Fossil of giant prehistoric sea creature that ruled the ocean in the age of dinosaurs discovered

A fossil of a previously unknown species of aquatic reptile the size of a bus has been discovered by scientists in Russia.

A type of pliosaur, its head alone was about 1.5 metres (nearly five feet) long with most of this made up of a slender beak-like structure similar to ones seen today on some river dolphins.

The fossil was found in 2002 on the bank of the Volga river near the city of Ulyanovsk, but it has only now been identified as a new species. It has been named Luskhan itilensis, meaning “Master spirit from the Volga”.

Pliosaurs belong to the plesiosaur family which were not actually dinosaurs but lived alongside them during the Jurassic period, when they were among the top predators. They had an unusual body shape with four large flippers, a stiff torso and a neck of varying length.

The slenderness of the new species’ beak or rostrum changes scientists’ understanding of the evolution of pliosaurs. Dr Valentin Fischer, a lecturer at Liège University in Belgium and lead author of a paper in the journal Current Biology, said: “This is the most striking feature, as it suggests that pliosaurs colonised a much wider range of ecological niches than previously assumed.”

The pliosaurs lived for about 135 million years, through a major extinction event about 145 million years ago, but then succumbed long before the mass extinction of the dinosaurs 66 million years ago.

The new species was not the largest of the pliosaurs. A fossil of a two-metre-long head of a Pliosaurus kevani was gradually unearthed by café owner Kevan Sheehan from the foot of a cliff on the Jurassic Coast of Dorset, it was revealed in 2009. The entire animal is thought to have been about 15 metres (50ft) long.

Another pliosaur, found in 2008 on the Arctic island of Svalbard, was estimated to have a bite-force of 33,000lbs per square inch – 11 times that of Tyrannosaurus rex and 13 times the force exerted by a modern-day alligator.