In a remarkable discovery that rewrites a chapter of Indian herpetology, scientists have confirmed that a non-venomous snake species, previously believed to exist only in southwestern China, has been residing in northeastern India for over four decades. The Zoological Survey of India (ZSI) revealed that the Yunnan keelback was misidentified earlier and has actually been present in Arunachal Pradesh since at least 1982.
A Historic Specimen and a Decades-Old Error
The story of this snake in India begins with a specimen collected by Scottish naturalist John Anderson during his 1868 China expedition. Anderson later described the taxon scientifically in 1879 based on three specimens held at the Asiatic Society of Bengal's Indian Museum, which were later transferred to the ZSI.
Fast forward to 1982, when ZSI scientist Dr. S Biswas recorded a snake in Gibbon's Land within the Namdapha Tiger Reserve, located about 16km east of Miao in Arunachal Pradesh. However, Biswas catalogued it as one of the common regional species. This misidentification meant the snake's true identity remained hidden in plain sight for 43 years.
Modern Taxonomy Solves an Old Mystery
The breakthrough came when researchers Sumidh Ray, Anirban Das, and Pratyush Mohapatra revisited historical specimens preserved in the ZSI section of the Indian Museum. By applying modern taxonomic tools, they re-examined both Anderson's original 19th-century specimen and the one collected by Biswas.
Their analysis proved that Biswas's 1982 discovery was, in fact, the first official record of the Yunnan keelback on Indian soil. This finding extends the known geographical range of the species significantly. Pratyush P Mohapatra, officer in charge of the Reptilia section at ZSI, emphasized the importance of the discovery.
"Known previously to be only from Yunnan Province in southwestern China, the species' distribution now extends into northeastern India, with the possibility of it occurring in adjacent Myanmar," Mohapatra said. "The discovery underscores the enduring scientific value of museum collections and the importance of revisiting old specimens."
Broader Implications for Border State Biodiversity
This discovery aligns with ZSI's intensified efforts to document fauna in India's border regions. ZSI director Dhriti Banerjee highlighted that the organization has ramped up surveys in states like Arunachal Pradesh, Rajasthan, and Gujarat.
"These focused surveys are crucial not only for discovering and documenting new species but also for confirming the presence of species within India's administrative boundaries," Banerjee stated. She added that earlier this year, ZSI signed a Memorandum of Understanding (MoU) with the Indian Army to bolster biodiversity exploration in frontier areas.
Through its centres in Itanagar and Jodhpur, ZSI will now collaborate with armed forces personnel to expand scientific surveys across challenging border landscapes. This partnership aims to uncover more hidden biodiversity treasures that may have been overlooked or misidentified in the past.
The research detailing the discovery of the Yunnan keelback in India has been published in the international scientific journal Zootaxa.
