Merrem’s Hump-nosed Pit Viper/පොලොන්තෙලිස්සා/කුණකටුව/ගැට පොලගා[Polon Thelissa/Kunakatuwa/Gata Polaga] (Hypnale hypnale)

Common venomous terrestrial snake found in anthropological habitats and plantations (Especially tea, coconut and rubber plantations) from coastal areas up to about 600m of the central hills. More abundant in the south-western wet zone than in the northern and eastern dry lands. However it appears to be absent in undisturbed forests in Sri Lanka.  It is a nocturnal snake and during the day time rest under stones, logs and among leaf litter sometime with its head keep at an angle of 45 degrees to its body resembling a dry leaf. When  disturbed it flattened its body, forms it into ‘S’ shaped loops, often vibrates the tail and lashed out. Rapid tongue protrusion has been observed too.  It preys on skinks, shrews, geckos, frogs and rodents. Instances of feeding on reptile eggs and snakes are also observed. Merrem’s Hump-nosed Viper is responsible for the highest incidents of snake bites in Sri Lanka (~27%) with occasional fatalities though its venom is considered as moderate.