Temporal range: late Cretaceous
Chasmosaurus was a rhinoceros-like dinosaur, the order of bird-hipped, herbivorous dinosaurs. It was a member of the suborder Marginocephalia, and the family of large, horned, herding herbivores, the ceratopsians. Chasmosaurus was named by paleontologist Lawrence Lambe in 1914.
Chasmosaurus lived 65 to 100 million years ago and was 5 to 6 metres long with a weight of 3.6 tonnes.
They lived in western North America from Alaska to Mexico.