Diversity of freshwater mollusc in the Western Ghats
N.A. Aravind* and N.A. Madhyastha** Suri Sehgal Centre for Conservation Science, Ashoka Tru st for Research in Ecology and the Env ironment (ATREE), Bangalore- 560024. **Malacology Centre, Poorna Prajna College, Udupi- 576101. DIVERSITY OF FRESHWATER MACROINVERTEBRATES HABITAT DIVERSITY OF FRESHWATER ECOSYSTEMS
PONDS LAKES
STREAMS AND RIVERS BACKWATERS AND ESTUARIES FRESHWATER BIODIVERSITY HOTSPOTS OF THE WORLD
The Western Ghats is a hotspot for freshwater fishes, crabs and Mollusks Estimated numbers of described and undescribed terrestrial and freshwater mollusc
70000
Max Undescribed 60000 Described y t ii 50000
40000 ecies)
ollusc divers Min pp mm 30000
onmarine Max Number of s 20000 NN ((
Min 10000
0 Terrestrial Freshwater
Source: Lydeard et al. 2004 Taxonomic break up of Indian freshwater mollusc fauna
Gastropods Bivalves Total Western Ghats Families 12 09 21 13 Genus 36 21 57 20 Species 170 113 214 60
Source: Subba Rao 1989 and Shivaramakrishnan et al. 1999 Cremnochonchus sahydarensis Lithtotis rupicola
Arsidopsis footi
Arsidopsis sp, Pseudomulleria dalyii
Cremnochonchus sp
Paracrostoma tigrina, Paracrostoma martini Habitat preference of freshwater molluscs of the Western Ghats
Rivers and stream are species rich habitats
Habitat distribution of Freshwater molluscs Arsidopsis footi Pseudomulleria dalyi
70
60
50
ices 40
30
Percent spe Percent 20
10
0 Lentic Lotic Both
Habitat Zoo-geographically interesting species in the Western Ghats
Marine elements in the freshwater mollusc fauna of the Western Ghats
Neritinea perottetiana (Neritidae)
Cremnoconchus syhadrensis (Litterorinidae) Zoo-geographical significance of Western Ghats molluscan fauna
Cremnochonchus
Pseudomulleria
Paracrostoma Cremnochonchus sp.
• Member of marine family • Shows that Part of the Western Ghats was under the sea • Highly specialsed habitat- waterfalls • Only on the western slopes Zoo-geographically interesting species in the Western Ghats
Family: Genus: Species: South America, Etheriidae 3 3 Madagascar, Tropical Africa and India
A Gondwana relict, cemented bivalve of the Western Ghats
Pseudomulleria dalyii
Only Five populations of <2000 individuals Family Etheridae- An Gon dwana lan d re litlict
Pseudomulleria
Western Ghats
Acostea Etheria
Africa and Madagascar Colombia … Into India Adamietta
Brotia
Adamietta Brotia
Paracrostoma
Adamietta “…origg(ins of the Indian biota (freshwater mollusc) are more complex and diverse than assumed under the standard Mesozoic vicariance model…”
Kohler and Glaubrecht 2007 Importance
• Food: – For humans: Clams, Pila, Thiara etc – Animals • Nutrient cycling: In Terrestrial and Freshwater • Indicator of ecosystem health-Bioindicators • Agricultural pests • Invasive Threats THREAT STATUS OF RIVER CATCHMENTS OF THE WORLD
River catchments of peninsular India is most threatened Pollution Bivalves Gastropods
Bivalves Gastropods Dams
Bivalves Gastropods Mines
Agriculture Bivalves Gastropods
Urbanization Bivalves Gastropods Percentage of extinct animals in different faunal groups
Amphibians CtCrustaceans 1% 1% Others Reptiles 0% 3% Insects 10%
Mammals Mollusca 11% 43%
Fishes 12% Birds
Source: www.redlist.org. Total number of threatened species of mollusc
1400 1222 1200
1000
800 708 ecies pp 600 # s 429 400
200 41 0 TrrtrilTerrestrial Fresh wat er MrinMarine LtCnrnLeast Concern Group
Source: www.redlist.org. India and Western Ghats???
OlOnly ONE has b een li st ed und er IUCN red list category
Pseudomulleria dalyii The big challenge of freshwater biodiversity Conservation- Environmental water demand and social requirement Significant wetlands of the wwesternestern ghatsghats aandnd theirtheir conservation status GODAVARI CATCHMENT
Wetland Nos./Region/ PROTECTION Habitats Locality KRISHNA Rivers 3 large, 13 3 River CATCHMENT medium and 17 Sanctuaries minor (Fish) Backwaters Ashamudi, 2 Ramsar sites Kuttanad, Vembanad, Kole wetlands CAUVERY (Kerala) CATCHMENT Estuaries/ Bharatapuzha, Nil Mangroves Netravathi, Gurupura, Gangolli, Sharavathi, Aghanasini, Kali, Mandovi A Gap Analysis ¾ No comprehensive assessment of freshwater biodiversityyg of the region
¾ FtFew taxonomi itdifhtc studies on freshwater moll uscs
¾ Little information available on the distribution and ecology of the most of the s pecies
¾ Few studies on the river ecology and its interaction with other species Acknowledgements
Dept. of Science and Technology
Endemics Current Threats (Contd..)
DAMS MINES
MINES AGRICULTURE EXPANSION Current Threats
RIPARIAN DEFORESTATION WASTE DISPOSAL
INFRASTRUCTURE DEVELOPMENT INDUSTRIAL POLLUTION Endemism and habitat preference of freshwater molluscs of The Western Ghats
Rivers and stream are species rich habitats.
Habitat distribution of Freshwater molluscs Arsidopsis footi Pseudomulleria dalyi
70
60
50
ices 40
30
Percent spe Percent 20
10
0 Lentic Lotic Both
Habitat