Archives of The Cold Blooded News

The Newsletter of the Colorado Herpetological Society

Volume 32, Number 1;   January, 2005

Trematopid Amphibian Fossil a New Genus

Pittsburgh - The discovery of a fossil in a fresh road cut near Pittsburgh International Airport is a story of serendipity. During a field trip for a freshman geology class at the University of Pittsburgh, a student picked up the softball-sized fossil, thought it of little interest and threw it aside. The same student saw the fossil during the walk back, but this time he showed it to class lecturer Charles Jones, who said he saw the teeth first and then the outline of a skull. "It was immediately clear that this was rare," Jones said. Paleontologists with the Carnegie Museum of Natural History were stunned when the impeccably preserved fossil from a trematopid amphibian turned up in their own back yard. The discovery has set off a hunt for bigger finds that could help define a gray area in the Earth's history in what is now the northeast United States.

When Carnegie paleontologist Dave Berman saw the stone-encased skull fossil, he knew exactly what it was. There are only two other known fossils of the same family and he found one of them more than a decade ago in New Mexico. Paleontologists say the find is a new genus and a new species. The rock encasing the fossil has been carefully chipped away by Berman and his team, revealing a boxy skull slightly larger than that of a large cat, but with a wicked set of choppers. The cheeks are roughly at right angles to the top of the skull and there are long rows of spiky teeth along with three sets of "tusks" lining the roof of the mouth.

"It's a new species without a name yet," said Christopher Beard, curator of vertebrate paleontology at the Carnegie. "It's new to science, but we know it belongs to fairly terrestrial adapted amphibians living in the Pennsylvanian Period, about 300 million years ago."

The species has some characteristics of a crocodile, but is closer to a massive salamander - one that could tear its prey to shreds, said Berman, who is leading the research team. Berman has written extensively on this family of amphibians since he found a similar fossil in north central New Mexico. But the most recent discovery may have substantially altered what scientists know, or thought they knew. "This is much more advanced, meaning that they first appeared even further back then we had thought, perhaps another five or 10 million years, but that's still a guess right now," Berman said.

The Pittsburgh region is not considered a hotbed for vertebrate finds. Fossils of substance are rarely found in the Northeast due to lush forests and vegetation. Paleontologists will fan out across the area where the skull fossil was found in the coming months as vegetation dies off, looking for the rest of the body, and possibly more. "It was a lucky shot that kid found the fossil for sure, but at the same time the road construction in that area has revealed ancient layers of rock," Beard said. "It is now an optimal time to go back out. Ideally we may be able to reconstruct the entire ecosystem, plant and animal life of 300 million years ago, which right now is a matter of vagaries."

Talks are underway about what to call the fossil, starting with "striegeli," after the student who found it, Adam Sriegel.