Ethnobotanical Leaflets 12:
108-117. 2008. How to
Identify Rare and Endangered Ferns and Fern Allies A. Benniamin, V. Irudayaraj*
and V. S. Manickam *Department of
Plant Biology and Biotechnology, Centre for Biodiversity and
Biotechnology, St. Xavier’s College
(Autonomous), Palayamkottai, Tamil
Nadu, India – 627 002 e- mail: fernsbenni@yahoo.co.in Issued ABSTRACT Identification
of rare and endangered plant species is the first requirement for any conservation
programme. The IUCN guideline is the only available method to identify the
rare and endangered species and it requires vast data on the wild population
of the target species. None of the biological characters, which are playing
main role in the survival and distribution of several species, is used in
IUCN guideline. In the meantime there are several difficulties in following
IUCN guideline, particularly the non availability of complete field data.
Moreover, the same guideline can not be used for all the groups of species in
equal importance. The vascular cryptogams, pteridophytes, are also an
important component of any mountainous flora and they have also to be
conserved in nature. As they are the primitive vascular plants on the earth,
they are getting depleted in the flora due to various reasons and it is the
right time to identify the rare and endangered pteridophytes to conserve
them. By considering various difficulties of IUCN method for the
identification rare and endangered pteridophytes, a very simple method has
been adopted by using just four criteria and this method can be applied to
Pteridophytes from any region of the world. Keywords: Conservation, Rare and Endangered ferns,
Identification. “Ferns in art convey the idea of solitary humility,
frankness and sincerity, because they conceal their grace and beauty in forest depth” INTRODUCTION Plants are the foundation of all life on
earth, without which we cannot survive.
IUCN Red List shows the number of
threatened vascular plant species recorded for each country. A high figure of threatened species for a
particular country, like 29% in According to IUCN Red List, out of 511
families of vascular plants currently recognized, 372 of these contain
globally threatened and /or extinct species.
Not surprisingly, the largest families also contain the largest
numbers of threatened species.
Excluding nineteen threatened monotypic families (only one species in
the family, and thus 100 percent threatened), there are 20 plant families with
at least 50 percent of their species threatened. Of these, eight are gymnosperm families
(including cycads and conifers). The
prominence of gymnosperms may be due to one or more factors: 1. They are a
well known and relatively small group; 2. Many gymnosperm species are widely
exploited both for timber and horticultural purposes; 3. Gymnosperms are an
ancient group of species, and may not adapt easily to the rapidly changing
environment around them. In contrast,
the ferns as a group appear to face relatively low levels of threat. This may be due in part to the efficiency
with which fern spores are dispersed.
At the same time, fern species have not been fully assessed, so their
status as a group is not entirely clear.
With this background it was planned to assess the Indian Pteridophytes,
by selecting the Pteridophytes of the METHODOLOGY Several
methods, including the typical method adopted by IUCN, were tried to identify
the rare and endangered Pteridophytes of the For the successful establishment of a plant
species in an ecosystem, the species should reproduce successfully through
vegetative or sexual method by producing fertile and viable seeds /
spores. It needs specific and suitable
ecological niche to establish itself successfully. In the meantime they should have the
capacity to colonise a particular ecological niche easily and in general they
should have good genetical make up. As
far as ferns are concerned the species with erect rhizome could not colonise
a place easily when compared to the species with creeping rhizome. In general polyploid species are more
tolerable than the diploid species. In
evolution polyploidization is usually accomplished with the property of
vegetative reproduction ( RESULT With this context the key factors,
particularly biological factors, such as rhizome type (erect or creeping),
ploidy level (diploid or polyploid), nature of the spores (chlorophyllous or
achlorophyllous) and ecological factor such as habitats, (epiphyte /
lithophyte or terrestrial), responsible for the rarity of ferns and fern
allies were identified and applied for the assessment of rare and
endangered ferns and fern allies of
the Western Ghats along with other criteria followed by Perring and Farrell (
1977). As far as ferns are concerned
each and every species will score equally when we give the threat value for
each criterion mentioned by Perring and Farrell like economical value,
accessibility of the species etc.
Because all the ferns are having at least some economical values and
most of the ferns are growing in forest interior and it is very difficult for
access. So it is very difficult to
differentiate a rare and common fern when they score more or less same range
of threat values. The application of
the above biological criteria gave meaningful results and when they are
applied separately they give more or less the same kind of results. So, for the present analysis only these
criteria were used (Fig.1). It is a
very simple method based on only five criteria and the successfulness of this
method has also been tested for ferns from other geographical regions
(Himalayas) and it seems to be a natural, successful, easy method to test and
locate a fern or fern ally in the red list category. The list of rare and endangered ferns of
the Western Ghats, identified by following this method, is given here
(Table.1) The validity of the present method has also
been tested with the Himalayan ferns. In the first volume of “An Illustrated
Flora of Western Himalaya” by Khullar (1994) totally 190 species of
ferns have been described along with information on cytology, distribution
and ecology. By applying the present method, all the 190 species have been
categorized into different ranks. Thus the number of species belonging to
each rank in the order of first rank to the last rank has been given in table
2. Manickam (1995) has also enumerated 46 rare and endangered ferns of the
Western Ghats of South India, based on his own field experience for about
thirty years. The species included in that list has also come under any one
of the threat category of the present study and thus it is of more value. But
the problem is those who want to identify a rare and endangered species for
conservation purpose, he may not have such a kind of experience and he has to
depend on either the ready made list or the scientific method to identify
such species easily. Few examples may be cited to test the
validity of the present method. The diploid fern Grammitis medialis
with erect rhizome, chlorophyllous spores and epiphyte/ lithophyte habitat
belonging to the first category has been recorded from only two localities
from the Western Ghats. The diploid
or tetraploid lithophytic fern Hypodematium crenatum with
prostrate rhizome and achlorophyllous spores belonging to the first category
has been recorded from only three distinct localitites from the Western Ghats
(Manickam & Irudayaraj 1992). In contrast, the tetraploid, terrestrial
fern Christella parasitica with short or long-creeping rhizome,
achlorophyllous spores belonging to the last category is the most common fern
in South India. It is commonly growing throughout the Western Ghats (Manickam
& Irudayaraj 1992). In the same way, the tetraploid,
terrestrial bracken fern, Pteridium aquilinum with long creeping
rhizome and achlorophyllous spores belongs to the last category. Thus it is
common colonizer in forest clearings throughout the Western Ghats (Manickam
& Irudayaraj 1992) The diploid epiphytic fern Ctenopteris subfalcata
with sub-erect rhizome and chlorophyllous spores belonging to the first
category has been recorded from only two localities from the Western
Himalayas (Khullar 1997). The lithophytic fern, Woodsia andersonii
with erect rhizome and chlorophyllous spores belonging to the first category
is a very rare fern known only from the Western Himalayas. The tetraploid
terrestrial fern Deparia petersenii with creeping rhizome,
achlorophyllous spores belonging to the last category is a common fern
throughout the Western Himalayas. (Khullar 1997) The advantage of the present method is not
only the easy one but also a more accurate method to choose the species for
conservation among closely related species. On the other hand there are some
minor problems which may be solved by taking little more scientific efforts.
For example, cytological data may not be available for some species. This can
be done if fresh specimens are available. In the present study chromosome
number (n= 80 ) for Tectaria zeilanica
has been reported for the first time from India ( Fig 3-d )In those cases of
species, where only herbarium specimens are available, the ploidy level may
be determined based on the size of the spores and (or) stomatal guard cell in
comparison with the other related species. The presence of more than one
cytotype within a species will result in little more problems to consider the
species as a whole or as a diploid one or polyploid one. In such cases the priority should be given
to the diploid cytotype of the species. SUGGESTION
OF METHODS FOR CONSERVATION As in any conservation strategies, in the
cases of ferns also, the best method of conserving the species is by in
situ conservation by protecting the natural habitats particularly in ever
green forests where they grow commonly.
Some cases may require ex situ conservation either by
multiplying species by conventional method or by in vitro tissue
culture or spore culture method. Such
multiplied species may be conserved in the garden. As far as The purpose of the present paper is to
expose the rare and endangered ferns to the conservationists who are
interested in conserving the rare and endangered ferns through in vitro
tissue culture or spore culture.
Usually they choose the species, for such conservation measures,
without making serious efforts to identify the rare and endangered
ferns. Some times they wrongly choose
some of the common species even with the availability of the rare
species. In Table 1: List of endangered taxa from the
Western Ghats (Fig. 2 & 3) 1. Adiantum lomesam Nayar & Geevar. 2. Alsophilla nilgirensisHolttum var.lobatus Manick. & Irud. 3. Ampelopteris prolifera (Retz.) Copel. 4. Anemia wightiana Gard. 5.
Anisocampium cumingianum Presl. 6. Asplenium
affine Sw. 7. Athyrium solenopteris var pusillum (Kunze) 8. Cheilanthes rufa D.Don. 9. Ctenopteris subfalcata (Bl.) Kunze. 10. Dicranopteris taiwanensis Ching et Chiou 11. Dryopteris approximata Sledge 12. Grammitis attenuata Kze. 13. Grammitis medialis (Baker.) Sledge 14. Helminthostachys zeylanica (L.)Hook. 15. Huperzia hamiltonii (Spring)Trev. 16. Huperzia hilliana (Nessel) Holub. 17. Huperzia
squarrosa (G.Forst.) Trev. 18.
Hypodematium crenatum (Forssk.)Kuhn 19. Lindsaea
malabarica (Bedd.)Bak. 20.
Lycopodium japonicum Thunb. 21.
Phanerophlebia caryotidea var. caryotidea
(Wall.ex.Hook & Grev.) Copel. 22. Phymatosorus
malabaricus (Nayar & Geevar.) Geevar.ex Nampy ex
Madhus. 23.
Polystichum subinerme (Kze.) Fras. –Jenk. 24. Polystichum tacticopterum (Kunze) T.Moore 25. Prosaptia obliquata (Bl.)Mett. 26. Pteris wallichiana Agardh. 27.
Selaginella microdendron Bak. 28. Tectaria
periya Nayar & Geevar. 29. Tectaria zeilanica (Holtt.) Sledge. 30. Trichomanes vamana Hameed & Madhus. Table : 2 List of Endangered
taxa from 1.
A. bullatum Wall. ex Mett. 2.
A. lingtaulensis Ching 3.
A. nesii Christ. 4.
A. tenuicaule Hayata. 5.
A. tenuifolium D.Don. 6.
A. wallichiana (Spreng.) Ching 7.
Adiantum
edgeworthii Hooker. 8.
Arthromeris
lehmanii (Mett.) Ching. 9.
Asplenium
anogrammoides Christ. 10.
Botrychium lanuginosum (L.) Swartz. var. onondagense (underwood) House 11.
B. multifidum (Gmelin) Ruprecht. 12.
B. ternatum (Thunb.) Swartz. 13.
B. lunaria
(L.) Swartz. 14.
Cheilanthes dubia
Hope. 15.
C. duthiei Baker. 16.
C. persica (Bory) Mett. ex Kuhn. 17.
C. chrysophylla Hooker. 18.
C. anceps Blanford. 19.
Colysis
pothifolia (Ham. ex D. Don) H. Ito. 20.
Cryptogramma brunoniana Wall. ex
Hooker et Greville. 21.
Dennstaedtia
wilfordii ( 22.
D. scabra Wall. ex 23.
Dicranopteris
linearis var. subferruginea (Hieron.)
Nakai. 24.
Drynaria tibetica Ching et Wu. 25.
Lepisorus
clathratus (Clarke) Ching. 26.
L. contortus (Christ) Ching. 27.
L. oligolepidus (Baker) Ching. 28.
L. bicolor Ching 29.
Loxogramme
parallela Copel. 30.
Osmunda japonica
Thunb. 31.
O. regalis L. 32.
O. claytoniana L. 33.
Pellea
subfurfuracea (Hooker) Ching. 34.
P. hastata (Thunb.) Prantl. 35.
Phymatopteris
erythrocarpa (Mett. ex Kuhn) Pichi -Sermolli 36.
Pteris
wallichiana Agardh 37. Pyrrosia costata (Wall. ex Presl) Tagawa et Iwatsuki. 38.
Woodsia
andersonii (Beddome) Christ ACKNOWLEDGEMENTS
Authors are thankful to Rev. Dr. A.
Antonysamy S.J., the Principal, St. Xavier’s College, Palayamcottai for his encouragements.
Dr. A. Benniamin is thankful to the financial assistance received from the
Department of Science and Technology Government of India, through the Young
Scientist award. REFERENCES Theuerkauf, W.D. 1994 Preserving south Indian Pteridophytes. J. Archives. Vol. 2(3). 4-8. Bakgh – Comeau.Y. S. 1999 Risk
indexing rating of threatened ferns in Zajac. A and
Zajac. 1995 Eds., Distribution Atlas of Vascular plants in Irudayaraj,V. Manickam,V.S. and Johnson, M. 2003.
Vivipary, a rare and evolutionary important phenomenon in a rare homosporous
fern Grammitis medialis from the Perring, F.H. and Farrell,L. 1977. British Red data Books: Vascular
plants, Khullar S.P. 1994. An illustrated Fern flora of Western
Himalaya Vol. 1 & II International Book Distributors, Dehradun. Manickam V.S. 1995 Rare and endangered ferns of the Western
Ghats of South India, Fern Gaz.
15:1- 10. Manickam V.S and Irudayaraj V. 1992 Pteridophyte flora of
Western Ghats of South India. B.I.Publication, Khare P.B. Raza F. and Kaur S.
1989 Propagation of fern through spores Ind. Fern. Jl. 6: 247 -250 Fig. 1. Key for the
identification of rare and endangered ferns and fern allies
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