Palaeophis ('ancient snake') is an extinct genus of marinesnake whose fossils have been found in England, France, Denmark,Morocco and Mali, 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, making it one of the largest known snakes, however most species of the genus were not as big (e.g. P. casei).
^ abRage, J.-C. (1983). "Palaeophis colossaeus nov. sp. (le plus grand Seprent connu?) de l’Eocène du Mali et le problème du genre chez les Palaeopheinae". Comptes Rendu de l’Academie des Sciences, Paris3 (296): 1741–1744.
^Holman, J. Alan 1982. Palaeophis casei, new species, a tiny palaeophid snake from the early Eocene of Mississippi. Journal of Vertebrate Paleontology. 2, (2), 163-166.