In June 2020, during the pandemic, Virender Bhardwaj, currently a doctoral student at Mizoram University, was exploring his backyard at his home in Himachal Pradesh in the western Himalayas, when he encountered an intriguing snake. He uploaded its photos on the social media app Instagram, and the images popped up on the feed of his colleague, Zeeshan Mirza. This led to three years of detailed investigations to identify the snake. The team recently published a paper revealing the discovery of an entirely new snake genus and species.
The snake resembled Liopeltis rappii, a species known to be distributed in the eastern Himalayas. However, the researchers noted that the population from Himachal Pradesh differed from the true Liopeltis rappii found in Sikkim with differences observed in the scales on the head and general colouration. The team confirmed this after examining specimens from natural history museums across Europe, the United States and India.
After comparing the DNA sequences generated from this snake with those of known species from across Asia, the researchers concluded that the snake from Himachal Pradesh is related to Liopeltis rappii but differs in several aspects to be called a new species. Both species belong to a new genus, Anguiculus, endemic to the Himalayas. Anguiculus refers to a “small snake” in Latin.
In honour of American actor and environmentalist, Leonardo DiCaprio’s work in creating awareness about increased biodiversity loss and climate change, the team named the snake Anguiculus dicaprioi with the suggested common name, “DiCaprio’s Himalayan snake”. Compared to other members of its family, the snake is small-bodied, growing to a maximum length of around half a metre and like other members of its family, it also has teeth.
“The scientists in this paper have uncovered a significant discovery in the biodiversity of the western Himalayas: the identification of a new genus of snakes,” says Bryan Fry, a professor at the University of Queensland, Australia. “These findings, stemming from a detailed analysis of the colubrid snake genera Gongylosoma and Liopeltis, underscores the uniqueness of the western Himalayan ecosystem and highlights its evolutionary distinction from the Eastern Himalayas,” adds Fry, who was not connected to the study.
“The authors find that some species warrant name changes to accurately reflect their ancestry, which benefits downstream research that is reliant on such information, and they describe a new genus that is quite distinct from the focal study organisms,” says Justin M Bernstein, who is affiliated with the American Museum of Natural History and was not part of the study.
Resulting from a similar Instagram post in June 2020, the team has also described a new-to-science snake species named Oligodon churahensis, after the Churah Valley in Himachal Pradesh, where the species was discovered.
Two distinct species
Members of the genus Anguiculus are small and are currently known by two species. These snakes are found at elevations above 1,500 metres across the Himalayas. The newly described species, Anguiculus dicaprioi is distributed from central Nepal to Chamba district in Himachal Pradesh, whereas Anguiculus rappii (which was earlier called Liopeltis rappii) is distributed in Sikkim, Bhutan and Arunachal Pradesh.
The new species, Anguiculus dicaprioi, has some features that distinguish it from other snakes in the same family. “The snake differs from most related snake genera in having a pore below the braincase to which muscles or cartilage attach,” explains lead author Zeeshan Mirza from the Max Planck Institute for Biology in Germany. “This pore has not been observed in related snake genera, and thereby, the snake from the Himalayas is a distinct group of its own from the related species from the eastern Himalayas (A. rappii),” Mirza notes.
“At first glance, A. dicaprioi has a creamish white belly and the lateral edges of the body are rounded whereas A. rappii, the belly is yellow and flat with a sharp ventro-lateral [front and side] edge,” observes Mirza. “The latter has a broad band on its neck even in the adult individuals, unlike A. dicaprioi.” He adds that “the two species have different numbers of scales bordering their parietal scale, and furthermore, their teeth number differs.”
Mirza points out that despite being widely distributed, these snakes are not commonly found. “The new species, A. dicaprioi is active from June to August, when one can encounter them basking on open paths. On the other hand, A. rappii is likely extremely rare; only two photographs of the species have surfaced from Bhutan in the last 10 years or so.”
A new genus
For around 180 years, the genera Liopeltis and Gongylosoma were said to be the same genera by many researchers while another group considered them distinct. “This could not be resolved as DNA data for the type species of the two genera was lacking,” Mirza explains. The DNA sequences presented in this paper of important species of the two genera helped reclassify species of these genera and aided in identifying an entirely new genus, Anguiculus.
“This recently published paper focuses on studying the evolutionary relationships of two lineages (genera) of snakes that have been long understudied,” says Bernstein. “These studies are important because we give species names to create a hierarchical organization that reflects ancestry, but the data used to form this organization has advanced over time,” he stresses.
According to Fry, “the study also revealed potential cryptic diversity within the genera, suggesting that many widespread species may harbour unrecognised genetic variation.” He adds that “this points to the need for further exploration and re-evaluation of known species in the region.”
Distinct biota
Scientists have the notion that the eastern Himalayas are biodiverse and that the biota of the western Himalayas is a subset of the biota from the eastern Himalayas. “However, the discovery of the new snake species A. dicaprioi and other taxonomic assessments of populations of reptiles from the western Himalayas suggests that the biota of the western Himalayas is distinct,” stresses Mirza.
Fry agrees, adding that the findings challenge the perception that the biota of the western Himalayas is merely an extension of the Eastern Himalayas. “Instead, they showcase the western Himalayas as a distinct evolutionary and ecological region, demanding targeted scientific and conservation efforts.”
If a species is found to be distinct and listed as a separate species, its conservation status would be evaluated differently, says Mirza. He gives the example of Sinomicrurus macclellandi, a species of coral snake distributed from Nepal to the whole of northeast India and some parts of Southeast Asia.
“During our surveys, we found a snake of the genus Sinomicrurus in Himachal and DNA sequences and morphological data suggested that the species is distinct from Sinomicrurus macclellandi.
However, this snake was recorded from near Shimla in 1908-1910 and was regarded as a new subspecies of Sinomicrurus macclellandi as ‘nigriventer’.” Detailed investigations confirmed that the Himachal population of this snake is a fully distinct species. “So, if we considered it as a variety or subspecies of Sinomicrurus macclellandi,” which is widespread, “it would not get special attention with regards to its conservation,” Mirza points out.
Wikimedia Commons (CC BY SA 2.0).
Herpetofauna needs more exploration
Mirza urges more dedicated surveys of the western Himalayas including DNA sequencing of all known species in the region to evaluate the status of reptiles in the region. “I am certain that more interesting reptiles and other lesser-studied taxa will be discovered with more focused surveys.”
Herpetofauna in the western Himalayas remain underexplored, concurs Fry. “Comprehensive surveys and studies are essential to uncover the region’s hidden biodiversity” paving the way to identifying new genera and species, he says.
“This new genus discovery is a testament to the incredible, yet often overlooked, biological wealth of the western Himalayas and underscores the urgency of safeguarding this natural heritage. With increasing threats from habitat destruction, climate change, and human activities, it is imperative to protect the fragile ecosystems of the western Himalayas,” asserts Fry. “Conservation strategies must integrate findings like these to ensure the preservation of this unique biota.”
Fry emphasises that “this finding should inspire renewed commitment from researchers, policymakers, and conservationists to explore and protect the hidden treasures of the western Himalayas before they are lost forever.”
This article was first published on Mongabay.
