Trimeresurus cf. albolabris

The white-lipped pit viper, Trimeresurus albolabris, is a green, arboreal pit viper with yellow, white or pale-green sides to the head. Males reach about 600mm and females about 810mm. It eats birds, small frogs and small mammals and holds its prey until it dies rather than striking and releasing it (Wikipedia, general species account).

Its venom is mainly haemotoxic and bites range from mild to fatal, though deaths are few. Gray described it in 1842, and its genus has moved between Trimeresurus and Cryptelytrops. The source lists Nepal in its range. The Nepal list uses cf. because the identification of Nepal animals is uncertain (Wikipedia, general species account).