Liopleurodon

From Wikipedia, the free encyclopedia

iLiopleurodon
Fossil range: Late Jurassic

Liopleurodon ferox harassing Leedsichthys problematicus

Extinct (fossil)

Scientific classification

Kingdom:	Animalia
Phylum:	Chordata
Class:	Sauropsida
Order:	Plesiosauria
Suborder:	Pliosauroidea
Family:	Pliosauridae
Genus:	Liopleurodon Sauvage, 1873

Species

L. ferox (type)
L. pachydeirus
L. rossicus
L. macromerus

Liopleurodon (Leo-PLOO-ra-don, meaning 'smooth-sided tooth') is a genus of Pliosaurs, which were large, carnivorous marine reptiles that lived during the Mid to Late Jurassic Period (c. 160 million to 155 million years ago (mya)). The only properly described species of this genus is Liopleurodon ferox, first identified by H.E Sauvage in 1873.

Four strong paddle-like limbs suggest that Liopleurodon was a powerful swimmer. Its four-flipper mode of propulsion is characteristic of all plesiosaurs. A study involving a swimming robot has demonstrated that although this form of propulsion is not especially efficient, it provides very good acceleration - a desirable character in a predator. Studies of the skull have showed that it could probably scan the water with its nostrils to ascertain the source of certain smells. Liopleurodon was carnivorous and it is unlikely that it had many, if any, predators.

Fossils of the creature have been found mainly in Germany, France, the former Soviet Union and the United Kingdom, from the Jurassic period, when Europe was covered by a large sea. The issue of its maximum size has been somewhat controversial. Most fossil evidence of Liopleurodon ferox seems to indicate that these beasts grew from 7 to 10 meters (23-33 feet long). However, as with its relative Kronosaurus, there is some uncertainty whether current reconstructions are correct. Fossil evidence from Great Britain indicates much larger contemporary pliosaurs, up to 15 metres (50 feet long) or even longer but the evidence is too fragmentary to determine whether the find belonged to Liopleurodon or to a species from some other genus.

In 2002, the discovery of a very large pliosaur in Mexico was announced. This came to be known as the 'Monster of Aramberri'. Conservative estimates gave a length of at least 15 metres, despite the possibility of its being a juvenile specimen. However, although widely reported as such, it did not belong to the Liopleurodon genus. Estimates of maximum size had already been circulated in the 1999 BBC documentary series Walking with Dinosaurs, where an enormous pliosaur was presented as a 25-meter-long Liopleurodon.

[edit] In popular culture

In the BBC's Walking with Dinosaurs and Sea Monsters, a Liopleurodon attacks and devours an Ophthalmosaurus, and a Eustreptospondylus before getting beached during a typhoon and suffocating under its own weight.