Meet the new species of venomous pit viper described from India
When Rohan Pandit and Wangchu Phiang accidentally stumbled upon a brown snake on a steep slope of a forest in the northeastern state of Arunachal Pradesh in India, little did they know that the reptile had never been formally described before. Now, in a new paper, researchers have described this snake as a new-to-science species of pit viper named Trimeresurus arunachalensis, or Arunachal pit viper.
Both Pandit, an Indian wildlife researcher and a co-author of the paper, and Phiang, a member of the indigenous Bugun tribe, were part of a biodiversity survey project at the time. They had been walking through a forest near the village of Ramda in West Kameng district when Phiang spotted the snake amid the leaf litter.
He pointed it out to Pandit, and the latter was quick to note that the snake was a species of viper, a group of venomous snakes with folding fangs, but unlike any other viper he’d encountered in India before. “At that time we really had other priorities. We had to reach another place, so we just bagged the snake,” Pandit said. “Later on when we returned to the camp we checked it properly. It was pretty apparent then that it was something I had never seen before in any snake book.”
What caught Pandit’s attention was the snake’s “peculiar” pointed snout that resembled that of the hump-nosed viper (Hypnale hypnale). The hump-nosed viper, however, is found farther away in peninsular India and the Western Ghats. “At first, I was surprised that maybe hump-nosed vipers are also found in northeast India,” Pandit said. “There are also similar looking snakes in Borneo and southeast Asia … so initially we thought this snake might be a range extension of those species.”
To get a clearer picture, a team of researchers, including Pandit, went on to study the specimen in detail. They took measurements of the animal, noted its number and pattern of scales, and analyzed its anatomy, comparing them to those of all other known species of vipers found in Asia. They also extracted DNA from it and analyzed it in a lab at the Indian Institute of Science (IISc) in Bengaluru (formerly Bangalore), said Deepak Veerappan, currently a herpetologist at the Natural History Museum, London, who was a postdoctoral student at IISc at the time of the analysis.
The researchers found that the Arunachal pit viper had a very different scale count compared to all known mainland pit vipers of northeast India and nearby China. Results from genetic analysis added further evidence that the species Pandit had encountered was indeed a new one, closely related to the Tibetan pit viper (Trimeresurus tibetanus), a snake known only from Tibet. But physically and anatomically, the two species are quite distinct, the researchers say.
