Cavefishes of Meghalaya

Abstract

The state of Meghalaya, in northeast India, has many caves in the Jaintia, Khasi and Garo Hills districts. As per the available reports, over 1000 caves have been explored or partially explored to yield over 450 kilometres of surveyed cave passage in the state. The true cave-adapted species or troglobionts mostly occupy the cave’s deep zone, while some casual or occasional visitors are found at the entrance or to a depth of some extent. The troglobionts are characterized by depigmentation or albinos and, ultimately, lack of vision or very regressed vision with highly developed extra-ocular sensitive organs. In the 23rd February 2020 episode of Mann Ki Baat, the Prime Minister of India shared amazing facts about a rare fish species found by the biologist in the cave of Meghalaya and remarked that it is the largest among the cave-dwelling species existing in deep underground caves where even light cannot reach. After detailed molecular analyses, scientists found that the world’s largest cavefish from Meghalaya was a new species named Neolissochilus pnar. The present report documents for the fist time, a list of four true troglobiont species found only in the caves of Meghalaya, namely, Schistura sijuensis, Schistura papulifera, Schistura larketensis and Neolissochilus pnar. The Maan Ki Baat episode provided the insights to document the cave fishes of Meghalaya which will provide awareness to the stakeholders and local communities to conserve the cave fauna and their unique habitat.