Pliosaurus was a large short-necked Plesiosaur that lived during the late Jurassic period (155-145 mya) in Europe. The largest species was Pliosaurus funkei, known informally as "Predator X". P. funkei is known from 2 specimens composed of 20,000 fragments found on the island of Svalbard, Norway. It grew to nearly 13 meters (43 feet) and weighed upwards of 4-8 tons (8,000-16,000 lbs).
Pliosaurus, like other large members of its family, ate other sea reptiles such as long-necked Plesiosaurs and Ichthyosaurs. Pliosaurs probably bit the fins off of prey to disable them before they killed them, much like modern Orcas do to large Baleen whales.
It was an apex predator during the late Jurassic. Studies of the skull have shown that it could probably scan the water with its nostrils to ascertain the source of certain smells.
Jurassic Park Inspired Games
Pliosaurus appears in Jurassic Park: Builder as part of the Aquatic Park. It is a limited edition animal, only available for a short time period.
Pliosaurus appears in Jurassic World: The Game as a Legendary Reef creature.