Biggest sea reptile discovered

27 February 2008

A 150-million-year-old sea reptile that grew to a massive 15m in length, has been discovered on an island in the Arctic, scientists announced today.

Nicknamed 'The monster', the creature was a pliosaur, a short-necked plesiosaur that lived in the world's oceans during the time of the dinosaurs.

'This is the first find of a significant portion of a whole skeleton of such a giant,' says Dr Angela Milner, palaeontologist (fossil expert) at the Natural History Museum. 'It will undoubtedly add much to our knowledge of these top marine predators.'

Arctic discovery

Norwegian scientists and volunteers from the University of Oslo Natural History Museum, discovered parts of the fossilised skeleton poking out of the side of a mountain on Spitsbergen, part of the Arctic island chain of Svalbard, in 2006.

On the look out for polar bears constantly, the team had to work through inhospitable arctic weather and by the end of the summer of 2007 they had finished their excavation.

Not only did they find a giant sea reptile, but they also uncovered parts of two other marine reptiles, a long-necked plesiosaur and an ichthyosaur.

Giant pliosaurs
Illustration by Tor Sponga of the giant sea reptile © Natural History Museum, University of Oslo, No

Illustration by Tor Sponga of the giant sea reptile © Natural History Museum, University of Oslo, Norway

They may have looked like dinosaurs, but pliosaurs were not: they were a group of plesiosaurs , extinct aquatic reptiles. Their short necks supported a huge skull full of an impressive set of teeth.  They had a teardrop-shaped body and two sets of powerful paddles to help them swim through the water.

As the top predators in the sea at the time, they would have preyed on squid-like animals, fish and other marine reptiles.

One of the largest pliosaurs known is the Australian Kronosaurus that grew up to 12m.

Dr Milner adds, 'Pliosaurs were reptiles and they were almost certainly not warm-blooded so this discovery is also a good demonstration of plate tectonics and ancient climates. 150 million years ago, Svalbard was not so near the North Pole, there was no ice cap and the climate was much warmer than it is today.'

The team continues the slow process of cleaning and conserving the bones collected and will carry out further research to see if this giant, and the other reptiles, are new species.