A more than 30-year-long case of mistaken identity has been resolved.


- Ojoceratops, a new dinosaur, is a close relative of Triceratops.

- The dinosaur was mistaken for another species for more than 30 years.

- New pieces of a skull found in northern New Mexico settled the matter.

A new jumbo-sized genus and species of horned dinosaurs has been found in New Mexico.

The Ojoceratops fowleri is the apparent ancestor of the more famous and common Triceratops and Torosaurus that lived at the end of the reign of dinosaurs 65 to 70 million years ago.

The key to discovering the new species, pieces of which had been mistaken for a Torosaurus for more than 30 years, was fossil evidence of the frill on the beast's head, explain paleontologists.

"Ojoceratops is important because the horned dinosaurs (and indeed, all dinosaurs) have been so elusive," said paleontologist Andy Farke of the Alf Museum of Paleontology in Claremont, Calif. "We've only had bits and pieces up to this point, which has frustrated any attempts to determine how the animals in New Mexico at this time related to those from other parts of North America."

"We were all calling it Torosaurus for the horned dino that was known to have lived in the area," explained paleontologist Spencer Lucas of the New Mexico Museum of Natural History and Science in Albuquerque. Triceratops fossils have only been found further north, in Colorado and beyond, he said.

What was needed to clear up the matter were more pieces of the dinosaur's skull that revealed who this animal really was. Those were found in the summer of 2005 in the Bisti/De-na-zin Wilderness of northwest New Mexico by Denver Fowler, who is now a PhD student at Montana State University.

"What he found was this big honking bone in front of the frill," said Lucas. "We really had this breakthrough."

Lucas is the co-author of a paper officially describing Ojoceratops fowleri in the new book New Perspectives on Horned Dinosaurs. The lead author is paleontologist Robert Sullivan of the State Museum of Pennsylvania in Harrisburg.

When the new skull pieces were used to reconstruct the skull, what they had looked more like a Triceratops than a Torosaurus. However, the frill on the top of its skull was squared off, unlike a Triceratops.

"Although the Ojoceratops material doesn't represent a complete skull, there is definitely enough there to say what it is and how it's closely related to animals, such as Triceratops," said Farke. "Previously, nearly any scrappy fossil of a horned dinosaur from New Mexico had been referred to Torosaurus."

As to exactly how Ojoceratops is related to Triceratops, that's still open to debate.

"It's older," said Lucas. "It could be an ancestor of Triceratops. It might also be a southern species of Triceratops."