An international team of zoologists from Australia and China has discovered two new cryptic species in the genus Eupetaurus — which previously included only one species, the western woolly flying squirrel (Eupetaurus cinereus) — from the Himalayas.
The Yunnan woolly flying squirrel (Eupetaurus nivamons). Image credit: Quan Li.
The western woolly flying squirrel is among the rarest and least studied mammals in the world.
Weighing up to 2.5 kg and with a total length up to 110 cm (43.3 inches), it is one of the world’s largest gliding mammals.
This enigmatic species was originally described in 1888 by the British zoologist Oldfield Thomas from two skins and a skull that came from the Astor (now Astore) and Gilgit districts in northern Pakistan.
Between 1924 and 1994 it was thought to be extinct, until it was rediscovered by the scientific community in Pakistan.
“The western woolly flying squirrel is known to feed on pine needles and rest in rocky crevices, have the highest crown of cheekteeth among flying squirrels and is highly specialized — their feces, urine and hair hardens to make the substance Shilajit, which is used in traditional medicine,” said Australian Museum researchers Professor Kristofer Helgen and Dr. Stephen Jackson and their colleagues.
“However, the ecology of the new species remains poorly known and is in need of further research.”
The western woolly flying squirrel (Eupetaurus cinereus). Image credit: Oldfield Thomas, Journal of the Asiatic Society of Bengal.
In the study, the scientists measured and photographed museum specimens and reviewed published records of woolly flying squirrels.
They found that the genus occurs in three widely disjunct areas situated on the western (northern Pakistan and north-western India), north-central (south-central Tibet, northern Sikkim and western Bhutan) and south-eastern margins (north-western Yunnan, China) of the Himalayas.
Using both morphological examinations and molecular analyses, they found that these three populations represent distinct species.
Two of them are new species: the Tibetan woolly flying squirrel (Eupetaurus tibetensis) and the Yunnan woolly flying squirrel (Eupetaurus nivamons).
“In the Himalayas these extraordinary species live in the highest regions near the tree line above 3,500 m (11,500 feet) elevation,” they said.
“Their discovery helps to demonstrate the diversity of the world’s fauna and the great deal of work that still needs to be done to document and conserve the Earth’s biological diversity.”
“Much of this requires careful comparisons that can only be made in natural history museum collections.”
The findings were published in the Zoological Journal of the Linnean Society.
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Stephen M. Jackson et al. Across the great divide: revision of the genus Eupetaurus (Sciuridae: Pteromyini), the woolly flying squirrels of the Himalayan region, with the description of two new species. Zoological Journal of the Linnean Society, published online May 31, 2021; doi: 10.1093/zoolinnean/zlab018
