But it was impossible to tell exactly what kind of dinosaur it was when paleontologist Jack Horner first found its fossil skeleton near the town of Choteau in 1983 (see Montana map).
"I discovered this skeleton 24 years ago after sitting on it having lunch," said Horner, curator of paleontology at Montana State University's Museum of the Rockies, by email.
"It was preserved in reddish rock and was very difficult to see in the rock."
After a team of experts prepared—or removed rock from—the fossil, the dino's distinct features began to take shape, Horner said.
But it would be decades before scientists knew enough about so-called protoceratopsians to find the animal's place in the dinosaur family tree.
"I knew when it was prepared that it was probably a new species, but there weren't any researchers at that time that focused on protoceratopsians," Horner said.
"So the specimen waited for 24 years before someone—Brenda—came along that could do the specimen justice."
Cerasinops's fossil skeleton, flecked with red from deposits of jasper trapped in the bones, will go on display at the Museum of the Rockies in Bozeman this winter, Horner added.
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