Pentaceratops

Pentaceratops is a genus of herbivorous ceratopsid dinosaur from the late Cretaceous Period of what is now North America.

Pentaceratops fossils were first discovered in 1921. The genus was named in 1923 when its type species Pentaceratops sternbergii was described. Pentaceratops lived around 76-73 million years ago, its remains having been mostly found in the Kirtland Formation in the San Juan Basin in New Mexico. Other dinosaurs which shared its habitat include Parasaurolophus cyrtocristatus, the pachycephalosaurSphaerotholus, the armored dinosaur Nodocephalosaurus and the tyrannosauroid Bistahieversor. About a dozen skulls and skeletons have been uncovered, so that most bones are known. One exceptionally large specimen later became its own genus, Titanoceratops, due to its more derived morphology closer to Triceratops and lack of unique characters shared with Pentaceratops proper, although the author that originally assigned it to Pentaceratops has decided to ignore this in subsequent publications.

Pentaceratops was about six meters (twenty feet) long, and has been estimated to have weighed around five tonnes. It had a short nose horn, two long brow horns, and long horns on the jugal bones. Its skull had a very long frill with triangular hornlets on the edge.