Two new species of woolly flying squirrels (Eupetaurus cinereus) have been found in Southwest China’s Yunnan Province and Tibet Autonomous Region.

Two new species of woolly flying squirrels (Eupetaurus cinereus) have been found in Southwest China's Yunnan Province and Tibet Autonomous Region. 

The animals were discovered during a scientific expedition and biodiversity survey in Tibet's Shigatse and Yunnan's Nujiang by a team composed of Chinese, Australian and US researchers who published the research in the Zoological Journal of the Linnean Society on Monday.  

The team found that the flying squirrels in the central and eastern Himalayas have been separated from those in the western Himalayas by the Ganges River and Yarlung Tsangpo River, and they have significant differences in tooth structure and hair color as well as a genetic differentiation of 4.5 to 10.2 million years, according to a report sent to the Global Times by Gaoligong Mountain National Nature Reserve on Wednesday.

The study showed that the evolution of the flying squirrels is closely related to the rise of the Himalayas and changes in the rivers of South Asia. 

The two species have been named Eupetaurus tibetensis and Eupetaurus nivamons due to their location in Tibet and habitat, which is covered by snow, said Li Quan, one of the authors of the paper and a research fellow at Kunming Institute of Zoology, Chinese Academy of Sciences. 

The flying squirrel is commonly known as the "flying fox" in many parts of China, partly thanks to Fox Volant of the Snowy Mountain, a popular novel by Jin Yong.

The Eupetaurus cinereus is classified as endangered on the Red List of the International Union for Conservation of Nature, with an estimated number of only 1,000 to 3,000. 

The animal is known to be found only in the Himalayas. It is the largest gliding mammal at such a high altitude. 

Their food is mostly composed of coniferous tree leaves that are rich in tannins and other minerals, which makes it of great scientific value to study the adaptation of mammals to high altitude.

The wooly flying squirrel is one of the rarest and least-studied mammals in the world. Previous research found that those from Tibet and Yunnan are deeply divergent genetically from the ones in the western Himalayas, which shows a need to recognize more than one species in this genus, according to the recently published paper.