University Of Utah
Coahuilaceratops magnacuerna was a rhino-sized plant-eater belonging to a group called horned dinosaurs.

SALT LAKE CITY — Weighing in at 5 tons, standing 6 feet tall at its shoulders and sporting the longest horns of any species, this plant-eating dinosaur probably didn't have to worry about any predators.

The new species unearthed in Mexico is giving scientists fresh insight into the ancient history of western North America and will be unveiled next week in "New Perspectives on Horned Dinosaurs," a book to be released by Indiana University Press.

"We know very little about the dinosaurs of Mexico, and this find increases immeasurably our knowledge of the dinosaurs living in Mexico during the late Cretaceous," said Mark Loewen, a paleontologist with the Utah Museum of Natural History and lead author of the study.

The research team was led by paleontologists from the Utah Museum of Natural History at the University of Utah in a study partially funded by the National Geographic Society.

The 72-million-year-old, rhino-sized creature — Coahuilaceratops magnacuerna — was a 4- to 5-ton plant-eater belonging to a group called horned dinosaurs, or ceratopsids.

Coahuilaceratops was about 22 feet long as an adult, 6 feet to 7 feet tall at the shoulder and hips, with a 6-foot-long skull.

"Being one of the largest herbivores in its ecosystem, adult Coahuilaceratops probably didn't have to worry about large tyrannosaur predators," scientist Andrew Farke said.

Until recent years, there had been few large-scale paleontological projects in Mexico focused on dinosaurs that lived from 253 million to 65 million years ago, also known as the age of dinosaurs. This species is among the first dinosaurs from Mexico to be named.

Coahuilaceratops specimens are permanently housed in the collections of the Museum of the Desert in Saltillo, Mexico. Casts of the fossils are in the collections of the Utah Museum of Natural History in Salt Lake City.

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