An overview of freshwater Tardigrada in Northern Western Ghats of India

We investigated the freshwater habitats of Northern Western Ghats of India to study the diversity and distribution of tardigrades. There has been no report, till date, on the freshwater tardigrade fauna of Western Ghats. In the six-year study period, we found species belonging to only six genera. The report presents details of abiotic factors and habitats in which tardigrade species were found. Freshwater tardigrades are known to occur in permanent and temporary habitats; however, in the present study, 83.3% of tardigrade positive samples were found to occur in temporary habitats only. Out of 211 samples from different habitats only 12 samples were tardigrade positive. Dactylobiotus and Thulinius were the most commonly occurring genera. Tardigrades were found to co-occur with other taxa in 91.6% of tardigrade positive samples, predominated by rotifers followed by nematodes. The occurrence of Doryphoribius in a limestone cave having unique geological feature of stalactites and stalagmites, gives new insights on Tardigrada and their microhabitat preferences. Their distribution in such unique habitats highlights the importance of these habitats in harbouring the unique fauna.