Scientists Uncover New Species of Ancient Vertebrate

A team of vertebrate paleontologists have recently described a previously unknown prehistoric amphibian, Kryostega collinsoni. The animal is estimated to have lived about 240 million years ago in Antarctica and belongs to a diverse group of prehistoric animals known as the temnospondyli—semi-aquatic animals that resembled large salamanders or crocodiles.

Kryostega is thought to have been about 15 feet in length. It is estimated to have had a large skull about 2.75 feet long and 2 feet at its widest point (the estimates of the animal's size were made based on the size of its nostril, which was present in the fossil skull piece). It had large upper and lower teeth along the edge of its mouth and a set of teeth on the roof of its mouth. According to Christian Sidor, Kryostega was the largest known animal in Antarctica during the Triassic. He goes on to add:

"Its teeth, compared to other amphibians were just enormous. It leads us to believe this animal was a predator taking down large prey."

At the time Kryostega was alive, Antarctica was a warmer place. It was part of the supercontinent Pangea, and was nestled against the land that was to become Africa. The particular region of Antarctica where Kryostega was found was, 240 million years ago, near what is today South Africa's Karoo Basin, one of the richest fossil depositories in the world.

The description of Kryostega is based on a fossilized section of the animal's snout that was discovered in 1986 by Dr. William Hammer of Augustana College. Hammer unearthed the remains from a study site in Antarctica. At that time, Hammer also collected a large number of other fossils, so the Kryostega fossil remained unstudied until recently. Now, a full description of the new species is available in the September issue of the Journal of Vertebrate Paleontology. The paper is authored by Hammer and two other vertebrate paleontologists, Christian Sidor of the Univiersity of Washington and Ross Damiani of Staatliches Museum fur Naturkunde Stuttgart, Germany.

Find out more: Extinct Species Had Large Teeth on Roof of Mouth (Eurekalert)

Photo © Christian Sidor / University of Washington. This fossil of a new temnospondyl species, Kryostega collinsoni, shows teeth along the edge of the skull and spaced out across the palate roof, about one-third of the way up in the photograph.