Faunal diversity of Cladocera (Crustacea: Branchiopoda) with notes on biogeographically important species in the floodplain wetlands of the Subansiri River basin, India

The plankton samples collected from the Subansiri floodplain wetlands revealed a rich Cladocera assemblage of 55 species belonging to 30 genera and 7 families. The species richness represents 42% and 75% of the total amount of fresh water species reported from India and Assam, respectively. Chydoridae was the most speciose family, with 31 species, while Ilyocryptidae was represented by a single species. Sididae, Daphniidae, Bosminidae, Moinidae and Macrothricidae were represented by four, five, three, two and four species, respectively. The faunal composition is represented by cosmopolitan, tropical and oriental elements. The documentation of Diaphanosoma dubium, Latonopsis australis, Simocephalus mixtus, Chydorus sphaericus, Chydorus parvus, Chydorus ovalis, Alonella clathratula, Pleuroxus cf. denticulatus, Picripleuroxus quasidenticulatus, Celsinotum macronyx, Corona tella anodonta and Kurzia (Rostrukurzia) brevilabris has biogeographic importance. We provide brief geographical distributional remarks about these 12 species from the collected samples. This was a preliminary study, as the fauna from the Indian subcontinent is poorly documented, and requires a taxonomic revision as a whole. The faunistic diversity of cladocerans comprises a clear representation of a tropical cladoceran assemblage.