PENTACERATOPS

genus of five-horned, large herbivorous dinosaurs found as fossils in North America and possibly eastern Asia and dating from the Late Cretaceous Period (97.5 to 66.4 million years ago). It was a relative of the more familiar Triceratops. Especially well known from the Kirtland Shale of New Mexico, Pentaceratops had one horn on its snout, one above each eye, and one on each side of the large, bony neck frill. The frill served as an attachment area for powerful muscles that aided in chewing and controlling movements of the head. It also protected vulnerable areas from attack by predators. The forelimbs of Pentaceratops were shorter than the hind limbs. The back had a characteristically arched appearance caused by the unequal development of the limbs. Pentaceratops was about 6 m (20 feet) long.