Thiruvananthapuram: A new genus of freshwater crab has been discovered from two habitats in Kerala with least human intervention. According to the scientists who discovered the genus ‘Karkata’, which means crab in Sanskrit and Malayalam, this is only the tip of the iceberg. Kerala, which now has the highest freshwater crab diversity, is likely to be home to many more unknown species and even genus of crabs, they say. “Crabs are not migratory, and their distribution is limited. So there could be many more freshwater species endemic to each river basin,” says A. Biju Kumar, professor and head of the department of aquatic biology and fisheries, University of Kerala.
With their discovery, the number of known freshwater crab species in Kerala has become 35, which include 24 endemic species. Pati says the level of endemism seen in freshwater crabs is unusually high and nearly two-third species of Kerala are endemic to the region. They say some freshwater crab species might have already disappeared because of habitat destruction. Crabs found in low-lying farmlands and tea estate hills might have become extinct because of the use of pesticides, he says.