Leptodoridae
Large (>8mm) with a segmented tail
Leptodora kintii

 

Cercopagidae
6-8mm with spiny tails making up >3/4 of this length
Cercopagis pengoi and Bythotrephes longiramus

Holopedidae
0.55-2.2mm with an incomplete carapace, a gelatinous sheath and a short true tail
Holopedium gibberum

Polyphemoidea
0.8-2.0mm with an incomplete carapace and a long true tail
Polyphemus pediculus

Daphnidae
inconspicuous 1st antennae, <10 setae on the dorsal branch of the 2nd antennae, may have a rostrum but not an extended beak
18 Great Lakes species in 4 genera

Sididae
>14 setae on the dorsal branch of the 2nd antennae
5 Great Lakes species in 4 genera

Macrothricidae
Long 1st antennae attached at the front of the head
8 Great Lakes species in 6 genera

Moinidae
0.5-0.6mm Long, flexible, conspicuous first antennae and large (1/3 length) head
Moina micrura

Chydoridae
1st antennae covered by a beak
32 Great Lakes species in 15 genera

Bosminidae
Tusklike 1st antennae
Bosmina longirostris and Eubosmina coregoni