New Species of Bus-Sized Prehistoric Sea Monster Discovered in Nevada

A new species of prehistoric sea monster has been unearthed in Nevada. Thalattoarchon saurophagis, which translates to "lizard eating sovereign of the sea", was at least 28 feet long and lived about 244 million years ago during the Triassic period.

Study co-author Nadia Fröbisch of Berlin's Museum of Natural History says that the sea monster fed on prey its own size, making it the first ocean predator that evolved to do so. The Thalattoarchon was an earl icthyosaur, which is part of a group of reptiles that roamed the world's seas during the dinosaur era.

The Thalattoarchon fossil was partially excavated in 1998, and was unusually well preserved, including the skull, fins, and entire vertebral column.

Fröbisch said

"It is pretty amazing, particularly for an animal this size."

On the last day of the 1998 expedition, the animal's fearsome teeth were briefly spotted. So in 2010, Fröbisch and her colleagues returned to the Nevada site to dig up the remainder of the fossil. While digging up the fossil, the researchers discovered an enormous skull and jaw filled with large, sharp teeth that are large enough to carve up other large marine reptiles.

The modern counterpart to the Thalattoarchon would be orcas and great white sharks, who also take on similar sized prey.

Fröbisch also says that the sea monster's discovery is also an excellent example of how ecosystems can bounce back from even the most extreme events:

"This animal occurs only eight million years after the biggest mass extinction event in Earth's history, the Permian extinction, which literally wiped out up to 95 percent of all the species in the ocean. The ocean was a pretty empty place afterward."

Fossil record shows that species returned quickly.

Despite thriving for some 160 million years, Thalattoarchon and its fellow icthyosaurs went extinct for unknown reasons. Fröbisch noted:

"Toward the end of the Cretaceous, they declined more and more, and their diversity also declined—and then they finally disappeared."

The study was published in the early electronic issue of the journal of the Proceedings of the National Academy of Sciences.