The common slug snake, Assam snail eater, Assam snail-eater snake, or montane slug-eating snake (Pareas monticola) is a species of snake found in Northeast India (Sikkim, Assam, Meghalaya, Mizoram, Darjeeling, Arunachal Pradesh), eastern Nepal, Bhutan, China (Tibet, Yunnan), Myanmar, and Vietnam. Its type locality is "Naga Hills, Asám" (=Assam), India. It is also reported from north-eastern and south-eastern Bangladesh. The species was first described by Theodore Cantor in 1839. Pareas monticola is a nocturnal and arboreal snake that typically occurs in low vegetation and preys on slugs and snails.