Palaeophis is the first creature that existed outside the Mesozoic era to be confirmed for Beasts of Bermuda. See here for a full list of confirmed, discussed, and likely creature additions to the game.
This giant sea snake lived in the Cretaceous era and Eocene epoch. Being a sea snake, it was very likely accustomed to living and preying on the creatures of the open ocean. It was a carnivore, and is currently planned to function as a semi-aquatic creature in the game. Its in-game abilities are still being decided upon, but it is a possibility that it may feature venom. Palaeophis will likely be able to enter the burrows of Oryctodromeus. Its main environment will probably be shallow waters, similar to Lurdusaurus. It may have low health and be vulnerable to ambushes by Mosasaurus or Kronosaurus.
It is very likely that this creature will not be playable for the public in quite some time.