For more than 160 years, the Himalayan pit viper was believed to be a single species, found across the Himalayas in Pakistan, India and Nepal. Now, a new study revealed this snake is actually not one, but five distinct species, including three entirely new to science.
For their analysis, the researchers conducted fieldwork to different parts of the Himalayas and collected samples of what was considered to be the Himalayan pit viper from different populations. They also examined historical specimens assigned to the Himalayan pit viper and extracted DNA from them.
Their analysis of the snakes’ bodies, skeleton and DNA revealed five separate species:
The Himalayan pit viper (Gloydius himalayanus) was first described in 1864. This species is now restricted to northwestern India and typically inhabits elevations between 1,000 and 3,500 meters (3,281-11,483 feet).
The Chamba pit viper (G. chambensis) was originally described in 2022 from India’s Chamba District. This study extended its known range westward into the Kashmir Valley. It lives at elevations from 400-2,500 meters (1,312-8,202 feet).
The Hazara pit viper (G. hazarensis) is a new-to-science species. It’s found in the Hazara region of northeastern Pakistan at elevations ranging from 1,630-2,900 meters (5,348-9,514 feet).
The Hindu Kush pit viper (G. hindukushensis) is also a newly described species. It inhabits the eastern foothills of the Hindu Kush Mountains in northwestern Pakistan between 1,660 and 2,888 meters (5,446-9,475 feet).
The Nepali pit viper (G. nepalensis) is new-to-science as well. This viper is distributed across western and west-central Nepal and is recorded at elevations between 1,640 and 3,220 meters (5,380-10,564 feet).
Anita Malhotra, a pit viper specialist at Bangor University, U.K., who wasn’t involved in the study, told Mongabay by email that five pit viper species occurring in close proximity wasn’t surprising. They were presumably isolated by the “extreme topography of the mountains,” she said, adding that their small ranges make them “extremely vulnerable to climate change.”
The study’s authors wrote that major river valleys, such as the Indus and Karnali, may have acted as historical barriers driving this isolation.
“This discovery highlights the need to treat fragile ecosystems as reservoirs of highly localised evolutionary diversity,” Kartik Sunagar, a venom expert at the Indian Institute of Science who wasn’t involved in the research, told Mongabay through email. “It also shows why taxonomy is central to conservation: if we do not recognise distinct species, we cannot accurately assess their risk or protect them effectively.”
The study’s authors wrote newer technologies that allow DNA to be retrieved from museum specimens preserved in formalin, helped in the Himalayan pit viper’s re-analysis. Malhotra cautioned that the process of DNA extraction from specimens is “difficult and expensive” and “involves destructive sampling of museum specimens, which not all museums will allow.”
Banner image: Gloydius nepalensis from Nepal. Image courtesy of Dr. Daniel Jablonski and Dr. Frank Tillack (CC BY).
Credits
