A common medium-sized, highly venomous, terrestrial snake. The typical subspecies inhabits the forests of the wet and intermediate zones. Widespread in the plains, in thinly-wooded forests, agricultural field as well as edges of human habitation, it prefers cool, damp habitats, such as under logs, leaf litter, stones, crevices, holes in embankments and rat burrows. Nocturnal when foraging, it hides under piles of debris during the day and sometimes enter the human habitation. Confined to the wet and parts of the intermediate zones. Known from Peradeniya, Kandy, Knuckles, Gampola, Opatha, Ratnapura, Balangoda, Sinharaja, Peak Wilderness, Gurutalawa, Mawanella, Bandarawela, Galle and Matugama. The montane populations of this species ( subspecies karawala) is smaller than the lowland population. Restricted to rocky biotope and leaf litter in wet forests including Horton Plains, Hakgala, Rangala, Dimbulla,Badulla,Balangoda, Kalupahana, Haldummulla and Punagala.