sciurus niger cinereus | Entire, except Sussex Co., DE | 5 | E |
| Squirrel, Delmarva Peninsula fox | Sciurus niger cinereus | U.S.A. (DE, Sussex Co.) | 5 | EXPN |
| Squirrel, mangrove fox (=Big Cypress fox) | Sciurus niger avicennia | - | 4 | RT |
| Squirrel, Mohave ground | Xerospermophilus mohavensis | - | 8 | UR |
| Squirrel, Mount Graham red | Tamiasciurus hudsonicus grahamensis | - | 2 | E |
| Squirrel, Nelson's antelope ground | Ammospermophilus nelsoni | - | 1 | SC |
| Squirrel, northern Idaho ground | Spermophilus brunneus brunneus | - | 1 | T |
| Squirrel, Palm Springs round-tailed ground (=Coachella Valley) | Xerospermophilus tereticaudus chlorus | - | 8 | C |
| Squirrel, Prince of Wales flying | Glaucomys sabrinus griseifrons | - | 7 | RT |
| Squirrel, San Bernardino northern flying | Glaucomys sabrinus californicus | - | 1 | SC |
| Squirrel, Santa Catalina Mountains | Sciurus arizonensis catalinae | - | 2 | SC |
| Squirrel, Sherman's fox | Sciurus niger shermani | - | 4 | SC |
| Squirrel, Southern Idaho ground | Spermophilus brunneus endemicus | - | 1 | C |
| Squirrel, Virginia northern flying | Glaucomys sabrinus fuscus | - | 5 | DM |
| Squirrel, Washington ground | Urocitellus washingtoni | - | 1 | C |
| Squirrel, western grey | Sciurus griseus | - | 1 | RT |
| St. John's Wort, Radford's | Hypericum sp. 1 | - | 4 | RT |
| Stag beetle, Kauai flightless | Apterocyclus honoluluensis | - | 1 | SC |
| Stag, Barbary | Cervus elaphus barbarus | - | Foreign | E |
| Stag, Kashmir | Cervus elaphus hanglu | - | Foreign | E |
| Star leaf, Arizona | Choisya arizonica | - | 2 | RT |
| Star leaf, Santa Cruz | Choisya mollis | - | 2 | SC |
| Star-grass, [unnamed] | Hypoxis longii | - | 4 | RT |
| Star-tulip, long-haired | Calochortus longebarbatus longebarbatus | - | 1 | SC |
| Starling, Micronesian | Aplonisopaca guami | - | NA | SU |
| Starling, Ponape mountain | Aplonis pelzelni | - | Foreign | E |
| Starling, Rothschild's (myna) | Leucopsar rothschildi | - | Foreign | E |
| Steelhead | Oncorhynchus (=Salmo) mykiss | All naturally spawned populations (and their progeny) in streams and tributaries to the Columbia R. between the Cowlitz and Wind Rivers, WA, inclusive, and the Willamette and Hood Rivers, OR, inclusive, excluding the Upper Willamette River Basin above Willamette Falls and excluding the Little and Big White Salmon Rivers in WA | NMFS | T |
| Steelhead | Oncorhynchus (=Salmo) mykiss | All naturally spawned populations (and their progeny) in the Upper Columbia R. Basin upstream from the Yakima R., WA, to the U.S./Canada border, and also including the Wells Hatchery stock | NMFS | T |
| Steelhead | Oncorhynchus (=Salmo) mykiss | U.S.A. (OR) All naturally spawned winter-run populations in the Willamette R. and its tributaries from Willamette Falls to the Calapooia R., inclusive | NMFS | T |
| Steelhead | Oncorhynchus (=Salmo) mykiss | All naturally spawned populations (and their progeny) in the Sacramento and San Joaquin Rivers and their tributaries, excluding San Francisco and San Pablo Bays and their tributaries | NMFS | T |
| Steelhead | Oncorhynchus (=Salmo) mykiss | All naturally spawned populations (and their progeny) in streams from the Pajaro R. (inclusive) located in Santa Cruz County, CA, to (but not including) the Santa Maria R | NMFS | T |
| Steelhead | Oncorhynchus (=Salmo) mykiss | All naturally spawned populations (and their progeny) in rivers from the Santa Maria R., San Luis Obispo County, CA (inclusive) to Malibu Cr., Los Angeles County, CA (inclusive) | NMFS | E |
| Steelhead | Oncorhynchus (=Salmo) mykiss | Klamath Mountains Province steelhead(Oncorhynchus mykiss).Includes all Naturally spawned populations of Steelhead (and their progeny) in coastal river basins ranging from the Elk River in Curry County, Oregon, to the Klamath River, inclusive, in Del Norte County, California | NMFS | UR |
| Steelhead | Oncorhynchus (=Salmo) mykiss | All naturally spawned populations (and their progeny) in streams in the Snake R. Basin of southeast WA, northeast OR, and ID | NMFS | T |
| Steelhead | Oncorhynchus (=Salmo) mykiss | All naturally spawned populations (and their progeny) in streams from the Russian R. to Aptos Cr., Santa Cruz County, CA (inclusive), and the drainages of San Francisco and San Pablo Bays eastward to the Napa R. (inclusive), Napa County, CA, excluding the Sacramento-San Joaquin R. Basin of the Central Valley of CA | NMFS | T |
| Steelhead | Oncorhynchus (=Salmo) mykiss | U.S.A. (OR, WA) All naturally spawned populations in streams above and excluding the Wind R. in Washington, and the Hood R. in Oregon, upstream to, and including, the Yakima R. Excluded are steelhead from the Snake R. Basin | NMFS | T |
| Steelhead | Oncorhynchus (=Salmo) mykiss | All naturally spawned populations and their progeny in river basins from Redwood Creek in Humboldt County, CA to the Gualala River in Mendocino County, CA (inclusive) | NMFS | T |
| Stick-pea, two-flowered | Calliandra biflora | - | 2 | RT |
| Stickleaf, hairy | Mentzelia hirsutissima stenophylla | - | 1 | RT |
| Stickleaf, Mesa Verde | Hackelia gracilenta | - | 6 | SC |
| Stickleaf, Packard's | Mentzelia packardiae | - | 1 | UR |
| Stickleaf, Royal Gorge | Mentzelia densa | - | 6 | RT |
| Stickleaf, smooth | Mentzelia mollis | - | 1 | UR |
| Stickleaf, [unnamed] | Mentzelia nitens leptocaulis | - | 2 | RT |
| Stickleback, Santa Ana threespine | Gasterosteus aculeatus santaannae | - | 1 | RT |
| Stickleback, unarmored threespine | Gasterosteus aculeatus williamsoni | - | 8 | E |
| Stickseed, Cronquist's | Hackelia cronquistii | - | 1 | SC |
| Stickseed, Davis' | Hackelia davisii | - | 1 | RT |
| Stickseed, Poison Canyon | Hackelia brevicula | - | 1 | SC |
| Stickseed, Sharsmth's | Hackelia sharsmithii | - | 1 | RT |
| Stickseed, showy | Hackelia venusta | - | 1 | E |
| Stickseed, [unnamed] | Hackelia ibapensis | - | 6 | SC |
| Stickseed, [unnamed] | Hackelia ophiobia | - | 1 | RT |
| Stickyseed, Point Reyes | Blennosperma nanum robustum | - | 1 | SC |
| Stilt, black | Himantopus novaezelandiae | - | Foreign | E |
| Stilt, Hawaiian | Himantopus mexicanus knudseni | - | 1 | E |
| Stingingbush | Malpighia infestissima | - | 4 | SC |
| Stink bells | Fritillaria agrestis | - | 1 | RT |
| Stink bug, gray oechalia | Oechalia grisea | - | 1 | SC |
| Stink bug, patruelis oechalia | Oechalia patruelis | - | 1 | SC |
| Stirrupshell | Quadrula stapes | - | 4 | E |
| Stitchwort, water | Arenaria fontinalis | - | 4 | SC |
| Stolon, [unnamed] | Draba sphaerocarpa | - | 1 | RT |
| Stonecrop, Applegate | Sedum oblanceolatum | - | 1 | SC |
| Stonecrop, Canyon Creek | Sedum paradisum | - | 1 | SC |
| Stonecrop, Davidson's | Sedum niveum | - | 1 | RT |
| Stonecrop, Feather River | Sedum albomarginatum | - | 1 | RT |
| Stonecrop, Heckner's | Sedum laxum heckneri | - | 1 | RT |
| Stonecrop, Lake County | Parvisedum leiocarpum | - | 8 | E |
| Stonecrop, Nevius' | Sedum nevii | - | 4 | SC |
| Stonecrop, pale yellow | Sedum laxum flavidum | - | 1 | RT |
| Stonecrop, Pine City | Sedum pinetorum | - | 1 | SC |
| Stonecrop, Red Mountain | Sedum eastwoodiae | - | 8 | C |
| Stonecrop, Reid's | Sedum moranii | - | 1 | SC |
| Stonecrop, Robert's | Sedum robertsianum | - | 2 | SC |
| Stonecrop, star-fruited, small | Sedum radiatum depauperatum | - | 1 | SC |
| Stonecrop, Texas | Sedum texanum | - | 2 | RT |
| Stonecrop, [unnamed] | Sedum pusillum | - | 4 | RT |
| Stonecrop, [unnamed] | Sedum rosea roanensis | - | 4 | RT |
| Stonefly, Cheaha beloneurian | Beloneuria jamesae | - | 4 | SC |
| Stonefly, Chukcho | Haploperla chukcho | - | 4 | SC |
| Stonefly, Fender's soliperlan | Soliperla fenderi | - | 1 | SC |
| Stonefly, Georgia beloneurian | Beloneuria georgiana | - | 4 | RT |
| Stonefly, Hanson's appalachian | Hansonoperla appalachia | - | 5 | RT |
| Stonefly, Lake Tahoe benthic | Capnia lacustra | - | 1 | SC |
| Stonefly, Leon River winter | Taeniopteryx starki | - | 2 | SC |
| Stonefly, meltwater lednian | Lednia tumana | - | 6 | UR |
| Stonefly, Natchez | Alloperla natchez | - | 4 | SC |
| Stonefly, Robert's alloperlan | Alloperla roberti | - | 3 | RT |
| Stonefly, Schoolhouse Springs leuctran | Leuctra szczytkoi | - | 4 | RT |
| Stonefly, Shirttail Creek | Megaleuctra sierra | - | 1 | SC |
| Stonefly, Wahkeena Falls flightless | Zapada wahkeena | - | 1 | SC |
| Stoneroller, Mexican | Campostoma ornatum | - | 2 | SC |
| Stopper, Simpson | Myrcianthes fragrans simpsonii | - | 4 | SC |
| Stork, oriental white | Ciconia boyciana (=ciconia b.) | - | Foreign | E |
| Stork, wood | Mycteria americana | U.S.A. (AL, FL, GA, SC) | 4 | E |
| Storm-petrel, ashy | Oceanodroma homochroa | - | 1 | RT |
| Storm-petrel, band-rumped | Oceanodroma castro | Hawaii DPS | 1 | C |
| Streptanthus, alpine | Streptanthus gracilis | - | 1 | RT |
| Streptanthus, Contact Mine | Streptanthus brachiatus brachiatus | - | 1 | SC |
| Stroganowia, Tiehm's | Stroganowia tiehmii | - | 1 | SC |
| Sturgeon, Alabama | Scaphirhynchus suttkusi | - | 4 | E |
| Sturgeon, Atlantic | Acipenser oxyrinchus oxyrinchus | - | NMFS | RT |
| Sturgeon, Beluga | Huso huso | - | Foreign | T |
| Sturgeon, gulf | Acipenser oxyrinchus desotoi | - | 4 | T |
| Sturgeon, lake | Acipenser fulvescens | - | 3 | SC |
| Sturgeon, North American green | Acipenser medirostris | U.S.A. (CA) Southern Distinct Population Segment | NMFS | T |
| Sturgeon, pallid | Scaphirhynchus albus | - | 6 | E |
| Sturgeon, shortnose | Acipenser brevirostrum | - | NMFS | E |
| Sturgeon, Shovelnose | Scaphirhynchus platorynchus | - | 6 | PSAT |
| Sturgeon, white | Acipenser transmontanus | U.S.A. (ID, MT), Canada (B.C.), (Kootenai R. system) | 1 | E |
| Succineid, Iowa Pleistocene | Succinea sp. | IA | 3 | SC |
| Succineid, Minnesota Pleistocene | Succinea sp. | MN | 3 | SC |
| sucker longnose | Catostomus catostomus | - | 5 | SU |
| Sucker, blue | Cycleptus elongatus | - | 3 | SC |
| Sucker, desert | Catostomus clarki ssp. | Desert | 1 | SC |
| Sucker, flannelmouth | Catostomus latipinnis | - | 2 | SC |
| Sucker, Goose Lake | Catostomus occidentalis lacusanserinus | - | 1 | SC |
| Sucker, harelip | Lagochila lacera | - | 4 | RT |
| Sucker, Jenny Creek | Catostomus rimiculus ssp. | - | 1 | SC |
| Sucker, June | Chasmistes liorus | - | 6 | E |
| Sucker, Klamath largescale | Catostomus snyderi | - | 1 | SC |
| Sucker, Lost River | Deltistes luxatus | - | 8 | E |
| Sucker, Meadow Valley Wash desert | Catostomus clarki ssp. | Meadow Valley | 1 | UR |
| Sucker, Modoc | Catostomus microps | - | 8 | E |
| Sucker, razorback | Xyrauchen texanus | entire | 6 | E |
| Sucker, rustyside | Moxostoma hamiltoni | - | 5 | RT |
| Sucker, Santa Ana | Catostomus santaanae | Los Angeles River basin, San Gabriel River basin, Santa Ana River basin | 8 | T |
| Sucker, shortnose | Chasmistes brevirostris | - | 8 | E |
| Sucker, Snake River | Chasmistes muriei | - | 6 | RT |
| Sucker, Sonora | Catostomus insignis | - | 2 | SC |
| Sucker, Wall Canyon | Catostomus sp. | - | 1 | UR |
| Sucker, Warner | Catostomus warnerensis | - | 1 | T |
| Sucker, Webug | Catostomus fecundus | - | 6 | RT |
| Sucker, White River desert | Catostomus clarki intermedius | - | 1 | UR |
| sucker, Yaqui | catostomus bernardini | - | 2 | SC |
| Sucker, Zuni bluehead | Catostomus discobolus yarrowi | - | 2 | C |
| Sugarspoon | Epioblasma arcaeformis | - | 4 | RT |
| Sullivantia, [unnamed] | Sullivantia sullivantii | - | 4 | RT |
| Sumac, Kearney's | Rhus kearneyi | - | 2 | RT |
| Sumac, Michaux's | Rhus michauxii | - | 4 | E |
| Sumac, [unnamed] | Rhus trilobata arenaria | - | 3 | SC |
| Summer-holly | Comarostaphylis diversifolia diversifolia | - | 1 | SC |
| Sunbird, Marungu | Nectarinia prigoginei | - | Foreign | E |
| Sunburst, Hartweg's golden | Pseudobahia bahiifolia | - | 8 | E |
| Sunburst, San Joaquin adobe | Pseudobahia peirsonii | - | 8 | T |
| Sunfish, bluebarred pygmy | Elassoma okatie | - | 4 | RT |
| Sunfish, Carolina pygmy | Elassoma boehlkei | - | 4 | SC |
| Sunfish, spring pygmy | Elassoma alabamae | - | 4 | SC |
| Sunflower, Algodones Dunes | Helianthus niveus tephrodes | - | 1 | SC |
| Sunflower, Dimmit | Helianthus praecox hirtus | - | 2 | SC |
| Sunflower, Eggert's | Helianthus eggertii | - | 4 | DM |
| Sunflower, Gulf beach | Helianthus debilis vestitus | - | 4 | SC |
| Sunflower, Laguna Mountains | Hulsea californica | - | 1 | RT |
| Sunflower, Los Angeles | Helianthus nuttallii parishii | - | 1 | SC |
| Sunflower, Paria | Viguiera soliceps | - | 6 | RT |
| Sunflower, Pecos (=puzzle, =paradox) | Helianthus paradoxus | - | 2 | T |
| Sunflower, San Mateo woolly | Eriophyllum latilobum | - | 8 | E |
| Sunflower, Schweinitz's | Helianthus schweinitzii | - | 4 | E |
| Sunflower, serpentine | Helianthus exilis | - | 1 | RT |
| Sunflower, whorled | Helianthus verticillatus | - | 4 | C |
| Suni, Zanzibar | Neotragus moschatus moschatus | - | Foreign | E |
| Sunnybell, Texas | Schoenolirion wrightii | - | 2 | RT |
| Sunray, Ash Meadows | Enceliopsis nudicaulis var. corrugata | - | 8 | T |
| Sunshine, Sonoma | Blennosperma bakeri | - | 8 | E |
| Supercoil, fragile | Glyphyalinia clingmani | - | 4 | SC |
| Supercoil, Roan | Paravitrea varidens | - | 4 | SC |
| Supercoil, sculpted | Paravitrea ternaria | - | 4 | SC |
| Supercoil, sidelong | Paravitrea ceres | - | 5 | SC |
| swallow, Bank | riparia riparia | - | 7 | SC |
| swallow, Tree | tachycineta bicolor | - | 7 | SC |
| Swan, trumpeter | Cygnus buccinator | Entire | 6 | SC |
| Swan, trumpeter | Cygnus buccinator | Rocky Mountain Population | 6 | SU |
| Swan, trumpeter | Cygnus buccinator | Greater Yellowstone (Tri-state) breeding pop (DPS) | 6 | UR |
| Sweet-bay, Sierra | Myrica hartwegii | - | 1 | RT |
| Sweet-cicely, Livermore | Osmorhiza mexicana bipatriata | - | 2 | SC |
| Swift, Black | Cypseloides niger | - | 1 | SC |
| swift, Vaux's | chaetura vauxi | - | 6 | SC |
| Swiftlet, Mariana gray | Aerodramus vanikorensis bartschi | - | 1 | E |
| Swordfern, Dudley's | Polystichum dudleyi | - | 1 | RT |
| Swordfern, Kruckeberg's | Polystichum kruckebergii | - | 1 | RT |
| Synandra, [unnamed] | Synandra hispidula | - | 4 | RT |
| Tabanid fly, brown merycomyian | Merycomyia brunnea | - | 4 | SC |
| Tabanid fly, Florida asaphomyian | Asaphomyia floridensis | - | 4 | SC |
| Tabanid fly, Ross's apatalestes | Apatalestes rossi | - | 1 | RT |
| Tabanid fly, Texas asaphomyian | Asaphomyia texanus | - | 2 | SC |
| Tabanid fly, volutine stonemyian | Stonemyia volutina | - | 1 | RT |
| Tadpole shrimp, vernal pool | Lepidurus packardi | - | 8 | E |
| Tahr, Arabian | Hemitragus jayakari | - | Foreign | E |
| taildropper, Blue-gray | prophysaon coeruleum | - | 6 | SC |
| taildropper, Papillose | prophysaon dubium | - | 6 | SC |
| Takahe | Porphyrio mantelli | - | Foreign | UR |
| Talussnail, Clark Peak | Sonorella christenseni | - | 2 | SC |
| Talussnail, Dona Ana | Sonorella todseni | - | 2 | SC |
| Talussnail, Franklin Mountain | Sonorella metcalfi | - | 2 | SC |
| Talussnail, Ladybug Saddle | Sonorella sp. | - | 2 | SC |
| Talussnail, mimic | Sonorella imitator | - | 2 | RT |
| Talussnail, Pinaleno | Sonorella grahamensis | - | 2 | SC |
| Talussnail, San Xavier | Sonorella eremita | - | 2 | RT |
| Talussnail, Squaw Park | Sonorella allynsmithi | - | 2 | SC |
| Talussnail, Wet Canyon | Sonorella macrophallus | - | 2 | RT |
| Tamaraw | Bubalus mindorensis | - | Foreign | E |
| Tamarin, golden-rumped | Leontopithecus spp. | - | Foreign | E |
| Tamarin, pied | Saguinus bicolor | - | Foreign | E |
| Tamarin, white-footed | Saguinus leucopus | - | Foreign | T |
| Tamarindillo, [unnamed] | Cassia exunguis | - | 4 | RT |
| Tanager, black-backed | Tangara peruviana | - | Foreign | UR |
| Tanager, cherry-throated | Nemosia rourei | - | Foreign | PE |
| tanager, Summer | piranga rubra | - | 6 | SC |
| Tango, Miyako (=Toyko bitterling) | Tanakia tanago | - | Foreign | E |
| Tansy, dune | Tanacetum camphoratum | - | 1 | RT |
| Tansy, Zion | Sphaeromeria ruthiae | - | 6 | SC |
| Tansy, [unnamed] | Sphaeromeria compacta | - | 1 | SC |
| Tapaculo, Brasilia | Scytalopus novacapitalis | - | Foreign | UR |
| Tapir, Asian | Tapirus indicus | - | Foreign | E |
| Tapir, Central American | Tapirus bairdii | - | Foreign | E |
| Tapir, mountain | Tapirus pinchaque | - | Foreign | E |
| Tapir, South American (=Brazilian) | Tapirus terrestris | - | Foreign | E |
| Taraxacum, California | Taraxacum californicum | - | 8 | E |
| Tarplant, Gaviota | Deinandra increscens ssp. villosa | - | 8 | E |
| Tarplant, Otay | Deinandra (=Hemizonia) conjugens | - | 8 | T |
| Tarplant, Santa Cruz | Holocarpha macradenia | - | 8 | T |
| Tarplant, smooth | Hemizonia pungens laevis | - | 1 | SC |
| Tarplant, southern | Hemizonia parryi australis | - | 1 | SC |
| Tarsier, Philippine | Tarsius syrichta | - | Foreign | T |
| Tartaruga | Podocnemis expansa | - | Foreign | E |
| Tarweed, Hall's | Hemizonia halliana | - | 1 | RT |
| Tarweed, Mojave | Hemizonia mohavensis | - | 1 | SC |
| Tarweed, Red Rock | Hemizonia arida | - | 1 | SC |
| Tarweed, Santa Susana | Hemizonia minthornii | - | 1 | SC |
| Tarweed, seaside | Hemizonia multicaulis multicaulis | - | 1 | SC |
| Tarweed, Tecate | Hemizonia floribunda | - | 1 | SC |
| Tarweed, Tiburon | Hemizonia multicaulis vernalis | - | 1 | SC |
| Tauschia, glaucous | Tauschia glauca | - | 1 | RT |
| Tauschia, Hoover's | Tauschia hooveri | - | 1 | SC |
| Tauschia, Howell's | Tauschia howellii | - | 1 | SC |
| Teal, Campbell Island flightless | Anas aucklandica nesiotis | - | Foreign | E |
| Temoleh, Ikan (minnow) | Probarbus jullieni | - | Foreign | E |
| Terciopelo | Abutilon commutatum | - | 4 | RT |
| Tern, black | Chlidonias niger | - | 6 | SC |
| Tern, California least | Sterna antillarum browni | - | 8 | E |
| Tern, common | Sterna hirundo | - | 3 | SC |
| Tern, elegant | Sterna elegans | - | 1 | SC |
| Tern, least | Sterna antillarum | U.S.A. (AR, CO, IA, IL, IN, KS, KY, LA_Miss. R. and tribs. N of Baton Rouge, MS_Miss. R., MO, MT, ND, NE, NM, OK, SD, TN, TX_except within 50 miles of coast) | 3 | E |
| Tern, roseate | Sterna dougallii dougallii | Western Hemisphere and adjacent oceans, incl. U.S.A. (FL, PR, VI), where not listed as endangered | 4 | T |
| Tern, roseate | Sterna dougallii dougallii | U.S.A. (Atlantic Coast south to NC), Canada (Newf., N.S, Que.), Bermuda | 5 | E |
| Tern, Van Rossem's gull-billed | Sterna nilotica vanrossemi | - | 8 | UR |
| Terrapin, Mississippi diamondback | Malaclemys terrapin pileata | - | 4 | SC |
| Terrapin, northern diamondback | Malaclemys terrapin terrapin | - | 5 | SC |
| Terrapin, river | Batagur baska | - | Foreign | E |
| Terrapin, Texas diamondback | Malaclemys terrapin littoralis | - | 2 | SC |
| Tetracoccus, holly-leaved | Tetracoccus ilicifolius | - | 1 | RT |
| Tetracoccus, Parry's | Tetracoccus dioicus | - | 1 | SC |
| Tetraplasandra, Wai`anae | Tetraplasandra waianensis | - | 1 | RT |
| Thelypody, Fresno Creek | Thelypodium tenue | - | 2 | SC |
| Thelypody, Howell's spectacular | Thelypodium howellii spectabilis | - | 1 | T |
| Thelypody, Jaeger's | Thelypodium repandum | - | 1 | SC |
| Thelypody, short-podded | Thelypodium brachycarpum | - | 1 | RT |
| Thelypody, [unnamed] | Thelypodium texanum | - | 2 | RT |
| Thistle | Cirsium brevifolium | - | 1 | RT |
| Thistle Mountain-slope | Cirsium scapanolepis | - | 6 | SC |
| Thistle, Ashland | Cirsium ciliolatum | - | 1 | RT |
| Thistle, Chorro Creek bog | Cirsium fontinale var. obispoense | - | 8 | E |
| Thistle, Clokey's | Cirsium clokeyi | - | 1 | RT |
| Thistle, compact cobweb | Cirsium occidentale compactum | - | 1 | SC |
| Thistle, fountain | Cirsium fontinale var. fontinale | - | 8 | E |
| Thistle, La Graciosa | Cirsium loncholepis | - | 8 | E |
| Thistle, Loch Lomond coyote | Eryngium constancei | - | 8 | E |
| Thistle, Mogollon | Cirsium parryi mogollonicum | - | 2 | SC |
| Thistle, Mt. Hamilton | Cirsium fontinale campylon | - | 1 | SC |
| Thistle, Mt. Tamalpais | Cirsium hydrophilum vaseyi | - | 1 | SC |
| Thistle, Ownbey's | Cirsium ownbeyi | - | 6 | SC |
| Thistle, Pitcher's | Cirsium pitcheri | - | 3 | T |
| Thistle, Sacramento Mountains | Cirsium vinaceum | - | 2 | T |
| Thistle, slough | Cirsium crassicaule | - | 1 | SC |
| Thistle, Suisun | Cirsium hydrophilum var. hydrophilum | - | 8 | E |
| Thistle, surf | Cirsium rhothophilum | - | 1 | RT |
| Thistle, Virgin | Cirsium virginensis | - | 6 | SC |
| Thistle, Wright's marsh | Cirsium wrightii | - | 2 | UR |
| Thistle, [unnamed] | Cirsium davisii | - | 1 | RT |
| Thistle, [unnamed] | Cirsium hallii | - | 1 | RT |
| Thistle, [unnamed] | Cirsium hillii | - | 3 | SC |
| Thistle, [unnamed] | Cirsium longistylum | - | 6 | SC |
| Thistle, [unnamed] | Cirsium rydbergii | - | 6 | RT |
| Thistle, [unnamed] | Cirsium turneri | - | 2 | RT |
| Thornmint, San Benito | Acanthomintha obovata obovata | - | 1 | SC |
| Thornmint, San Diego | Acanthomintha ilicifolia | - | 8 | T |
| Thornmint, San Mateo | Acanthomintha obovata ssp. duttonii | - | 8 | E |
| Thoroughwort, Cape Sable | Chromolaena frustrata | - | 4 | C |
| Thoroughwort, white-bracted, New England | Eupatorium leucolepis novae-angliae | - | 5 | SC |
| Thoroughwort, [unnamed] | Eupatorium resinosum kentuckiense | - | 4 | RT |
| thrasher, Crissal | toxostoma crissale | - | 6 | SC |
| thrasher, Le Conte's | toxostoma lecontei | - | 8 | SC |
| Thrasher, San Joaquin LeConte's | Toxostoma lecontei macmillanorum | - | 1 | SC |
| Thrasher, white-breasted | Ramphocinclus brachyurus | - | Foreign | E |
| Thread bug, ana wingless | Nesidiolestes ana | - | 1 | SC |
| Thread bug, Mt. Tantalus wingless | Nesidiolestes insularis | - | 1 | SC |
| Thread bug, pulchrus | Empicoris pulchrus | - | 1 | SC |
| Thread bug, Robert's wingless | Nesidiolestes roberti | - | 1 | SC |
| Thread bug, Selium wingless | Nesidiolestes selium | - | 1 | SC |
| Three-awned grass, southern | Aristida simpliciflora | - | 4 | SC |
| Three-awned grass, [unnamed] | Aristida floridana | - | 4 | RT |
| Three-ridge, fat (mussel) | Amblema neislerii | - | 4 | E |
| Threetooth, Cape Fear | Triodopsis soelneri | - | 4 | SC |
| Thrush, Bicknell's | Catharus minimus bicknelli | - | 5 | SC |
| Thrush, large Kauai (=kamao) | Myadestes myadestinus | - | 1 | E |
| Thrush, Molokai | Myadestes lanaiensis rutha | - | 1 | E |
| Thrush, New Zealand (wattlebird) | Turnagra capensis | - | Foreign | E |
| Thrush, small Kauai (=puaiohi) | Myadestes palmeri | - | 1 | E |
| Thrush, St. Lucia Forest | Cichlherminia iherminieri santaeluciae | - | Foreign | PE |
| Thrush, Taita | Turdus olivaceus helleri | - | Foreign | E |
| Tick-trefoil, creamy | Desmodium ochroleucum | - | 4 | SU |
| Tick-trefoil, ground-spreading | Desmodium humifusum | - | 5 | SC |
| Tickle-tongue, Shinner's | Zanthoxylum parvum | - | 2 | RT |
| Tickseed, golden wave | Coreopsis intermedia | - | 4 | SC |
| Tickseed, Lindheimer's | Desmodium lindheimeri | - | 2 | SC |
| Tiger | Panthera tigris | - | Foreign | E |
| Tiger beetle, Barbara Ann's | Cicindela politula barbarannae | - | 2 | UR |
| Tiger beetle, Cazier's | Cicindela cazieri | - | 2 | SC |
| Tiger beetle, cobblestone | Cicindela marginipennis | - | 5 | SC |
| Tiger beetle, Columbia River | Cicindela columbica | - | 1 | RT |
| Tiger beetle, Coral Pink Sand Dunes | Cicindela albissima | - | 6 | C |
| Tiger beetle, greenest | Cicindela tranquebarica viridissima | - | 1 | SC |
| Tiger beetle, Guadalupe Mountains | Cicindela politula petrophila | - | 2 | UR |
| Tiger beetle, highlands | Cicindela highlandensis | - | 4 | C |
| Tiger beetle, Idaho dunes | Cicindela arenicola | - | 1 | SC |
| Tiger beetle, Los Olmos | Cicindela nevadica olmosa | - | 2 | SC |
| Tiger beetle, Maricopa | Cicindela oregona maricopa | - | 2 | SC |
| Tiger beetle, neojuvenile | Cicindela obsoleta neojuvenalis | - | 2 | SC |
| Tiger beetle, northeastern beach | Cicindela dorsalis dorsalis | - | 5 | T |
| Tiger beetle, oblivious | Cicindela latesignata obliviosa | - | 1 | SC |
| Tiger beetle, Ohlone | Cicindela ohlone | - | 8 | E |
| Tiger beetle, Puritan | Cicindela puritana | - | 5 | T |
| Tiger beetle, Sacramento Valley | Cicindela hirticollis abrupta | entire | 8 | RT |
| Tiger beetle, Salt Creek | Cicindela nevadica lincolniana | - | 6 | E |
| Tiger beetle, San Joaquin | Cicindela tranquebarica ssp. | - | 1 | SC |
| Tiger beetle, sandy beach | Cicindela hirticollis gravida | - | 1 | SC |
| Tiger beetle, Smyth's | Cicindela chlorocephala smythi | - | 2 | SC |
| Tiger beetle, subtropical blue-black | Cicindela nigrocoerula subtropica | - | 2 | SC |
| Tiger, Tasmanian | Thylacinus cynocephalus | - | Foreign | E |
| Tight coin, Yates' | Ammonitella yatesi | - | 1 | SC |
| Tightcoil Southern | Ogaridiscus subrupicola | - | 6 | SC |
| tightcoil, Crater Lake | Pristiloma arcticum ssp. crateris | - | 1 | SU |
| Tinamou, Kalinowski's | Nothoprocta kalinowskii | - | NA | SU |
| Tinamou, solitary | Tinamus solitarius | - | Foreign | E |
| Tit-spinetail, white-browed | Leptasthenura xenothorax | - | Foreign | PE |
| Tit-tyrant, ash-breasted | Anairetes alpinus | - | NA | PE |
| Toad, Amargosa | Bufo nelsoni | - | 8 | UR |
| Toad, Arizona | Bufo microscaphus microscaphus | - | 2 | SC |
| Toad, arroyo (=arroyo southwestern) | Bufo californicus (=microscaphus) | - | 8 | E |
| Toad, black | Bufo exsul | - | 1 | SC |
| toad, Boreal | Anaxyrus boreas boreas | Southern Rocky Mountain DPS | 6 | RT |
| Toad, Cameroon | Bufo superciliaris | - | Foreign | E |
| toad, Colorado River | bufo alvarius | - | 6 | SC |
| toad, Couch's spadefoot | scaphiopus couchii | - | 6 | SC |
| Toad, Houston | Bufo houstonensis | - | 2 | E |
| Toad, Monte Verde golden | Bufo periglenes | - | Foreign | E |
| Toad, Puerto Rican crested | Peltophryne lemur | - | 4 | T |
| Toad, Sonoran green | Bufo retiformis | - | 2 | RT |
| Toad, Western | Bufo boreas | - | 1 | SC |
| Toad, Wyoming | Bufo baxteri (=hemiophrys) | - | 6 | E |
| Toad, Yosemite | Bufo canorus | - | 8 | C |
| Toads, African viviparous | Nectophrynoides spp. | - | Foreign | E |
| Tody-tyrant, Kaempfer's | Hemitriccus kaempferi | - | NA | PE |
| Tomistoma | Tomistoma schlegelii | - | Foreign | E |
| Toothwort, yellow-tubered | Cardamine gemmata | - | 1 | SC |
| Topminnow, barrens | Fundulus julisia | - | 4 | RT |
| Topminnow, Gila (incl. Yaqui) | Poeciliopsis occidentalis | U.S.A. only | 2 | E |
| Topminnow, Plains | Fundulus sciadicus | - | 6 | SC |
| Topminnow, whiteline | Fundulus albolineatus | - | 4 | RT |
| Torreya, Florida | Torreya taxifolia | - | 4 | E |
| Tortoise, angulated | Geochelone yniphora | - | Foreign | E |
| Tortoise, Bolson | Gopherus flavomarginatus | - | Foreign | E |
| Tortoise, desert | Gopherus agassizii | Entire, except AZ south and east of Colorado River, and Mexico | 8 | T |
| Tortoise, desert | Gopherus agassizii | AZ south and east of Colorado River, and Mexico, when found outside of Mexico or said range in AZ | 8 | SAT |
| Tortoise, desert | Gopherus agassizii | Sonoran | 2 | UR |
| Tortoise, Galapagos | Geochelone nigra (=elephantopus) | - | Foreign | E |
| Tortoise, gopher | Gopherus polyphemus | Wherever found west of Mobile and Tombigbee Rivers in AL, MS, and LA | 4 | T |
| Tortoise, gopher | Gopherus polyphemus | eastern | 4 | UR |
| Tortoise, gopher | Gopherus polyphemus | U.S.A. (Florida) | 4 | SU |
| Tortoise, Madagascar radiated | Geochelone radiata | - | Foreign | E |
| Tortricid moth, Stevens' | Decodes stevensi | - | 6 | SC |
| Tortugo, prieto | Ravenia urbanii | - | 4 | RT |
| Tortula, Ammon's | Tortula ammonsiana | - | 4 | SC |
| Totoaba (seatrout or weakfish) | Cynoscion macdonaldi | - | Foreign | E |
| Toucanet, yellow-browed | Aulacorhynchus huallagae | - | Foreign | UR |
| Towhee, Inyo California | Pipilo crissalis eremophilus | - | 8 | T |
| Towhee, San Clemente | Pipilo erythrophthalmus clementae | - | 1 | SC |
| Towhee, Yuma brown | Pipilo fuscus relictus | - | 2 | RT |
| Townsendia, Last Chance | Townsendia aprica | - | 6 | T |
| Townsendia, sp. nov. ined. (gypsum) | Townsendia sp. | NM | 2 | SC |
| Townsendia, sp. nov. ined. (Nye Co.) | Townsendia sp. | Nye Co. | 1 | RT |
| Townsendia, sp. nov. ined. (WY) | Townsendia sp. | WY | 2 | SC |
| Townsendia, sword | Townsendia spathulata | - | 6 | RT |
| Townsendia, [unnamed] | Townsendia jonesii lutea | - | 6 | SC |
| Townsendia, [unnamed] | Townsendia mensana | - | 6 | RT |
| Townsendia, [unnamed] | Townsendia rothrockii | - | 6 | RT |
| Tracaja | Podocnemis unifilis | - | Foreign | E |
| Tracyina, beaked | Tracyina rostrata | - | 1 | RT |
| Tre, lupine, San Mateo | Lupinus arboreus eximius | - | 1 | SC |
| Tree poppy, Channel Island | Dendromecon rigida harfordii | - | 1 | SC |
| Tree poppy, island | Dendromecon rigida rhamnoides | - | 1 | SC |
| Tree snail, Moloka`i | Partulina virgulata | - | 1 | SC |
| Tree snail, Newcomb's | Newcombia canaliculata | - | 1 | SC |
| Tree snail, Newcomb's | Newcombia cumingi | - | 1 | C |
| Tree snail, Newcomb's | Newcombia perkinsi | - | 1 | SC |
| Tree snail, Newcomb's | Newcombia pfeifferi | - | 1 | SC |
| Tree snail, Newcomb's | Newcombia sulcata | - | 1 | SC |
| Tree snail, Newcomb's | Nucombia plicata | - | 1 | SC |
| Tree-fern (Tsatsa) | Cyathea lunulata | - | NA | SU |
| Tree-Finch, Floreana | Camarhynchus pauper | - | Foreign | PE |
| Treefrog, Arizona | Hyla wrightorum | Huachuca/Canelo Population | 2 | C |
| Treefrog, pine barrens | Hyla andersonii | Florida | 4 | DO |
| Trefoil, Heller's bird's-foot | Lotus unifoliolatus var. helleri | - | 4 | SC |
| Trembler, Martinique (thrasher) | Cinclocerthia ruficauda gutturalis | - | Foreign | E |
| trichocoronis, Wright's | trichocoronis wrightii | - | 6 | SC |
| Trillium, least, Ozark | Trillium pusillum ozarkanum | - | 4 | SC |
| Trillium, least, Virginia | Trillium pusillum virginianum | - | 5 | SC |
| Trillium, persistent | Trillium persistens | - | 4 | E |
| Trillium, relict | Trillium reliquum | - | 4 | E |
| Trillium, Texas | Trillium pusillum texanum | - | 2 | SC |
| Tropidocarpum, caper-fruited | Tropidocarpum capparideum | - | 1 | SC |
| Trout, Alvord cutthroat | Oncorhynchus clarki ssp. | Alvord | 1 | RT |
| Trout, Apache | Oncorhynchus apache | - | 2 | T |
| Trout, Bonneville cutthroat | Oncorhynchus clarki utah | - | 6 | RT |
| trout, brook | Salvelinus fontinalis | anadromous (lake-run) | 3 | RT |
| Trout, bull | Salvelinus confluentus | U.S.A., conterminous, (lower 48 states) | 1 | T |
| Trout, California golden trout | Oncorhynchus mykiss aguabonita | - | 1 | UR |
| Trout, Catlow Valley redband | Oncorhynchus mykiss ssp. | Catlow Valley | 1 | SC |
| Trout, coastal cutthroat | Oncorhynchus clarki clarki | Umpqua R. (U.S.A._OR) naturally spawning populations in mainstem and tributaries | 1 | DR |
| trout, Coastal rainbow | oncorhynchus mykiss ssp. irideus | - | 7 | SC |
| Trout, Colorado River cutthroat | Oncorhynchus clarki pleuriticus | - | 6 | RT |
| Trout, Columbia River redband | Oncorhynchus mykiss gairdneri | - | 1 | RT |
| Trout, Eagle Lake rainbow | Oncorhynchus mykiss aquilarum | entire | 8 | UR |
| Trout, Gila | Oncorhynchus gilae | - | 2 | T |
| Trout, Goose Lake redband | Oncorhynchus mykiss ssp. | Goose Lake | 1 | SC |
| Trout, Great Basin redband | Oncorhynchus mykiss ssp. | - | 1 | RT |
| Trout, greenback cutthroat | Oncorhynchus clarki stomias | - | 6 | T |
| Trout, interior redband | Oncorhynchus mykiss gibbsi | - | 1 | SC |
| Trout, Kern River rainbow | Oncorhynchus mykiss gilberti | - | 1 | SC |
| Trout, Lahontan cutthroat | Oncorhynchus clarki henshawi | - | 8 | T |
| Trout, Little Kern golden | Oncorhynchus aguabonita whitei | - | 8 | T |
| Trout, McCloud R. redband | Oncorhynchus mykiss ssp. | McCloud R. | 1 | RT |
| Trout, Paiute cutthroat | Oncorhynchus clarki seleniris | - | 8 | T |
| Trout, Rio Grande cutthroat | Oncorhynchus clarki virginalis | - | 2 | C |
| Trout, silver | Salvelinus agassizi | - | 5 | RT |
| Trout, Snake River fine-spotted cutthroat | Oncorhynchus clarki ssp. | Snake River | 1 | SC |
| Trout, Warner Valley redband | Oncorhynchus mykiss ssp. | - | 1 | SC |
| Trout, westslope cutthroat | Oncorhynchus clarki lewisi | - | 6 | RT |
| Trout, Willow/Whitehorse cutthroat | Oncorhynchus clarki ssp. | Willow/Whitehorse | 1 | RT |
| Trout, yellowfin cutthroat | Oncorhynchus clarki macdonaldi | - | 6 | RT |
| Trout, Yellowstone cutthroat | Oncorhynchus clarki bouvieri | - | 6 | RT |
| Trumpet, Rawson's flaming | Collomia rawsoniana | - | 1 | SC |
| Trumpets, Texas | Acleisanthes crassifolia | - | 2 | SC |
| Tryonia, Amargosa | Tryonia variegata | - | 8 | UR |
| Tryonia, Brune's | Tryonia brunei | - | 2 | SC |
| Tryonia, Grapevine Springs elongate | Tryonia margae | - | 1 | SC |
| Tryonia, Grapevine Springs squat | Tryonia rowlandsi | - | 1 | SC |
| Tryonia, grated | Tryonia clathrata | - | 8 | UR |
| Tryonia, mimic | Tryonia imitator | - | 1 | SC |
| Tryonia, minute | Tryonia ericae | - | 8 | UR |
| Tryonia, Point of Rocks | Tryonia elata | - | 8 | UR |
| Tryonia, Quitobaquito | Tryonia quitobaquitae | - | 2 | SC |
| Tryonia, robust | Tryonia robusta | - | 1 | SC |
| Tryonia, sportinggoods | Tryonia angulata | - | 1 | UR |
| Tuatara | Sphenodon punctatus | - | Foreign | E |
| Tuatara, Brother's Island | Sphenodon guntheri | - | Foreign | E |
| Tuctoria, Greene's | Tuctoria greenei | - | 8 | E |
| Tui chub, Lahontan Creek | Gila bicolor obesa | - | 1 | RT |
| Tule perch, Russian River | Hysterocarpus traski pomo | - | 1 | SC |
| Tule-pea, Delta | Lathyrus jepsonii jepsonii | - | 1 | SC |
| Turaco, Bannerman's | Tauraco bannermani | - | Foreign | E |
| Turkish rugging | Chorizanthe staticoides chrysacantha | - | 1 | RT |
| Turtle dove, Seychelles | Streptopelia picturata rostrata | - | Foreign | E |
| Turtle, Alabama red-belly | Pseudemys alabamensis | - | 4 | E |
| Turtle, alligator snapping | Macroclemys temmincki | - | 4 | UR |
| Turtle, aquatic box | Terrapene coahuila | - | Foreign | E |
| Turtle, Arizona yellow mud | Kinosternon flavescens arizonense | - | 2 | RT |
| Turtle, Barbour's map | Graptemys barbouri | - | 4 | RT |
| Turtle, Big Bend mud | Kinosternon hirtipes murrayi | - | 2 | SC |
| Turtle, black softshell | Trionyx nigricans | - | Foreign | E |
| Turtle, black-knobbed map | Graptemys nigrinoda | - | 4 | RT |
| Turtle, Blanding's | Emydoidea blandingii | - | 6 | SC |
| Turtle, bog (=Muhlenberg) | Clemmys muhlenbergii | U.S.A. (GA, NC, SC, TN, VA) | 5 | SAT |
| Turtle, bog (=Muhlenberg) | Clemmys muhlenbergii | Entire, except GA, NC, SC, TN, VA | 5 | T |
| Turtle, Brazilian sideneck | Phrynops hogei | - | Foreign | E |
| Turtle, Burmese peacock | Morenia ocellata | - | Foreign | E |
| Turtle, Cagle's map | Graptemys caglei | - | 2 | RT |
| Turtle, Cat Island | Trachemys terrapen | Cat Island in the Bahamas | Foreign | E |
| Turtle, Central American river | Dermatemys mawii | - | Foreign | E |
| Turtle, Cuatro Cienegas softshell | Trionyx ater | - | Foreign | E |
| Turtle, false map | Graptemys pseudogeographica | - | 6 | SC |
| Turtle, flattened musk | Sternotherus depressus | Black Warrior R. system upstream from Bankhead Dam | 4 | T |
| Turtle, geometric | Psammobates geometricus | - | Foreign | E |
| Turtle, Illinois mud | Kinosternon flavescens spooneri | - | 3 | RT |
| Turtle, Inagua Island | Trachemys stejnegeri malonei | - | Foreign | E |
| Turtle, Indian flap-shelled | Lissemys punctata punctata | - | Foreign | DO |
| Turtle, Indian sawback | Kachuga tecta tecta | - | Foreign | E |
| Turtle, Indian softshell | Trionyx gangeticus | - | Foreign | E |
| Turtle, Key striped mud | Kinosternon bauri bauri | - | 4 | RT |
| Turtle, Mississippe redbelly | Pseudemys sp. | - | 4 | SC |
| Turtle, northwestern pond | Clemmys marmorata marmorata | - | 1 | SC |
| Turtle, Pascagoula map | Graptemys gibbonsi | - | 4 | SU |
| Turtle, peacock softshell | Trionyx hurum | - | Foreign | E |
| Turtle, ringed map | Graptemys oculifera | - | 4 | T |
| Turtle, Sabine Ouachita map | Graptemys ouachitensis sabinensis | - | 2 | RT |
| Turtle, short-necked or western swamp | Pseudemydura umbrina | - | Foreign | E |
| Turtle, Sonoyta mud | Kinosternon sonoriense longifemorale | - | 2 | C |
| Turtle, South American red-lined | Trachemys scripta callirostris | - | Foreign | E |
| Turtle, southwestern pond | Clemmys marmorata pallida | - | 1 | SC |
| Turtle, spotted pond | Geoclemys hamiltonii | - | Foreign | E |
| Turtle, Texas map | Graptemys versa | - | 2 | RT |
| Turtle, three-keeled Asian | Melanochelys tricarinata | - | Foreign | E |
| Turtle, western pond | Clemmys marmorata | - | NA | UR |
| Turtle, wood | Clemmys insculpta | - | NA | RT |
| Turtle, yellow mud | Kinosternon flavescens flavescens | - | 3 | SC |
| Turtle, yellow-blotched map | Graptemys flavimaculata | - | 4 | T |
| turtlehead, Cuthbert's | chelone cuthbertii | - | 4 | SC |
| Twayblade, auricled | Listera auriculata | - | 5 | RT |
| Twinpod Duchesne River | Physaria stylosa | - | 6 | SC |
| Twinpod Repand | Physaria repanda | - | 6 | SC |
| Twinpod, dense | Physaria condensata | - | 6 | RT |
| Twinpod, Dudley Bluffs | Physaria obcordata | - | 6 | T |
| Twinpod, Graham's | Physaria grahamii | - | 6 | RT |
| Twinpod, [unnamed] | Physaria integrifolia monticola | - | 6 | SC |
| Twinpod, [unnamed] | Physaria saximontana saximontana | - | 6 | SC |
| Twistflower, bracted | Streptanthus bracteatus | - | 2 | SC |
| Twistflower, Cutler's | Streptanthus cutleri | - | 2 | SC |
| Tyrannulet, Bananal | Serpophaga araguayae | - | NA | SU |
| Uakari (all species) | Cacajao spp. | - | Foreign | E |
| Ufa-halomtano | Heritiera longipetiolata | - | 1 | RT |
| Uhiuhi | Caesalpinia kavaiense | - | 1 | E |
| Ulunahele | Cyrtandra kauaiensis | - | 1 | RT |
| Underwing, precious | Catocala pretiosa pretiosa | - | 5 | SC |
| Unicorn plant, dune | Proboscidea sabulosa | - | 2 | RT |
| Unicorn plant, many-flowered | Proboscidea spicata | - | 2 | SC |
| Urial | Ovis musimon ophion | - | Foreign | E |
| Uvillo | Eugenia haematocarpa | - | 4 | E |
| Valerian, Guadalupe | Valeriana texana | - | 2 | RT |
| Valerian, marsh | Valeriana uliginosa | - | 4 | RT |
| Vanga, Pollen's | Xenopirostris polleni | - | Foreign | T |
| Vanga, Van Dam's | Xenopirostris damii | - | Foreign | T |
| Venus' fly-trap, [unnamed] | Dionaea muscipula | - | 4 | SC |
| Verbena Yellowstone Sand | Abronia ammophila | - | 6 | UR |
| Vertigo, Alabama | Vertigo alabamensis | - | 4 | SC |
| Vertigo, callused | Vertigo arthuri | - | 6 | SC |
| vertigo, Hoko | Vertigo sp | - | 1 | SU |
| Vertigo, Hubricht's | Vertigo hubrichti | - | 3 | SC |
| Vertigo, Iowa Pleistocene | Vertigo sp. | - | 3 | SC |
| Vertigo, Keys | Vertigo hebardi | - | 4 | SC |
| Vertigo, Meramac River | Vertigo meramacensis | - | 3 | SC |
| Vertigo, occult | Vertigo occulta | - | 3 | SC |
| Vertigo, ovate | Vertigo ovata | - | 2 | SC |
| Vervain, Red Hills | Verbena californica | - | 8 | T |
| vervain, Riverbank | Verbena riparia | - | 5 | SC |
| Vervain, [unnamed] | Verbena tampensis | - | 4 | SC |
| Vespid | Euparagia | entire | 8 | RT |
| Vetch, hairy pod | Vicia reverchonii | - | 2 | RT |
| Vetch, Hawaiian | Vicia menziesii | - | 1 | E |
| Vetch, Ocala | Vicia ocalensis | - | 4 | SC |
| Vetchling, Grimes | Lathyrus grimesii | - | 1 | RT |
| Viceroy, Nevada | Limenitus archippus lahontani | - | 1 | SC |
| Vicuna | Vicugna vicugna | - | Foreign | E |
| viguiera, San Diego County | viguiera laciniata | - | 1 | SC |
| Violet, felt-leaf | Viola tomentosa | - | 1 | RT |
| Violet, Flett's | Viola flettii | - | 1 | RT |
| Violet, Frank Smith's | Viola franksmithii | - | 6 | SC |
| Violet, Guadalupe Mountain | Viola guadalupensis | - | 2 | SC |
| Violet, limestone | Viola purpurea charlestonensis | - | 1 | RT |
| Violet, New England | Viola novae-angliae | - | 3 | RT |
| Violet, western bog | Viola primulifolia occidentalis | - | 1 | SC |
| Viper, Lar Valley | Vipera latifii | - | Foreign | E |
| Vireo, Arizona Bell's | Vireo bellii arizonae | - | 2 | RT |
| Vireo, black-capped | Vireo atricapilla | - | 2 | E |
| vireo, Gray | Vireo vicinior | - | 8 | SC |
| Vireo, least Bell's | Vireo bellii pusillus | - | 8 | E |
| Virgin's bower, Addison's | Clematis addisonii | - | 5 | SC |
| Virgin's bower, [unnamed] | Clematis gattingeri | - | 4 | RT |
| Viznaga | Ferocactus acanthodes acanthodes | - | 1 | RT |
| vole dusky tree | Aborimus longicaudus ssp. silvicola | - | 1 | UR |
| Vole, Amak tundra | Microtus oeconomus amakensis | - | 7 | SC |
| Vole, Amargosa | Microtus californicus scirpensis | - | 8 | E |
| Vole, Arizona montane | Microtus montanus arizonensis | - | 2 | RT |
| Vole, Ash Meadows montane | Microtus montanus nevadensis | - | 1 | SC |
| Vole, beach | Microtus breweri | - | 5 | SC |
| Vole, Block Island meadow | Microtus pennsylvanicus provectus | - | 5 | SC |
| Vole, California red tree | Arborimus pomo | - | 1 | SC |
| Vole, Florida salt marsh | Microtus pennsylvanicus dukecampbelli | - | 4 | E |
| Vole, Graham Mountains long-tailed | Microtus longicaudus leucophaeus | - | 2 | RT |
| Vole, Hualapai Mexican | Microtus mexicanus hualpaiensis | - | 2 | E |
| Vole, Kentucky red-backed | Clethrionomys gapperi maurus | - | 4 | SC |
| Vole, Kittatiny red-backed | Clethrionomys gapperi rupicola | - | 5 | RT |
| Vole, Louisiana prairie | Microtus ochrogaster ludovicianus | - | 4 | RT |
| Vole, Mojave river | Microtus californicus mohavensis | - | 1 | SC |
| Vole, Montague tundra | Microtus oeconomus elymocetes | - | 7 | SC |
| Vole, Navaho Mountain Mexican | Microtus mexicanus navaho | - | 2 | SC |
| Vole, Owens Valley California | Microtus californicus vallicola | - | 1 | SC |
| Vole, Pahranagat Valley montane | Microtus montanus fucosus | - | 1 | SC |
| Vole, Penobscot meadow | Microtus pennsylvanicus shattucki | - | 5 | SC |
| Vole, potholes meadow | Microtus pennsylvanicus kincaidi | - | 1 | SC |
| Vole, Pymatuning red-backed | Clethrionomys gapperi paludicola | - | 5 | RT |
| Vole, San Pablo California | Microtus californicus sanpabloensis | - | 1 | RT |
| Vole, Shaw Island Townsend's | Microtus townsendii pugeti | - | 1 | RT |
| Vole, southern rock | Microtus chrotorrhinus carolinensis | - | 5 | SC |
| Vole, St. Mathew | Microtus abbreviatus | - | 7 | SU |
| Vole, Stephens' California | Microtus californicus stephensi | - | 1 | SC |
| Vole, Virgin River montane | Microtus montanus rivularis | - | 6 | SC |
| Vole, white-footed | Arborimus albipes | - | 1 | SC |
| Vole, Woodland | Microtus pinetorum | - | NA | SU |
| vulture, Turkey | cathartes aura | - | 7 | SC |
| Wahane | Pritchardia aylmer-robinsonii | - | 1 | E |
| Wahaula heiau | Rauvolfia remotiflora | - | 1 | RT |
| Wake robin, Salmon Mountains | Trillium ovatum oettingeri | - | 1 | RT |
| Wallaby, banded hare | Lagostrophus fasciatus | - | Foreign | E |
| Wallaby, brindled nail-tailed | Onychogalea fraenata | - | Foreign | E |
| Wallaby, crescent nail-tailed | Onychogalea lunata | - | Foreign | E |
| Wallaby, Parma | Macropus parma | - | Foreign | E |
| Wallaby, western hare | Lagorchestes hirsutus | - | Foreign | E |
| Wallaby, yellow-footed rock | Petrogale xanthopus | - | Foreign | E |
| Walleye, southeastern | Stizostedion vitreum vitreum | Mobile River Drainage | 4 | RT |
| Wallflower, Ben Lomond | Erysimum teretifolium | - | 8 | E |
| Wallflower, coast | Erysimum ammophilum | - | 1 | SC |
| Wallflower, Contra Costa | Erysimum capitatum var. angustatum | - | 8 | E |
| Wallflower, island | Erysimum insulare insulare | - | 1 | SC |
| Wallflower, Menzies' | Erysimum menziesii | - | 8 | E |
| Wallflower, San Francisco | Erysimum franciscanum | - | 1 | SC |
| Wallflower, [unnamed] | Erysimum asperum angustatum | - | 7 | RT |
| Walnut (=Nogal), West Indian | Juglans jamaicensis | - | 4 | E |
| walnut, California | Juglans californica var. californica | - | 1 | SC |
| Walnut, Northern California black | Juglans californica hindsii | - | 1 | SC |
| Walrus, Pacific | Odobenus rosmarus ssp. divergens | - | 7 | UR |
| Wanderer, plain (=collared-hemipode) | Pedionomous torquatus | - | Foreign | E |
| Warbler (=wood), Bachman's | Vermivora bachmanii | - | 4 | E |
| Warbler (=wood), Barbados yellow | Dendroica petechia petechia | - | Foreign | E |
| Warbler (=wood), golden-cheeked | Dendroica chrysoparia | - | 2 | E |
| Warbler (=wood), Kirtland's | Dendroica kirtlandii | - | 3 | E |
| Warbler (=wood), Semper's | Leucopeza semperi | - | Foreign | E |
| Warbler, Aldabra (old world warbler) | Nesillas aldabranus | - | Foreign | E |
| Warbler, cerulean | Dendroica cerulea | - | 3 | RT |
| Warbler, Colima | Vermivora crissalis | - | 2 | RT |
| Warbler, Eiao Polynesian | Acrocephalus percernis aquilonis | - | Foreign | PE |
| Warbler, elfin-woods | Dendroica angelae | - | 4 | C |
| Warbler, Golden-winged | Vermivora chrysoptera | - | 3 | SU |
| Warbler, long-legged | Trichocichla rufa | - | Foreign | E |
| Warbler, Lucy's | Vermivora luciae | - | 1 | SU |
| warbler, Macgillivray's | oporornis tolmiei | - | 7 | SC |
| Warbler, Moorea Polynesian | Acrocephalus caffer longirostris | - | Foreign | UR |
| warbler, Nashville | vermivora ruficapilla | - | 4 | SC |
| Warbler, nightingale reed (old world warbler) | Acrocephalus luscinia | - | 1 | E |
| Warbler, Rodrigues (old world warbler) | Bebrornis rodericanus | - | Foreign | E |
| Warbler, Seychelles (old world warbler) | Bebrornis sechellensis | - | Foreign | E |
| warbler, Sonoran yellow | dendroica petechia ssp. sonorana | - | 6 | SC |
| Warbler, Stoddard's yellow-throated | Dendroica dominica stoddardi | - | 4 | SC |
| warbler, Wilson's | wilsonia pusilla | - | 7 | SC |
| warbler, Yellow | dendroica petechia ssp. brewsteri | - | 7 | SC |
| Warea, sessile-leaved | Warea sessilifolia | - | 4 | RT |
| Warea, wide-leaf | Warea amplexifolia | - | 4 | E |
| Wartyback, white (pearlymussel) | Plethobasus cicatricosus | U.S.A. (TN - specified portions of the French Broad and Holston Rivers; see 17.85(b)(1)) | 4 | EXPN |
| Wartyback, white (pearlymussel) | Plethobasus cicatricosus | - | 4 | E |
| Wasp, Antioch mutillid | Myrmosula pacifica | - | 1 | SC |
| Wasp, Antioch potter | Microdynerus arenicolus | - | 1 | RT |
| Wasp, Antioch sphecid | Philanthus nasalis | - | 1 | SC |
| Wasp, black-winged odynerus vespid | Odynerus nigripennis | - | 1 | SC |
| Wasp, Kauai nesomimesan sphecid | Nesomimesa kauaiensis | - | 1 | SC |
| Wasp, Nihoa eupelmus | Eupelmus nihoaensis | - | 1 | SC |
| Wasp, Nihoa sclerodermus | Sclerodermus nihoaensis | - | 1 | SC |
| Wasp, Niihau odynerus vespid | Odynerus niihauensis | - | 1 | SC |
| Wasp, Perkins' nesomimesan sphecid | Nesomimesa perkinsi | - | 1 | SC |
| Wasp, radulan odynerus vespid | Odynerus radula | - | 1 | SC |
| Wasp, sand | Microbembex elegans | entire | 8 | RT |
| Wasp, sand | Stictiella villegasi | entire | 8 | RT |
| Wasp, shade-winged nesomimesan sphecid | Nesomimesa sciopteryx | - | 1 | SC |
| Wasp, soror odynerus vespid | Odynerus soror | - | 1 | SC |
| water flea, hairy | Dumontia oregonensis | - | 1 | SC |
| Water penny, Arizona | Psephenus arizonensis | - | 2 | SC |
| Water penny, White Mountains | Psephenus montanus | - | 2 | SC |
| Water scavenger beetle, Chiricahua | Cymbiodyta arizonica | - | 2 | SC |
| Water scavenger beetle, Leech's chaetarthrian | Chaetarthria leechi | - | 1 | SC |
| Water scavenger beetle, Ricksecker's | Hydrochara rickseckeri | - | 1 | SC |
| Water scavenger beetle, Seth Forest | Hydrochus sp. | - | 5 | SC |
| Water scavenger beetle, Utah chaetarthrian | Chaetarthria utahensis | - | 6 | SC |
| Water slater, Bennets Mill Cave | Caecidotea carolinensis | - | 4 | SC |
| Water-dropwort, giant | Oxypolis greenmanii | - | 4 | RT |
| Water-hemlock, Bolander | Cicuta bolanderi | - | 1 | RT |
| Water-hyssop, Chickahominy | Bacopa simulans | - | 5 | RT |
| Water-hyssop, mat-forming | Bacopa stragula | - | 5 | RT |
| Water-parsnip, Florida | Sium floridanum | - | 4 | SC |
| Water-plantain, Kral's | Sagittaria secundifolia | - | 4 | T |
| Water-umbel, Huachuca | Lilaeopsis schaffneriana var. recurva | - | 2 | E |
| Water-willow, Cooley's | Justicia cooleyi | - | 4 | E |
| Water-willow, Runyon's | Justicia runyonii | - | 2 | SC |
| Water-willow, thick-leaved | Justicia crassifolia | - | 4 | SC |
| Water-willow, Wright's | Justicia wrightii | - | 2 | SC |
| Water-willow, [unnamed] | Justicia mortuifluminis | - | 5 | RT |
| Watercress, Gambel's | Rorippa gambellii | - | 8 | E |
| Watercress, San Luis | Rorippa coloradensis | - | 6 | SC |
| Waterdog, black warrior (=Sipsey Fork) | Necturus alabamensis | - | 4 | C |
| Waterdog, Neuse River | Necturus lewisi | - | 4 | RT |
| Waterleaf, ballhead, Thompson's | Hydrophyllum capitatum thompsonii | - | 1 | RT |
| Waterweed, Nashville | Elodea linearis | - | 4 | RT |
| Waterweed, Nevada | Elodea nevadensis | - | 1 | RT |
| Waterweed, Schweinitz's | Elodea schweinitzii | - | 5 | SC |
| Waterweed, Truckee | Elodea brandegeae | - | 1 | RT |
| Wattle-eye, banded | Platysteira laticincta | - | Foreign | E |
| Wawae`iole | Huperzia (=Phlegmariurus) stemmermanniae | - | 1 | C |
| Wawae`iole | Huperzia mannii | - | 1 | E |
| Wawae`iole | Lycopodium (=Phlegmariurus) nutans | - | 1 | E |
| Weasel, Florida long-tailed | Mustela frenata peninsulae | - | 4 | SC |
| Weaver, Clarke's | Ploceus golandi | - | Foreign | E |
| Wedge, Arkansas | Triodopsis occidentalis | - | 4 | SC |
| Wedgemussel, dwarf | Alasmidonta heterodon | - | 5 | E |
| Weevil, Antioch Dune | Dysticheus rotundicollis | - | 1 | RT |
| Weevil, black rhyncogonus | Rhyncogonus stygius | - | 1 | SC |
| Weevil, Blackburn's pentarthrum | Pentarthrum blackburni | - | 1 | SC |
| Weevil, Blackburn's rhyncogonus | Rhyncogonus blackburni | - | 1 | SC |
| Weevil, Blaisdell trigonoscuta | Trigonoscuta blaisdelli | - | 1 | SC |
| Weevil, brown-tassel trigonoscuta | Trigonoscuta brunnotasselata | - | 1 | SC |
| Weevil, Coral Beach Sand Dune | Trigonoscuta dorothea corallana | - | NA | SU |
| Weevil, Dorothy's El Segundo Dune | Trigonoscuta dorothea dorothea | - | 1 | SC |
| Weevil, Doyen's trigonoscuta dune | Trigonoscuta sp. | - | 1 | SC |
| Weevil, Ford's rhyncogonus | Rhyncogonus segnis fordi | - | 1 | SC |
| Weevil, Fort Ross trigonoscuta | Trigonoscuta rossi | - | 1 | RT |
| Weevil, Giffard's rhyncogonus | Rhyncogonus giffardi | - | 1 | SC |
| Weevil, Gifford's nesotocus | Nesotocus giffordi | - | 1 | SC |
| Weevil, Kauai forest rhyncogonus | Rhyncogonus sylvicola | - | 1 | SC |
| Weevil, Kauai nesotocus | Nesotocus kauaiensis | - | 1 | SC |
| Weevil, Koebele's rhyncogonus | Rhyncogonus koebelei | - | 1 | SC |
| Weevil, Lahaina rhyncogonus | Rhyncogonus lahainae | - | 1 | SC |
| Weevil, Lanai rhyncogonus | Rhyncogonus lanaiensis | - | 1 | SC |
| Weevil, Lange's El Segundo Dune | Onychobaris langei | - | 1 | SC |
| Weevil, Laysan oodemas | Oodemas laysanensis | - | 1 | SC |
| Weevil, Laysan rhyncogonus | Rhyncogonus bryani | - | 1 | SC |
| Weevil, le`ie rhyncogonus | Rhyncogonus freycinetiae | - | 1 | SC |
| Weevil, Molokai rhyncogonus | Rhyncogonus molokaiensis | - | 1 | SC |
| Weevil, Munro's nesotocus | Nesotocus munroi | - | 1 | SC |
| Weevil, mutated rhyncogonus | Rhyncogonus mutatus | - | 1 | SC |
| Weevil, Necker oodemas | Oodemas neckeri | - | 1 | SC |
| Weevil, Necker rhyncogonus | Rhyncogonus biformis | - | 1 | SC |
| Weevil, Nelson's miloderes | Miloderes nelsoni | - | 1 | SC |
| Weevil, Nihoa oodemas | Oodemas breviscapum | - | 1 | SC |
| Weevil, Nihoa rhyncogonus | Rhyncogonus exsul | - | 1 | SC |
| Weevil, Nihoa stenotrupis | Stenotrupis pritchardiae | - | 1 | SC |
| Weevil, Oahu heteramphus fern | Heteramphus filicum | - | 1 | SC |
| Weevil, Oahu nesiotes | Deinocossonus nesiotes | - | 1 | SC |
| Weevil, obscure pentarthrum | Pentarthrum obscura | - | 1 | SC |
| Weevil, obsolete rhyncogonus | Rhyncogonus obsoletus | - | 1 | SC |
| Weevil, Olopua rhyncogonus | Rhyncogonus oleae | - | 1 | SC |
| Weevil, Roth's dune | Trigonoscuta rothi algodones | entire | 8 | RT |
| Weevil, Roth's dune | Trigonoscuta rothi imperialis | entire | 8 | RT |
| Weevil, Roth's dune | Trigonoscuta rothi punctata | entire | 8 | RT |
| Weevil, Roth's dune | Trigonoscuta rothi rothi | entire | 8 | RT |
| Weevil, Rulien's miloderes | Miloderes rulieni | - | 1 | SC |
| Weevil, Santa Catalina Island trigonscuta | Trigonoscuta catalina | - | 1 | SC |
| Weevil, Santa Cruz Island shore | Trigonoscuta stantoni | - | 1 | SC |
| Weevil, scaly rhyncogonus | Rhyncogonus squamiger | - | 1 | SC |
| Weevil, Sharp's rhyncogonus | Rhyncogonus sharpi | - | 1 | SC |
| Weevil, simple rhyncogonus | Rhyncogonus simplex | - | 1 | SC |
| Weevil, slow rhyncogonus | Rhyncogonus segnis segnis | - | 1 | SC |
| Weevil, striped rhyncogonus | Rhyncogonus vittatus | - | 1 | SC |
| Weevil, tubercled rhyncogonus | Rhyncogonus tuberculatus | - | 1 | SC |
| Weevil, wandering oodemas | Oodemas erro | - | 1 | SC |
| Weevil, Welch's rhyncogonus | Rhyncogonus welchii | - | 1 | SC |
| Weevil, Yorba Linda trigonoscuta | Trigonoscuta yorbalindae | - | 1 | RT |
| Whale, blue | Balaenoptera musculus | - | NMFS | E |
| Whale, bowhead | Balaena mysticetus | - | NMFS | E |
| Whale, finback | Balaenoptera physalus | - | NMFS | E |
| Whale, gray | Eschrichtius robustus | Entire, except eastern North Pacific Ocean--coastal and Bering, Beaufort, and Chukchi Seas | NMFS | E |
| Whale, gray | Eschrichtius robustus | Eastern North Pacific Ocean--coastal and Bering, Beaufort, and Chukchi Seas | NMFS | DM |
| Whale, humpback | Megaptera novaeangliae | - | NMFS | E |
| Whale, killer | Orcinus orca | Southern Resident DPS | NMFS | E |
| Whale, right | Balaena glacialis (incl. australis) | - | NMFS | E |
| Whale, Sei | Balaenoptera borealis | - | NMFS | E |
| Whale, sperm | Physeter catodon (=macrocephalus) | - | NMFS | E |
| Whipbird, western | Psophodes nigrogularis | - | Foreign | E |
| Whipsnake (=striped racer), Alameda | Masticophis lateralis euryxanthus | - | 8 | T |
| Whipsnake, San Joaquin | Masticophis flagellum ruddocki | - | 1 | SC |
| whiptail, Belding's orange-throated | cnemidophorus hyperythrus ssp. beldingi | - | 6 | SC |
| Whiptail, canyon spotted | Cnemidophorus burti | - | 2 | SC |
| Whiptail, coastal western | Cnemidophorus tigris multiscutatus | - | 1 | SC |
| Whiptail, gray-checkered | Cnemidophorus dixoni | - | 2 | SC |
| Whiptail, orange-throated | Cnemidophorus hyperythrus | - | 1 | SC |
| Whirligig, Red Hills unique | Spanglerogyrus albiventris | - | 4 | SC |
| White-eye, bridled | Zosterops conspicillatus conspicillatus | - | 1 | E |
| White-eye, Ghizo | Zosterops luteirostris | - | Foreign | UR |
| White-eye, Norfolk Island | Zosterops albogularis | - | Foreign | E |
| White-eye, Ponape greater | Rukia longirostra | - | Foreign | E |
| White-eye, Rota bridled | Zosterops rotensis | - | 1 | E |
| White-eye, Seychelles | Zosterops modesta | - | Foreign | E |
| White-eye, Truk greater | Rukia ruki | - | Foreign | Unlist |
| White-tailed prairie dog | Cynomys leucurus | - | 6 | RT |
| White-wicky | Kalmia cuneata | - | 4 | SC |
| Whitefish Bear Lake | Prosopium abyssicola | - | 6 | SC |
| Whitefish Bonneville | Prosopium spilonotus | - | 6 | SC |
| whitefish mountain | Prosopium williamsoni | - | 1 | RT |
| whitefish mountain | Prosopium williamsoni | Big Lost River Distinct Population | 1 | RT |
| whitefish, Pygmy | prosopium coulterii | - | 6 | SC |
| Whitlow-grass, Standley | Draba standleyi | - | 2 | SC |
| Whitlow-grass, Stanley | Draba trichocarpa | - | 1 | SC |
| Whitlow-grass, stolon | Draba sobolifera | - | 6 | SC |
| Whitlow-grass, Zion | Draba asprella zionensis | - | 6 | RT |
| Whitlow-grass, [unnamed] | Draba subalpina | - | 6 | RT |
| Whitlow-wort, Ahart's | Paronychia ahartii | - | 1 | SC |
| Whitlow-wort, bushy | Paronychia congesta | - | 2 | RT |
| Whitlow-wort, McCart's | Paronychia maccartii | - | 2 | SC |
| Whitlow-wort, papery | Paronychia chartacea | - | 4 | T |
| Whitlow-wort, Wilkinson's | Paronychia wilkinsonii | - | 2 | SC |
| Whitlow-wort, [unnamed] | Draba exunguiculata | - | 6 | RT |
| Whitlow-wort, [unnamed] | Paronychia rugelii interior | - | 4 | RT |
| wild coffee, Oahu (=kopiko) | Psychotria hexandra ssp. oahuensis var. oahuensis | - | 1 | C |
| Wild indigo, Apalachicola | Baptisia megacarpa | - | 4 | RT |
| Wild indigo, hairy | Baptisia calycosa villosa | - | 4 | SC |
| Wild indigo, [unnamed] | Baptisia riparia | - | 4 | RT |
| Wild pea, Bullfrog Mountain | Lathyrus hitchcockianus | - | 1 | RT |
| Wild-buckwheat, Apache | Eriogonum apachense | - | 2 | SC |
| Wild-buckwheat, Badlands | Eriogonum hylophilum | - | 6 | RT |
| Wild-buckwheat, Brandegee | Eriogonum brandegei | - | 6 | SC |
| Wild-buckwheat, bushy | Eriogonum suffruticosum | - | 2 | SC |
| Wild-buckwheat, Cimarron | Eriogonum aliquantum | - | 2 | RT |
| Wild-buckwheat, clay-loving | Eriogonum pelinophilum | - | 6 | E |
| Wild-buckwheat, Comb Wash | Eriogonum clavellatum | - | 6 | RT |
| Wild-buckwheat, corymbed, Davidse | Eriogonum corymbosum davidsei | - | 6 | RT |
| Wild-buckwheat, corymbed, Reveal | Eriogonum corymbosum revealianum | - | 6 | RT |
| Wild-buckwheat, Cronquist | Eriogonum cronquistii | - | 6 | SC |
| Wild-buckwheat, Darrov's | Eriogonum darrovii | - | 2 | RT |
| Wild-buckwheat, desert | Eriogonum deserticola | - | 1 | RT |
| Wild-buckwheat, dinosaur | Eriogonum lonchophyllum saurinum | - | 6 | RT |
| Wild-buckwheat, Divide | Eriogonum intermontanum | - | 6 | RT |
| Wild-buckwheat, dwarf | Eriogonum nanum | - | 6 | RT |
| Wild-buckwheat, ephedra | Eriogonum ephedroides brevicaule | - | 6 | RT |
| Wild-buckwheat, Fredonia | Eriogonum mortonianum | - | 2 | SC |
| Wild-buckwheat, gypsum | Eriogonum gypsophilum | - | 2 | T |
| Wild-buckwheat, Irion County | Eriogonum nealleyi | - | 2 | RT |
| Wild-buckwheat, lance leaf | Eriogonum lancifolium | - | 6 | RT |
| Wild-buckwheat, limestone | Eriogonum eremicum | - | 6 | RT |
| Wild-buckwheat, Logan | Eriogonum loganum | - | 6 | RT |
| Wild-buckwheat, Matthew's | Eriogonum corymbosum matthewsae | - | 6 | RT |
| Wild-buckwheat, Ostlund | Eriogonum ostlundii | - | 6 | RT |
| Wild-buckwheat, Panguitch | Eriogonum panguicense alpestre | - | 6 | RT |
| Wild-buckwheat, Ripley | Eriogonum ripleyi | - | 2 | SC |
| Wild-buckwheat, San Carlos | Eriogonum capillare | - | 2 | SC |
| Wild-buckwheat, sand-loving | Eriogonum ammophilum | - | 6 | SC |
| Wild-buckwheat, sandstone | Eriogonum jamesii rupicola | - | 6 | RT |
| Wild-buckwheat, Smith | Eriogonum smithii | - | 6 | SC |
| Wild-buckwheat, southern mountain | Eriogonum kennedyi var. austromontanum | - | 8 | T |
| Wild-buckwheat, spreading | Eriogonum lonchophyllum | - | 6 | RT |
| Wild-buckwheat, Thompson | Eriogonum thompsonae thompsonae | - | 6 | RT |
| Wild-buckwheat, Thompson, Atwood's | Eriogonum thompsonae atwoodii | - | 2 | SC |
| Wild-buckwheat, Thompson, white-flow | Eriogonum thompsonae albiflorum | - | 6 | RT |
| Wild-buckwheat, Widstoe | Eriogonum aretioides | - | 6 | SC |
| Wild-buckwheat, Zion, coccineum | Eriogonum zionis coccineum | - | 2 | RT |
| Wild-buckwheat, Zion, zionis | Eriogonum zionis zionis | - | 2 | RT |
| Wild-buckwheat, [unnamed] | Eriogonum ericifolium ericifolium | - | 2 | RT |
| Wild-buckwheat, [unnamed] | Eriogonum flavum aquilinum | - | 7 | SC |
| Wild-quinine, wavyleaf | Parthenium radfordii | - | 4 | SC |
| Wild-rice, Texas | Zizania texana | - | 2 | E |
| Willow, Arizona | Salix arizonica | - | 2 | RT |
| Willow, Florida | Salix floridana | - | 4 | SC |
| Willow, peach-leaved | Salix amygdaloides | - | NA | SU |
| Willow, round-leaf | Salix ovalifolia glacialis | - | 7 | RT |
| Willow, sandbar, inside-outside | Salix interior exterior | - | 5 | RT |
| Willow, [unnamed] | Salix fluviatilis | - | 1 | RT |
| Willowherb, Nevada | Epilobium nevadense | - | 6 | SC |
| Willowherb, Snow Mountain | Epilobium nivium | - | 1 | RT |
| Winged spike | Elliptio nigella | - | 4 | SC |
| Wire-lettuce, Malheur | Stephanomeria malheurensis | - | 1 | E |
| Wire-lettuce, Schott's | Stephanomeria schottii | - | 2 | RT |
| Wireweed | Polygonella basiramia | - | 4 | E |
| Witch-alder, dwarf | Fothergilla gardenii | - | 4 | RT |
| Wolf spider, Lake Placid funnel | Sosippus placidus | - | 4 | SC |
| Wolf, Alexander Archipelago | Canis lupus ligoni | - | 7 | RT |
| Wolf, gray | Canis lupus | Northern Rocky Mountain Gray Wolf Distinct Population Segment; Montana, Wyoming, Idaho, eastern Washington, eastern Oregon, and north central Utah | 6 | DM |
| Wolf, gray | Canis lupus | U.S.A. (MN) | 3 | T |
| Wolf, gray | Canis lupus | U.S.A., conterminous (lower 48) States, except: (1) where listed as an experimental population below; (2) Minnesota; and (3) MT, ID, eastern WA (that portion of WA east of the centerline of Highway 97 and Highway 17 north of Mesa and that portion of WA east of the centerline of Highway 395 south of Mesa),eastern OR (portion of OR east of the centerline of Highway 395 and Highway 78 north of Burns Junction and that portion of OR east of the centerline of Highway 95 south of Burns Junction), and north central UT (that portion of UT east of the centerline of Highway 84 and north of Highway 80). Mexico. | 6 | E |
| Wolf, gray | Canis lupus | U.S.A. (portions of AZ, NM and TX - see section 17.84(k)) | 2 | EXPN |
| Wolf, gray | Canis lupus | Northern Rocky Mtns DPS - WY significant portion of the range | 6 | EXPN |
| Wolf, maned | Chrysocyon brachyurus | - | Foreign | E |
| Wolf, red | Canis rufus | Entire, except where listed as experimental populations below | 4 | E |
| Wolf, red | Canis rufus | U.S.A. (portions of NC and TN_see 17.84(c)(9)) | 4 | EXPN |
| Wolfberry, silver | Lycium puberulum berberioides | - | 2 | RT |
| Wolfberry, Texas | Lycium texanum | - | 2 | SC |
| Wolverine, California | Gulo gulo luteus | - | 1 | SC |
| Wolverine, North American | Gulo gulo luscus | - | 6 | RT |
| Wombat, Queensland hairy-nosed (incl. Barnard's) | Lasiorhinus krefftii (formerly L. barnardi and L. gillespiei) | - | Foreign | E |
| Wood nymph, Carson Valley | Cercyonis pegala carsonensis | Carson Valley | 8 | UR |
| Wood nymph, sthenele | Cercyonis sthenele sthenele | - | 1 | RT |
| Wood nymph, White River | Cercyonis pegala ssp. | White River | 1 | SC |
| Wood snail, Franklin Mountain | Ashmunella pasonis | - | 2 | SC |
| Wood-quail, gorgeted | Odontophorus strophium | - | Foreign | PE |
| Wood-swallow, Palau white-breasted | Artamus leucorhynchus pelewensis | - | Foreign | Unlist |
| Woodland-star, San Clemente Island | Lithophragma maximum | - | 8 | E |
| Woodlandsnail, Cooke's Peak | Ashmunella macromphala | - | 2 | SC |
| Woodlandsnail, Hacheta Grande | Ashmunella hebardi | - | 2 | SC |
| woodpecker, Black-backed | picoides arcticus | - | 7 | SC |
| woodpecker, Downy | picoides pubescens | - | 7 | SC |
| woodpecker, Gila | melanerpes uropygialis | - | 6 | SC |
| Woodpecker, helmeted | Dryocopus galeatus | - | Foreign | UR |
| Woodpecker, imperial | Campephilus imperialis | - | Foreign | E |
| Woodpecker, ivory-billed | Campephilus principalis | entire | 4 | E |
| Woodpecker, Okinawa | Dendrocopus noguchii | - | Foreign | UR |
| woodpecker, Pileated | dryocopus pileatus | - | 6 | SC |
| Woodpecker, red-cockaded | Picoides borealis | - | 4 | E |
| woodpecker, Three-toed | picoides tridactylus | - | 6 | SC |
| Woodpecker, Tristam's | Dryocopus javensis richardsi | - | Foreign | E |
| Woodrat, Alleghany | Neotoma magister | - | 5 | UR |
| Woodrat, Key Largo | Neotoma floridana smalli | - | 4 | E |
| Woodrat, Monterey dusky-footed | Neotoma fuscipes luciana | - | 1 | SC |
| Woodrat, riparian (=San Joaquin Valley) | Neotoma fuscipes riparia | - | 8 | E |
| Woodrat, San Diego desert | Neotoma lepida intermedia | - | 1 | SC |
| Woodrat, San Francisco dusky-footed | Neotoma fuscipes annectens | - | 1 | SC |
| Woodrat, Santa Catalina Mountains | Neotoma mexicana bullata | - | 2 | SC |
| Woodrat, Southern Appalachian eastern | Neotoma floridana haematoreia | - | 4 | SC |
| Woodrat, White Sands | Neotoma micropus leucophaea | - | 2 | SC |
| Woodsia, Oregon | Woodsia oregana cathcartiana | - | 3 | SC |
| Woodstar, Chilean | Eulidia yarrellii | - | Foreign | PE |
| Woodstar, Esmeraldas | Chaetocercus berlepschi | - | Foreign | PE |
| Woolly-star, Hoover's | Eriastrum hooveri | - | 8 | DP |
| Woolly-star, Santa Ana River | Eriastrum densifolium ssp. sanctorum | - | 8 | E |
| Wooly-pod, Bear Valley | Astragalus leucolobus | - | 1 | SC |
| Wooly-pod, black | Astragalus funereus | - | 1 | SC |
| Wooly-sunflower, Barstow | Eriophyllum mohavense | - | 1 | SC |
| Wooly-sunflower, Congdon's | Eriophyllum congdonii | - | 1 | RT |
| Wooly-sunflower, Ft. Tejon | Eriophyllum lanatum hallii | - | 1 | SC |
| Wooly-sunflower, Nevin's | Eriophyllum nevinii | - | 1 | SC |
| Wooly-sunflower, Yosemite | Eriophyllum nubigenum | - | 1 | SC |
| Wooly-threads, San Joaquin | Monolopia (=Lembertia) congdonii | - | 8 | E |
| Wormwood, Aleutian | Artemisia aleutica | - | 7 | RT |
| Wormwood, Northern | Artemisia campestris var. wormskioldii | - | 1 | C |
| Wormwood, [unnamed] | Artemisia globularia lutea | - | 7 | SC |
| Wormwood, [unnamed] | Artemisia glomerata subglabra | - | 7 | SC |
| Woundfin | Plagopterus argentissimus | Entire, except Gila R. drainage, AZ, NM | 6 | E |
| Woundfin | Plagopterus argentissimus | Gila R. drainage, AZ, NM | 6 | EXPN |
| Wren, Appalachian Bewick's | Thryomanes bewickii altus | - | 5 | SC |
| Wren, Cactus | Campylorhynchus brunneicapillus | - | 1 | SC |
| Wren, Guadeloupe house | Troglodytes aedon guadeloupensis | - | Foreign | E |
| Wren, Niceforo's | Thryothorus nicefori | - | NA | SU |
| Wren, San Clemente Bewick's | Thryomanes bewickii leucophrys | - | 1 | RT |
| Wren, San Diego cactus | Campylorhynchus brunneicapillus couesi | - | 1 | RT |
| Wren, St. Lucia house | Troglodytes aedon mesoleucus | - | Foreign | E |
| Xyris, karst pond | Xyris longisepala | - | 4 | SC |
| Yak, wild | Bos mutus (=grunniens m.) | - | Foreign | E |
| Yampah, adobe | Perideridia pringlei | - | 1 | RT |
| Yampah, Gairdner's | Perideridia gairdneri gairdneri | - | 1 | SC |
| Yampah, Mother Lode | Perideridia bacigalupii | - | 1 | RT |
| Yampah, narrow-seeded | Perideridia leptocarpa | - | 1 | RT |
| Yampah, red-root | Perideridia erythrorhiza | - | 1 | SC |
| Yellow-cress, Columbia | Rorippa columbiae | - | 1 | UR |
| Yellow-eyed grass, Drummond's | Xyris drummondii | - | 4 | SC |
| Yellow-faced bee, andrenoid | Hylaeus andrenoides | - | 1 | SC |
| Yellow-faced bee, anomalous | Hylaeus anomala | - | 1 | SC |
| Yellow-faced bee, anthricinan | Hylaeus anthracinus | - | 1 | UR |
| Yellow-faced bee, assimulans | Hylaeus assimulans | - | 1 | UR |
| Yellow-faced bee, Blackburn's | Hylaeus blackburni | - | 1 | RT |
| Yellow-faced bee, bluewing | Hylaeus caeruleipennis | - | 1 | SC |
| Yellow-faced bee, bristlefront | Nesoprosopis setosifrons | - | 1 | RT |
| Yellow-faced bee, broadhead | Hylaeus laticeps | - | 1 | RT |
| Yellow-faced bee, chlorostictan | Hylaeus chlorosticata | - | 1 | SC |
| Yellow-faced bee, comes | Hylaeus comes | - | 1 | SC |
| Yellow-faced bee, conehead | Hylaeus coniceps | - | 1 | SC |
| Yellow-faced bee, connected | Hylaeus connectens | - | 1 | RT |
| Yellow-faced bee, crabronoid | Hylaeus crabronoides | - | 1 | SC |
| Yellow-faced bee, darkwing | Hylaeus fuscipennis | - | 1 | SC |
| Yellow-faced bee, difficult | Hylaeus difficilis | - | 1 | SC |
| Yellow-faced bee, dimidiatan | Hylaeus dimidiata | - | 1 | SC |
| Yellow-faced bee, easy | Hylaeus facilis | - | 1 | UR |
| Yellow-faced bee, erythrodeme | Hylaeus erythrodemas | - | 1 | RT |
| Yellow-faced bee, Fern | Hylaeus filicum | - | 1 | SC |
| Yellow-faced bee, finitiman | Hylaeus finitima | - | 1 | RT |
| Yellow-faced bee, furry | Hylaeus pubescens | - | 1 | SC |
| Yellow-faced bee, Haleakala | Hylaeus haleakalae | - | 1 | SC |
| yellow-faced bee, Hawaiian | Hylaeus kuakea | - | 1 | UR |
| yellow-faced bee, Hawaiian | Hylaeus mana | - | 1 | UR |
| Yellow-faced bee, hilaris | Hylaeus hilaris | - | 1 | UR |
| Yellow-faced bee, hirsute | Hylaeus hirsutula | - | 1 | SC |
| Yellow-faced bee, hostile | Hylaeus hostilis | - | 1 | SC |
| Yellow-faced bee, hulan | Hylaeus hula | - | 1 | SC |
| Yellow-faced bee, insignis | Hylaeus insignis | - | 1 | SC |
| Yellow-faced bee, Kauai | Hylaeus kauaiensis | - | 1 | SC |
| Yellow-faced bee, Koa | Hylaeus koae | - | 1 | SC |
| Yellow-faced bee, Kona | Hylaeus kona | - | 1 | SC |
| Yellow-faced bee, Laetan | Hylaeus laeta | - | 1 | SC |
| Yellow-faced bee, Lanai | Hylaeus angustula | - | 1 | RT |
| Yellow-faced bee, longhead | Hylaeus longiceps | - | 1 | UR |
| Yellow-faced bee, Maui | Nesoprosopis mauiensis | - | 1 | RT |
| Yellow-faced bee, melanothrix | Nesoprosopis melanothrix | - | 1 | RT |
| Yellow-faced bee, Molokai | Nesoprosopis neglecta | - | 1 | RT |
| Yellow-faced bee, monocolor | Nesoprosopis homeochroma | - | 1 | RT |
| Yellow-faced bee, mutatan | Nesoprosopis mutata | - | 1 | RT |
| Yellow-faced bee, obscuratan | Hylaeus obscurata | - | 1 | SC |
| Yellow-faced bee, Ombrias | Hylaeus ombrias | - | 1 | SC |
| Yellow-faced bee, pele | Nesoprosopis pele | - | 1 | RT |
| Yellow-faced bee, Perkin's | Hylaeus perkinsiana | - | 1 | SC |
| Yellow-faced bee, perspicuan | Hylaeus perspicua | - | 1 | RT |
| Yellow-faced bee, psammobian | Hylaeus psammobia | - | 1 | RT |
| Yellow-faced bee, rugulose | Nesoprosopis rugulosa | - | 1 | RT |
| Yellow-faced bee, satellus | Hylaeus satellus | - | 1 | SC |
| Yellow-faced bee, simple | Hylaeus simplex | - | 1 | SC |
| Yellow-faced bee, snowy | Nesoprosopis nivalis | - | 1 | RT |
| Yellow-faced bee, specular | Hylaeus specularis | - | 1 | SC |
| Yellow-faced bee, sphecodoid | Hylaeus sphecodoides | - | 1 | SC |
| Yellow-faced bee, unique | Hylaeus unica | - | 1 | SC |
| Yellow-faced bee, very | Hylaeus flavifrons | - | 1 | SC |
| Yellow-faced bee, vicinan | Hylaeus vicina | - | 1 | SC |
| Yellow-faced bee, volatile | Hylaeus volatilis | - | 1 | SC |
| Yellow-faced bee, yellow-foot | Hylaeus flavipes | - | 1 | SC |
| Yellowhead, desert | Yermo xanthocephalus | - | 6 | T |
| Yellowshow, Wright's | Amoreuxia wrightii | - | 2 | RT |
| Yellowthroat, Brownsville common | Geothlypis trichas insperata | - | 2 | SC |
| Yellowthroat, saltmarsh common | Geothlypis trichas sinuosa | - | 1 | SC |
| Yerba de zanja | Ruppia anomala | - | 4 | RT |
| Yerba santa, Lompoc | Eriodictyon capitatum | - | 8 | E |
| Yew, Florida | Taxus floridana | - | 4 | SC |
| Yew, Pacific | Taxus brevifolla | - | NA | RT |
| Zarzarilla | Schrankia portoricensis | - | 4 | SC |
| Zebra, Grevy's | Equus grevyi | - | Foreign | T |
| Zebra, Hartmann's mountain | Equus zebra hartmannae | - | Foreign | T |
| Zebra, mountain | Equus zebra zebra | - | Foreign | E |
| Ziziphus, Florida | Ziziphus celata | - | 4 | E |
| Zoroapteran, Swezey's | Zorotypus swezeyi | - | 1 | SC |
| `Ahakea | Bobea sandwicensis | - | 1 | RT |
| `Ahakea | Bobea timonioides | - | 1 | SC |
| `Ahinahina | Argyroxiphium sandwicense ssp. macrocephalum | - | 1 | T |
| `Ahinahina | Argyroxiphium sandwicense ssp. sandwicense | - | 1 | E |
| `Aiakeakua, popolo | Solanum sandwicense | - | 1 | E |
| `Aiea | Nothocestrum breviflorum | - | 1 | E |
| `Aiea | Nothocestrum latifolium | - | 1 | C |
| `Aiea | Nothocestrum longifolium rufipilosum | - | 1 | RT |
| `Aiea | Nothocestrum peltatum | - | 1 | E |
| `Akoko | Chamaesyce arnottiana | - | 1 | SC |
| `Akoko | Chamaesyce atrococca | - | 1 | SC |
| `Akoko | Chamaesyce celastroides tomentella | - | 1 | SC |
| `Akoko | Chamaesyce celastroides var. kaenana | - | 1 | E |
| `Akoko | Chamaesyce deppeana | - | 1 | E |
| `Akoko | Chamaesyce eleanoriae | - | 1 | E |
| `Akoko | Chamaesyce herbstii | - | 1 | E |
| `Akoko | Chamaesyce kuwaleana | - | 1 | E |
| `Akoko | Chamaesyce olowaluana | - | 1 | SC |
| `Akoko | Chamaesyce remyi hanaleiensis | - | 1 | RT |
| `Akoko | Chamaesyce remyi var. kauaiensis | - | 1 | E |
| `Akoko | Chamaesyce remyi var. remyi | - | 1 | E |
| `Akoko | Chamaesyce rockii | - | 1 | E |
| `Akoko | Chamaesyce skottsbergii vaccinioides | - | 1 | SC |
| `Akoko | Chamaesyce sparsiflora | - | 1 | SC |
| `Akoko | Euphorbia haeleeleana | - | 1 | E |
| `Akoko, Ewa Plains | Chamaesyce skottsbergii var. kalaeloana | - | 1 | E |
| `aku | Cyanea tritomantha | - | 1 | C |
| `Ala `ala wai nui | Peperomia subpetiolata | - | 1 | C |
| `Anaunau | Lepidium arbuscula | - | 1 | E |
| `Anaunau | Lepidium bidentatum o-waihiense | - | 1 | RT |
| `Anaunau | Lepidium serra | - | 1 | SC |
| `Anaunau, Remy's | Lepidium bidentatum remyi | - | 1 | SC |
| `Anunu | Sicyos alba | - | 1 | E |
| `Anunu | Sicyos cucumerinus | - | 1 | SC |
| `Anunu | Sicyos macrophyllus | - | 1 | C |
| `Awikiwiki | Canavalia molokaiensis | - | 1 | E |
| `Awikiwiki | Canavalia napaliensis | - | 1 | E |
| `Awikiwiki | Canavalia pubescens | - | 1 | C |
| `Ena`ena | Pseudognaphalium (=Gnaphalium) sandwicensium var. molokaiense | - | 1 | C |
| `Ena`ena, whip | Gnaphalium sandwicensium flagellare | - | 1 | RT |
| `Ilihia | Cyrtandra begoniifolia | - | 1 | RT |
| `Oha wai | Clermontia drepanomorpha | - | 1 | E |
| `Oha wai | Clermontia lindseyana | - | 1 | E |
| `Oha wai | Clermontia oblongifolia ssp. brevipes | - | 1 | E |
| `Oha wai | Clermontia oblongifolia ssp. mauiensis | - | 1 | E |
| `Oha wai | Clermontia peleana | - | 1 | E |
| `Oha wai | Clermontia pyrularia | - | 1 | E |
| `Oha wai | Clermontia samuelii | - | 1 | E |
| `Ohe | Joinvillea ascendens ascendens | - | 1 | C |
| `Ohe | Reynoldsia sandwicensis | - | 1 | RT |
| `Ohe | Tetraplasandra hawaiiensis microcarpa | - | 1 | RT |
| `Ohe | Tetraplasandra kaalae multiplex | - | 1 | RT |
| `Ohe`ohe | Tetraplasandra gymnocarpa | - | 1 | E |
| `Ohe`ohe | Tetraplasandra kavaiensis grandis | - | 1 | RT |
| `Ohe`ohe | Tetraplasandra kavaiensis koloana | - | 1 | RT |
| `Ohe`ohe | Tetraplasandra kavaiensis occidua | - | 1 | RT |
| `Ohe`ohe ) | Tetraplasandra kavaiensis dipyrena | - | 1 | RT |
| `Ohe`ohe e | Tetraplasandra kavaiensis intercedens | - | 1 | RT |
| `Ohe`ohe s | Tetraplasandra kavaiensis nahikuensis | - | 1 | RT |
| `O`o, Bishop's | Moho bishopi | - | 1 | SC |
| `O`o, Kauai (honeyeater) | Moho braccatus | - | 1 | E |
| `O`u (honeycreeper) | Psittirostra psittacea | - | 1 | E |
Last updated: June 28, 2010
