A team from the Zoological Survey of India has found, scuttling in the crevices of boulders of Arunachal Pradesh’s forests, a new species of freshwater crab. “The Teretamon ke-mpi is a 1.5-inch round-shaped crab — extremely small and residing below small stones in creeks and semi-dry areas. That is why many people have overlooked it so far,” says Santanu Mitra, Assistant Zoologist, Zoological Survey of India.
In April 2018, Mitra and his team discovered the new species “just walking below the stones” at Arunachal Pradesh’s Namdapha Tiger Reserve in Changlang district. The National park, so named in 1983, is the largest protected area in the Eastern Himalayan Biodiversity Hotspot. “At first sight, I knew the crab was interesting — it’s top portion is extremely smooth, just like porcelain. We immediately examined it in the lab and that is when we realised it was a new, undiscovered species,” Mitra says, “This was in March 2018.”
Now the journal Zootaxa has reported the discovery by a three-membered team from the ZSI including Mitra, Arajush Payra and Dr Kailash Chandra, Dirtector, ZSI. The invertebrate has been named after Stanley W. Kemp (1882–1945), an English marine biologist who was the former superintendent of the ZSI. “He has discovered a number of specimens from Arunachal Pradesh and this was our way of honouring him,” says Mitra, who believes that if the region is explored thoroughly, the discoveries will double. Currently, there are 1,000 species of marine crabs and 120 species of freshwater crabs in India. “In Northeast, there are 45 species of freshwater crabs, with Arunachal Pradesh having 10 alone,” he says, adding that “Very little work has been done in the Namdapha Tiger Reserve because most of the areas are still inaccessible to humans since the forests are so dense.”
The discovery just goes to show the potential of Arunachal Pradesh as one of the richest — yet unexplored — biodiversity hotspots in the country. “It also throws up interesting facts about crabs as well as the region it is found in,” says Mitra, “The crab serves as a great environmental indicator. You don’t find a single crab in areas with polluted waters.”