Plesiosaur is an underwater reptile that was not a dinosaur but lived with them. Plesiosaur means Close to lizard. The Plesiosaur lives over 2 million years ago wow! From the tip of its nose to the end of its tail it was over 6 feet long! It ate small animals that roamed the sea close to the bottom. A cool fact is you may see many pictures of Plesiosaur with bent necks but now many scientist believe that its neck could move so slightly by the way the neck bones were placed.