Hydrophidae

A family of sea snakes comprising about 50 species with flattened oar-like tails used as sculls. They are found mostly in the coastal waters of south Asia and Australia. The largest reach a length of almost 9 feet but most species are only about a third as long. They are all venomous. (Goin, Goin, and Zug, Introduction to Herpetology, 3d ed, pp331-3; Moore: Poisonous Snakes of the World, 1980, p159).