Liopleurodon

Liopleurodon ("smooth-sided tooth") was a large pliosaur that lived during the Jurassic Period. Its fossils have been found in Europe.

Description
Liopleurodon had a large head and four paddle-like limbs, which allowed the animal to accelerate quickly. It was likely the apex predator of its time and location.

Size
The size of Liopleurodon is fiercely debated. L. B. Tarlo has suggested that the skull of a pliosaur is a valid factor in determining the animal's total size; on average, the head is around one-seventh of the Liopleurodon's length. If this is true, L. ferox would reach a length of 6 meters. However, discovery of more complete skeletons has shed doubt on this hypothesis: pliosaur skulls typically measured one-fifth of the animal's body length, and well-preserved specimens of L. ferox indicate that it only grew to seven meters or so in length.

Classification
A 2013 analysis placed Liopleurodon in the clade Thalassophonea, along with related pliosaurs Simolestes, Peloneustes, and Pliosaurus.

History
Liopleurodon was discovered and named in 1873 from only three teeth found in France. Each tooth was found in a different location, and each was given their own species, although only two species (L. ferox and L. pachydeirus) are valid today. Fossils of the genus have been found across Western Europe.

Diet
Liopleurodon was a carnivorous predator, able to kill and eat all sorts of marine creatures. It likely had a good sense of smell, and could scan the water with its nostrils in order to determine the location of a certain odor.

In popular culture
Liopleurodon was featured in the third episode of the BBC documentary series Walking with Dinosaurs. In the episode, one aging individual was depicted as measuring 25 meters in length, an inaccurate size based on modern evidence. Several Liopleurodon made a subsequent appearance in the BBC series Sea Monsters, attacking and eating a weakened Leedsichthys.