Barbastella leucomelas
Habitat
Mountainous areas at moderate elevations; probably roosts in caves, rock crevices and tree hollows; recorded foraging over streams
Range
Himalaya and China, south to Vietnam; Afghanistan to Taiwan
The account used here is for the eastern barbastelle, Barbastella darjelingensis, described by Brian Houghton Hodgson in 1855 and split from the Arabian barbastelle (B. leucomelas) in a 2008 study. It ranges across much of Asia from Afghanistan to Taiwan, through the Himalaya and China south to Vietnam, favouring mountainous areas at moderate elevations (Wikipedia, general species account).
It probably roosts in caves, rock crevices and tree hollows and has been recorded foraging over streams. The source does not name Nepal specifically and gives no size, appearance or diet detail (Wikipedia, general species account).