Predator X

Pliosaurus (a.k.a Predator X) was a pliosaurid plesiosaur from Late Jurassic Europe. It was the largest pliosaurid ever.

Description
Pliosaurus was a monster. It's bite force was four times as much as Tyrannosaurus rex- this could have crushed a 4 x 4 truck. Its four flippers could make it soar through the water at five metres a second. Palaeontologists have recently reduced its size from 15 meters, it was actually between 10 and 13 meters long, about twice the size of Liopleurodon.

Episode 4: Fight for Life
Pliosaurus is first seen in the open ocean, slowly swimming along. John Hurt explains it's discovery and size. It chases some Kimmerosaurus, but fails when they escape to a shallow water lagoon. Later, it returns when the tide rises, but in the shallow water, it fails to catch the agile prey. After the Allosaurus hunt, John Hurt tells us about violently ripped apart plesiosaur bones, and reveals a chilling story on a severly crushed plesiosaur skull, with a few vertebrae, but nothing else - it was missing it's body. After this, Pliosaurus spots a hunting Kimmerosaurus near the surface. it rushes up from below, stunning the prey by crashing into the lungs. After struggling to clear it, the Kimmerosaurus tries to swim away. Pliosaurus rips away a rear paddle, and zooms into the dark below. But just as it sees the nursery, Pliosaurus grabs the Kimmerosaurus, it's neck trapped in it's ravenous jaws. It crashes back into the sea, and shakes the prey. The neck is severed in mere seconds, and Pliosaurus shakes the corpse to pieces, finally getting it's longed-for meal.