Paper describes new dinosaur species found near Choteau, Montana (9/21/2007)

Gerry Ohrstrom, left, and Dave Sands, watch Nels Peterson, left, and John Scannella excavate a dinosaur near MSU's Osh Camp in Mongolia. It was even more primitive than the new species described this month from Choteau. (Photo courtesy of Jack Horner).(Photo courtesy of Jack Horner).

A dinosaur skeleton found 24 years ago near Choteau has finally been identified as a new species that links North American dinosaurs with Asian dinosaurs. The dinosaur would have weighed 30 to 40 pounds, walked on two feet and stood about three feet tall. The fossil came from sediment that's about 80 million years old.

A paper on the finding was published in September's issue of the Journal of Vertebrate Paleontology, co-author Jack Horner said Friday after returning from Mongolia where he and his crew found 80 dinosaurs in a week. Horner is curator of paleontology at Montana State University's Museum of the Rockies. The paper's lead author was Brenda Chinnery, a former postdoctoral researcher with Horner.

Horner said he found the nearly-complete skeleton in 1983, but it was located in extremely hard rock and took a long time to prepare. He also had to wait about two decades before he found an expert who could identify it. That expert was Chinnery, who specializes in horned dinosaurs. Chinnery had worked for one of Horner's colleagues at Johns Hopkins University and then came to MSU. She left MSU about two years ago and is now a paleontologist at the University of Texas.

"I knew it was probably a new dinosaur, but it took someone that really knew what they were doing to be able to describe it," Horner said.

The dinosaur fossil has been stored in the Museum of the Rockies since its discovery, but it will be displayed this winter, Horner said. The skeleton has a reddish tinge because some of the original bone was replaced by jasper. It dates to the early part of the Late Cretaceous Period.

The dinosaur, nicknamed Cera, was named Cerasinops hodgskissi after landowner Wilson Hodgskiss. who gave him permission to collect the skeleton for the Museum of the Rockies, Horner said. The fossil was found south of Choteau, in a different area than the famed Egg Mountain site.

The C. hodgskissi is such a simple specimen that it's hard to describe in terms of distinguishing characteristics, Horner said. Tests, however, showed that it represents a very primitive species that shares characteristics of Neo-ceratopsian dinosaurs in North America and Asia. Ceratopsian dinosaurs have horns, but these do not.

Chinnery said, "Cerasinops is exciting because of the traits that she has - some are known only from Asian horned dinosaurs and others are known only from North American groups. For example, some Asian groups have extra teeth at the front of the jaw, but until now, this has never been found in a North American horned dinosaur. On the other hand, Cerasinops shares a unique way of chewing food with the other North American groups."

Horner said he was looking at even more primitive dinosaurs on his recent trip to Mongolia. His team collected more than 80 skeletons, with 70 of them coming from one site. Last year, they collected 67 skeletons at the same site. The Mongolian project is a joint research project between MSU and Mongolia's Science and Technology University.

Note: This story has been adapted from a news release issued by Montana State University

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