Red-necked Keelback

The red-necked keelback is a species of venomous snake in the subfamily Natricinae of the family Colubridae. Unusually for colubrids it is venomous. The account used here says that following a taxonomic revision it is restricted to the Indonesian islands of Java and Sumatra, though it was historically considered much more widespread, so its Malaysian listing should be checked (Wikipedia, general species account).