Snake photo posted on Instagram leads to the discovery of a new species from the Himalayas

An image on Instagram prompted the discovery of a new species of Kukri snake from Himachal Pradesh, India. Intrigued by a post shared by a master student, the research team found and examined more specimens to discover they belonged to a yet undescribed species. Their study, published in the open-access journal Evolutionary Systematics, highlights how little we still know about the biodiversity in the Western Himalayas.

Virender Kumar Kharadwaj

Intrigued by a photo shared on Instagram, a research team from India discovered a previously unknown species of kukri snake.

Staying at home in Chamba because of the COVID-19 lockdown, Virendar K. Bhardwaj, a master student in Guru Nanak Dev University in Amritsar, started exploring his backyard, photographing everything he found there and posting the pictures online. His Instagram account started buzzing with the life of the snakes, lizards, frogs, and insects he encountered.

One of those photos – a picture of a kukri snake – popped up in the feed of Zeeshan A. Mirza (National Centre for Biological Sciences, Bangalore) and immediately caught his attention. After a chat with Harshil Patel (Veer Narmad South Gujarat University, Surat), he decided to get in touch with Virendar and find out more about the sighting.

The snake, which Virendar encountered along a mud road on a summer evening, belongs to a group commonly known as Kukri snakes, named so because of their curved teeth that resemble the Nepali dagger “Kukri”. 

At first sight, the individual that Virendar photographed looked a lot like the Common Kukri snake (Oligodon arnensis). However, a herpetologist could spot some unique features that raised questions about its identity. 

Kukri snake

Virendar uploaded the photo on 5 June 2020, and by the end of the month, after extensively surveying the area, he found two individuals – enough to proceed with their identification. However, the COVID-19 pandemic slowed down the research work as labs and natural history museums remained closed. 

Upon the reopening of labs, the team studied the DNA of the specimens and found out they belonged to a species different from the Common Kukri snake. Then, they compared the snakes’ morphological features with data from literature and museums and used micro computed tomography scans to further investigate their morphology. In the end, the research team were able to confirm the snakes belonged to a species previously unknown to science.

The discovery was published in a research paper in the international peer-reviewed journal Evolutionary Systematics. There, the new species is described as Oligodon churahensis, its name a reference to the Churah Valley in Himachal Pradesh, where it was discovered. 

What’s even more interesting is that the exploration of your own backyard may yield still undocumented species… if one looks in their own backyard, they may end up finding a new species right there.

Zeeshan A. Mirza

“It is quite interesting to see how an image on Instagram led to the discovery of such a pretty snake that, until very recently, remained hidden to the world,” comments Zeeshan A. Mirza.

“What’s even more interesting is that the exploration of your own backyard may yield still undocumented species. Lately, people have been eager to travel to remote biodiversity hotspots to find new or rare species, but if one looks in their own backyard, they may end up finding a new species right there.”

“Compared to other biodiversity hotspots, the Western Himalayas are still poorly explored, especially in terms of herpetological diversity, but they harbor unique reptile species that we have only started to unravel in the last couple of years,” Mirza adds.

Research article:

Mirza ZA, Bhardwaj VK, Patel H (2021) A new species of snake of the genus Oligodon Boie in Fitzinger, 1826 (Reptilia, Serpentes) from the Western Himalayas. Evolutionary Systematics 5(2): 335-345. https://doi.org/10.3897/evolsyst.5.72564

Guest blog post: Unique feeding behaviour of Asian kukri snakes gutting frogs and toads

Guest blog post by Henrik Bringsøe

In September 2020, we reported the first evidence for a newly discovered behaviour in snakes, as we provided extensive photographic documentation, demonstrating a macabre feeding strategy of Asian kukri snakes of the species Oligodon fasciolatus, the Small-banded Kukri Snake: a snake cutting open the abdomen of a toad, inserting its head and pulling out the toad’s organs which are then swallowed.

A Small-banded Kukri Snake attacking a Painted Burrowing Frog, which is inflating its lungs. The snake makes rotations about its own longitudinal body axis (“death rolls”), as it is biting and holding the belly of the frog. Video by Navapol Komanasin.

This is done while the toad is alive and it may take several hours before it dies! We have now provided new evidence that two other species of kukri snakes also exhibit this highly unusual behaviour: Oligodon formosanus, the Taiwanese Kukri Snake, and Oligodon ocellatus, the Ocellated Kukri Snake. These three species are closely-related and belong to the same species group in the genus Oligodon.

On two occasions in Hong Kong, a Taiwanese Kukri Snake was observed eviscerating frogs of the species Kaloula pulchra, the Painted Burrowing Frog or Banded Bullfrog. In one case, the snake had cut open the belly of the frog and inserted its head deep into the frog’s abdomen. In this position, the snake performed repeated rotations about its own longitudinal body axis, also called “death rolls”! We believe that the purpose of these death rolls was to tear out organs to be subsequently swallowed. In the other case, the organs of the frog had been forced out of its abdomen.

A Taiwanese Kukri Snake with its head buried deep into the abdomen of a Painted Burrowing Frog. Initially, the frog moves its long fourth toe of the left hind foot up and down 21 times. During the subsequent active struggle, the snake makes three “death rolls”. Video by Jonathan Rotbart.

A Small-banded Kukri Snake was also observed eating a Painted Burrowing Frog in Northeast Thailand, but it swallowed the frog whole. That snake also performed death rolls, although we have never before seen that behaviour in this species of kukri snake (this species was treated in our 2020 paper). This frog is not considered toxic and is also eaten by other snakes. We believe that prey size is crucial in determining whether the gape width allows large prey to be swallowed whole by kukri snakes. If the prey is too large, the snake may eviscerate a frog or toad, in order to swallow the organs. Afterwards, the snake will perhaps be able to swallow the rest of the frog or toad.

In another new paper, we describe and illustrate the Ocellated Kukri Snake eating the toxic toad Asian Black-spotted Toad (Duttaphrynus melanostictus) in Vietnam. Initially, the large snake’s head was buried past its eyes into the abdomen of the toad, but eventually the snake swallowed the toad whole despite its toxicity. We interpret this behaviour that kukri snakes are in fact resistant to the toads’ cardiac glycoside toxins. Furthermore, toads are only eviscerated if they prove too large to be swallowed whole.

An Ocellated Kukri Snake first pierced this poisonous Asian common toad and buried its head deeply into the abdomen of the amphibian, as it was probably eating the organs. However, as seen in the photo, the kukri snake proceeded to swallow the toad whole. 
Photo by James Holden.

We suggest that the unique behaviour of eviscerating frogs and toads and eating their organs may have evolved specifically in a group of kukri snakes named the Oligodon cyclurus group or clade because it has now been recorded in three of its species, namely Oligodon fasciolatus, Oligodon formosanus and Oligodon ocellatus. We hope that future observations may uncover additional aspects of the fascinating feeding habits of kukri snakes though we may indeed call them gruesome.

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See more video recordings of the snakes’ unique, even if quite gruesome, behaviours provided as supplementary files to one of the discussed research papers.

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Research papers: 

Bringsøe H, Suthanthangjai M, Suthanthangjai W, Lodder J, Komanasin N (2021) Gruesome twosome kukri rippers: Oligodon formosanus (Günther, 1872) and O. fasciolatus (Günther, 1864) eat Kaloula pulchra Gray, 1831 either by eviscerating or swallowing whole. Herpetozoa 34: 49-55. https://doi.org/10.3897/herpetozoa.34.e62688

Bringsøe H, Holden J (2021) Yet another kukri snake piercing an anuran abdomen: Oligodon ocellatus (Morice, 1875) eats Duttaphrynus melanostictus (Schneider, 1799) in Vietnam. Herpetozoa 34: 57-59. https://doi.org/10.3897/herpetozoa.34.e62689