Chinese researchers have discovered two rare flying squirrels in the Tibet Autonomous Region during field surveys. After verification, they are identified as the Bhutan giant flying squirrel, a new record species for Chinese mammals, and the Li's dwarf flying squirrel, a new record species for mammals in the Tibet Autonomous Region. The relevant research findings were recently published in the academic journal Acta Theriologica Sinica.

The image depicts a Bhutan giant flying squirrel. (Photographed by Zeng Xiangle)

The first author of the paper, Associate Research Fellow Li Quan from the Kunming Institute of Zoology, Chinese Academy of Sciences, introduced that squirrels are divided into three types based on their lifestyle: tree squirrels, ground squirrels, and flying squirrels. In Chinese, flying squirrels are referred to as "wú shǔ" (large-bodied) or "fēi shǔ" (small-bodied). Fossil records indicate that flying squirrels originated in Europe or North America. After acquiring the ability to glide, flying squirrels significantly expanded their range and diversity compared to other squirrel "relatives" with similar phylogenetic positions. They are widely distributed across various forested regions of Eurasia and North America, with weights ranging from grams to over kilograms.

The image shows a Petaurista magnificus. (Photo by Zeng Xiangle)

Today, Asia has the most living flying squirrels, especially in the eastern Himalayas and the Sunda Islands. The newly discovered species is located in the eastern Himalayas. Li Quan said that the Bhutan giant flying squirrel had no previous definite records in the country, and this is the first official record of the species in the country. It is evaluated by the International Union for Conservation of Nature () as a near-threatened species; the Li's dwarf flying squirrel was previously known to be distributed only in the northwest of Yunnan Province, China, and the northern part of Myanmar. This is a new record of mammals in the Tibet Autonomous Region, and due to insufficient survey data, it has not yet been evaluated.

Image: Hand-drawn illustration of the Petaurista magnificus (Li's flying squirrel). (Drawn by Zheng Qiuyang)

Experts believe that this discovery expands the understanding of the distribution areas of the Bhutan giant flying squirrel and the Lee's small flying squirrel, reflecting the rich biodiversity of the Himalayan region. It is necessary to further strengthen biodiversity surveys and monitoring research in the Himalayas to discover more new species and records. This study was supported by the Second Comprehensive Scientific Expedition to the Qinghai-Tibet Plateau, the National Natural Science Foundation of China's Youth Science Fund, and the "Xing Dian Talent Support Plan" of Yunnan Province.