The terrifying prehistoric 'sovereign of the sea'

The terrifying prehistoric 'sovereign of the sea' - with razor-sharp five inch teeth - Giant 28 foot long predator roamed seas that once covered Nevada - Named Thalattoarchon saurophagis - meaning 'lizard-eating sovereign of the sea'

A terrifying sea monster with five inch knife-edged teeth that roamed prehistoric Nevada almost 250 million years ago has been unveiled by scientists.

The giant predator was about 28 feet long (8.6 metres) in length and is the first top predator in marine food chains that would have fed on prey similar to its own size.

Its fossil described online in Proceedings of the National Academy of Sciences was dug out of rocks dating back 244 million years at a time when the Nevada desert where it was found was covered by a warm ocean.

Named Thalattoarchon saurophagis - meaning 'lizard-eating sovereign of the sea' - the sea creature had five inch teeth and was at the top of the food chain

Named Thalattoarchon saurophagis - meaning 'lizard-eating sovereign of the sea' - it's an early representative of the ichthyosaurs.

These were a group of marine reptiles that lived at the same time as dinosaurs and roamed the oceans for 160 million years.

During the middle Triassic Period, ichthyosaurs evolved from as yet unidentified land reptiles that moved back into the water, in a development parallel to that of the ancestors of modern-day dolphins and whales.

They were particularly abundant in the Jurassic Period, until they were replaced as the top aquatic predators by another reptilian order named plesiosaurs in the Cretaceous Period.

Thalattoarchon had a massive skull and jaws armed with large teeth with cutting edges used to seize and slice through other marine reptiles in the Triassic seas.

Because it was a meta-predator - capable of feeding on animals with bodies similar in size to its own - Thalattoarchon was comparable to modern orca whales.

A jaw full of five-inch, knife-edged teeth let this newly unearthed ichthyosaur tear into prey. The species swam in what is now Nevada.

Tooth crown of Thalattoarchon as seen in the field. The shape of the crown with its two cutting edges indicates that this ichthyosaur was a meat eater, not a fish eater.

Remarkably only eight million years prior to the appearance of Thalattoarchon, a severe extinction at the end of the Permian period killed as many as 80 to 96 percent of species in the Earth's oceans.

The rise of a predator such as Thalattoarchon documents the fast recovery and evolution of a modern ecosystem structure after the extinction.

Dr Nadia Frobisch, of the Humboldt Museum in Berlin, said: 'Everyday we learn more about the biodiversity of our planet including living and fossil species and their ecosystems.

'The new find characterises the establishment of a new and more advanced level of ecosystem structure.

'Findings like Thalattoarchon help us to understand the dynamics of our evolving planet and ultimately the impact humans have on today's environment.'

This is what the jaws of Thalattoarchon looked like when they were discovered by Field Museum preparator Jim Holstein on July 24, 1998.

Paleontologist Nadia Fröbisch preparing a plaster jacket for the fossil of the new ichthyosaur in the field in Nevada

The ichthyosaur was recovered from what is today a remote mountain range in central Nevada.

Most of the animal was preserved including the skull except the front of the snout, parts of the fins and the complete vertebral column up to the tip of the tail.

Supported by a grant from the National Geographic Society's Committee for Research and

Exploration, the team of paleontologists took three weeks to unearth the ichthyosaur in 2010 and prepare it for its transport by helicopter and truck out of the field.

Study co-author Dr Olivier Rieppel, of The Field Museum in Chicago, said: 'This discovery is a good example of how we study the past in order to illuminate the future.'

The back of the skull and neck during the excavation of the ichthyosaur skeleton in 2008. The bones are encased in a large nodule, the pieces of which were numbered for later reassembly.

A view down Favret Canyon with University of Bonn preparator Olaf Dülfer. The new ichthyosaur came from the beds in the background above the steep canyon walls.

This is the right side of the skull during preparation in the Field Museum labs showing the upturned eyeball and the huge teeth in front of it.

This article originally appeared in : The terrifying prehistoric 'sovereign of the sea' - with razor-sharp five inch teeth