Wagler's Pit Viper is perhaps the most well-known of the green, arboreal pit vipers to be found in the region. This is a snake of primary forest, mature secondary forest and mangroves. It is active by night; by day it generally lays coiled high in the trees. As with other pit vipers, this species has haemotoxic venom, meaning it is poisonous to the blood system. The species can be identified by the triangular head. Juveniles are mainly light green with narrow pale bands, and adults are dark green with thicker yellowish bands.