Biswamoyopterus is a genus of rodent in the family Sciuridae. It contains three known species of very large flying squirrels, with B. laoensis being among the longest of all squirrels. They are distributed in forests in northeast India, southwest China and Laos. Despite their size, species in this genus tend to be very elusive; due to this, all of them have been described relatively recently. In fact 2 out of the 3 species are only known from a single specimen. Additionally, they are easily confused with certain Petaurista giant flying squirrels that are more common and overlap in range with the rare Biswamoyopterus.

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