Seventy-one species of reptiles belonging to nine families have been recorded from Sinharaja. Nearly half of these are endemic, whilst 33 are nationally threatened. The reptiles in Sinharaja include tree-living forms (agamid lizards, geckos and some serpents), ground-dwelling forms (many serpents and skinks), and burrowing forms (earth snakes).
The serpents in Sinharaja include non-poisonous species such as the Rat snake (Coluber mucosus) and Kukri snakes (Oligodon spp), mildly poisonous species such as the Green Pit-Viper (trimeresurus trigonocephalus) and highly venomous species such as the Cobra (Naja naja), Common Krait (Bungarus caerullleus) and the Russell’s viper (Daboia russellii). The Indian Python (Python molurus), which is the largest serpent in Sri Lanka, occurs throughout the Sinharaja forest region.