A complete skeleton of the biggest marine reptile that ever existed has been unearthed in Mexico.

The fossilised bones have been identified as those of Liopleurodon ferox, a fierce predator that ruled the oceans about 150 million years ago.

GIANT SEA CREATURE

Type of animal: Plesiosaur (pliosaur) Food: Carnivore: snacked on smaller swimming reptiles Size: Up to 25 metres Weight: Up to 150 tonnes

The creature, which measures 20 metres (65 ft) from nose to tail, was discovered by German and Mexican palaeontologists.

It has been nicknamed the "Monster of Aramberri" after the site in northeastern Mexico where it was dug up.

Although many Liopleurodon remains have been unearthed before, none have been as complete as the Mexico discovery.

The bones are to be shipped to Germany for reconstruction at the Natural History Museum in Karlsruhe.

Scientists plan to use the skeleton to study how the monster of the deep lived and what it ate for its last meal.

Its remains were found along with those of smaller aquatic reptiles known as ichthyosaurs, which it may have snacked on.

Sea monster

The Liopleurodon was the master of the deep in prehistoric times.

The predator, the largest type of plesiosaur, was featured in the BBC Television series, Walking with Dinosaurs.

It had an impressive array of machete-sized teeth and jaws powerful enough to chew through granite.

Plesiosaurs appeared in the Early Jurassic period and rapidly split into two major groups: long-necked forms like the Cryptoclidus and short-necked forms, or plesiosaurs, like the Liopleurodon.

The marine reptiles are cousins of the dinosaurs that roamed the Earth between 208 million and 65 million years ago.

Their remains are relatively common and have been well preserved in several marine deposits throughout the world.