6 days ago
New freshwater crabs discovered in the Western Ghats in Kerala
Recent studies launched by researchers at the Department of Aquatics Biology and Fisheries, University of Kerala, have led to the discovery of a new genus and two new species of freshwater crabs from Western Ghats regions in Kerala.
The new genus and species, belonging to the freshwater crab family Gecarcinucidae, was spotted in the Ranipuram Hill Station, Kasaragod district. It has been named Kasargodia sheebae. The other new species, also from the Gecarcinucidae family, was spotted in Gavi, Pathanamthitta district. This species belongs to the genus Pilarta and has been named Pilarta vaman, the researchers said.
The Journal of Crustacean Biology has published the findings on Kasargodia sheebae, while a paper on the Pilartavaman has appeared in the journal Zootaxa. Both discoveries are by the same team; Smrithy Raj and A. Biju Kumar from the Department of Aquatics Biology and Fisheries, and Peter K.L. Ng, Lee Kong Chian Natural History Museum, National University of Singapore.
In the case of Kasargodia sheebae, the name of the new genus, Kasargodia, is derived from the northernmost Kerala district, while the species name is derived from the name of Sheeba Smrithy Raj, the wife of Smrithy Raj who assisted him on field trips. Kasargodia sheebae is distinguished by brownish-orange carapace with numerous black spots. The limbs bearing the claws are orange with black spots. The specimens were collected from a small mountain stream flowing through grasslands.
The other new species, Pilarta vaman, is named after Vaman, one of the avatars of Vishnu in Hindu mythology. The name alludes to the small size of this crab. The carapace of this species is more quadrate. Specimens were collected from a small mountain stream at Gavi. 'The crabs appear to be rare, as only two individuals were found,' the Zootaxa paper noted.
The Western Ghats mountain range harbours many endemic freshwater crab species, as proven by numerous recent discoveries, the researchers said. 'The actual diversity of freshwater crabs in the Western Ghats is unclear, because of their secretive nature and they are difficult to collect. Most are nocturnal and hide in deep burrows, presenting a challenge for researchers,' they said.
The endemism of freshwater crabs in the Kerala section of the Western Ghats, which is close to 70%, is higher than that of any other group of organisms. However, both Kasargodia sheebae and Pilarta vaman face anthropogenic threats, according to the researchers. The tourist flow to the grasslands where these crabs were found pose significant threats to their habitats, they said.
