New species of rabbit-like pika discovered in India

In the remote upper reaches of the Eastern Himalayas in Sikkim, India, scientists have discovered a new species of pika, a cute rabbit-like mammal.

The new species — named Sikkim pika or Ochotona sikimeria — was previously classified as a sub-species of the Moupin pika or Ochotona thibetana, known to occur in the mountains of the eastern Tibetan Plateau and along the Himalayan ridge in China, India, Myanmar, and Bhutan.

“Many people have photographed O. sikimaria and there are several specimens in museum collections of India,” lead author Nishma Dahal, a PhD student at the National Centre for Biological Sciences in Bangalore, India, told Mongabay. “It is also the most common pika species in Sikkim. So it’s not as if no one had seen this animal before. However, because it looked like O. thibetana, it was classified as a subspecies of this species.”

In fact, the Sikkim and Moupin pika look nearly identical, researchers write in the study published in Molecular Phylogenetics and Evolution. The slight differences in their morphology — which often go unnoticed in the field — can only be teased apart with careful skull measurements, according to Dahal.

So instead of relying on error-prone methods of identifying species based on their morphological features, the researchers turned to the animal’s DNA. By analyzing the pika’s genetic data sampled from its poop, and comparing it with the DNA of other related pikas, the team found that not only is the Sikkim pika a distinct species, it is not even closely related to the Moupin pika with which it shares the highest morphological similarities.

“This is a solid study and one that was much needed,” Andrew Smith, a pika expert from the Arizona State University who was not involved in the study, told Mongabay. “It made no sense that O. sikimaria was classified within O. thibetana, but without an investigation, it could not be identified as an independent form. The work was very well done, and addressed the pressing need to determine the status of the pikas found in Sikkim.”

So far, the new species is known only from the state of Sikkim, the researchers say. Field work in other Himalayan regions of Arunachal Pradesh, Central Nepal (Annapurna and Langtang), Ladakh and Spiti has failed to uncover this species, but further surveys in Bhutan and eastern Nepal are being considered.

In fact, since pikas in India occur in remote high elevations of the Himalayas, they remain poorly studied. However, like the American pika that is disappearing across its range due to climate change, the Sikkim pika, too, is likely to be negatively affected by climate change, co-author Uma Ramakrishnan of NCBS told Mongabay. So an improved understanding of the pika’s biology and ecology is necessary to plan conservation efforts for the tiny mammals, she added.

But at the moment, the new species seems to be abundant in Sikkim and may not be immediately threatened by extinction. The Sikkim pika’s actual conservation status, however, is yet to be evaluated.

“The only data we had on this form of pika indicated that the habitat at the type locality had been trashed and that the population was threatened,” Smith said. “This study not only solved the taxonomic issue, but it found that this pika was very common, thus not at risk of endangerment – which was terrific news.”

CITATION:

• Dahal, N. et al. Genetics, morphology and ecology reveal a cryptic pika lineage in the Sikkim Himalaya. Mol. Phylogenet. Evol. 106, 55-60 (2016) doi: 10.1016/j.ympev.2016.09.015