Abstract
The flying squirrel genus Biswamoyopterus (Rodentia: Sciuridae: Pteromyini) was once considered to contain three species, Biswamoyopterus biswasi from northeastern India, B. laoensis from central Laos and B. gaoligongensis from southwest China, all identified from morphological characteristics of one or two specimens. However, based on similar morphological characteristics of two samples of the genus Biswamoyopterus collected recently from northern Laos and northern Myanmar, and the small genetic distances on mitochondrial DNA and nuclear DNA between them, the results strongly support these two samples as representatives of the same species. The phylogenetic analyses strongly support Biswamoyopterus as an independent genus of Pteromyini, as a sister group to Aeromys. Biswamoyopterus biswasi is distributed in the northern Indo-China peninsula, where it is exposed to a series of threats, such as intense hunting activity, illegal trade, and rapid habitat loss; this should warrant its classification as critically endangered according to the International Union for Conservation of Nature (IUCN) Red List criteria. Here, the molecular data for genus Biswamoyopterus and two new specimen records from northern Laos and northern Myanmar are presented.