Scientists have identified a new species of extinct reptiles – 12 to 18 feet long carnivores related to crocodiles – that lived 212 million years ago in US.
The fossils of the reptile named Vivaron haydeni was found in Ghost Ranch of New Mexico during an excavation in 2009, co-led by Sterling Nesbitt, who was at University of Texas at Austin in the US during the research.
Vivaron haydeni is named for a famed, monstrous snake – 30 feet long – of Ghost Ranch lore, a story passed around campfires more than a century ago.
The fossil represents the sixth species of rauisuchid found thus far, and the second found in what is now the American Southwest, but was once part of the western portion of the supercontinent Pangea.
Vivaron was a carnivorous archosaur – a large set of animals that includes crocodilians and dinosaurs, as mammals includes humans and dogs.
Vivaron itself measured 12 to 18 feet long, and walked on four legs. Thus far, three jaw bones, other skull fragments, and hip-bones from at least three individuals – two large, one smaller – have been found.
“These were some of the biggest predators at the time, all dinosaurs were much smaller,” said Nesbitt, now an assistant professor of geosciences at Virginia Tech, speaking of the Triassic Period, more than 200 million years ago.
Vivaron is distinguishable by its upper jaw bone, which is smoother in appearance than other rauisuchid species. Other features of the animal must be inferred from close relatives.
“It is possible that other bones were not preserved, were previously collected, or are still in the ground,” said Emily Lessner from the Virginia Tech College of Science.
“Initially, I cleaned fossils in the lab and worked on a project reconstructing soft tissue structures using computed tomographic, or CT, scans on the computer,” said Lessner.
“When you look at anything so long, so close, you realise extra details and patterns you would not otherwise notice,” she added.