Prehistoric Animals


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Liopleurodon is a marine reptile from the Mesozoic era, more specifically a pliosaur, which became known and gain popularity with its appearance in the British documentary series Walking With Dinosaurs. In the documentary, Liopleurodon is portrayed as a sea monster reaching 80 feet in length; this is a gross exaggeration since in reality this pliosaur was quite a bit smaller at about 30 feet long, twice the size of a large adult white shark. Producers of the series have extrapolated from the skull of the beast, which is a serious mistake in the case of pliosaurs since their heads are disproportionate relative to the rest of their bodies.

Liopleurodon is the perfect example of a pliosaur: a long flattened skull, a relatively short neck and long fins that attached to a thick torso, all ending with a small tail. By comparison, plesiosaurs (often considered aquatic sauropods) usually have a small head and a very elongated neck, a more hydrodynamic body shape and a milder temperament.

First discoveries

The first vestiges of Liopleurodon were found towards the end of the 19th century, in 1873, in a small town in France. The researchers found 3 teeth, each measuring nearly 3 inches long and having a smooth surface that is also the origin of the name of this marine reptile: "smooth-sided teeth".

One immediately wonders how the fossilized teeth of a marine creature could be found in France. At the time of the Upper Jurassic, about 160 million years ago, a vast majority of present-day Western Europe was covered with a shallow oceanic layer where plesiosaurs and pliosaurs freely swam.

The Upper Jurassic apex predator

Pliosaurs are known to be extremely fierce and dangerous, real hunting machines like the great white shark. And judging by the size of the beast, which could reach 10 tons at full adult potential, one quickly comes to the conclusion that Liopleurodon was to reign supreme and king in the marine ecosystems of that time, relentlessly swallowing fish, squid and other small aquatic reptiles.

With its four long paddle-shaped fins, Liopleurodon could propel itself into the water at considerable speeds - albeit less quickly than the great whites - and reach peaks when the needs of the hunt required it.

In addition, this pliosaur had the nostrils well forward on the muzzle which gave it a well developed sense of smell and allowed it to locate preys over long distances. Liopleurodon funneled water in its nostrils to detect the chemical secretions of its future meals.

Like whales and dolphins, the pliosaurs and more generally the plesiosaurs did not have gills and had to frequently rise to the surface in order to breathe.

Along with Kronosaurus and Pliosaurus, Liopleurodon is one of the largest specimens of pliosaurs to have existed during the Jurassic period.

The star of Charlie the Unicorn

In an absolutely silly viral video on YouTube, three mentally deficient unicorns en route to "Candy Mountain" meet a Liopleurodon resting in the middle of the forest. Charlie finds himself locked up in the candy cellar and has a kidney pulled out. The trilogy of Charlie the Unicorn has accumulated tens of millions of views and propel Liopleurodon to the rank of superstar.

Fast extinction

Pliosaurs were formidable oceanic predators but were no match for the progress of evolution. At the beginning of the Cretaceous period, mosasaurs, a new species of large, smooth, vicious marine reptile, began to supplant pliosaurs for ocean dominance. The mosasaurs were subsequently supplanted themselves by prehistoric sharks better adapted to the changing conditions of the time.

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