Palaeophis

Palaeophis ('ancient snake') is an extinct genus of marine snake whose fossils have been found in England, France, Denmark,[1] Morocco[2] and Mali,[3] dating back to the late Paleocene and Eocene epochs. The species P. colossaeus, known from a single vertebra, was originally estimated to exceed 9 m (30 ft) in length,[3] making it one of the largest known snakes, however most species of the genus were not as big (e.g. P. casei).