this is a wrong pic bro.. as i know this is boiga ceylonensis.. in sinhala nidi mapila,,, and mildly venomous..
Above comment very correct. Pls remove the picture.
Kunakatuwa is bit venomous. not highly. Cobra, Russels Viper(thith polanga), Saw scale Viper)Wali polanga), Sri lankan Krait (moodu karawala), Common krait (Thel karawala) are the highly venomous.