Camptosaurus dispar

Paleontologist Othniel Charles Marsh first described Camptosaurus dispar in 1885 based on fossils recovered from the Morrison Formation. Marsh, working at Yale University, was one of the most prolific dinosaur describers during the late 19th-century period known as the Bone Wars with his rival Edward Drinker Cope.

Camptosaurus dispar was a medium-sized, bipedal herbivore that lived during the Late Jurassic epoch. Its beak-like mouth and leaf-shaped teeth were well-adapted for stripping and processing plant material, likely including ferns, cycads, and conifers that were abundant in its ecosystem.

Fossils of Camptosaurus dispar have been discovered primarily in the Morrison Formation, a famous Late Jurassic geological formation spanning several western U.S. states including Wyoming, Utah, Colorado, and Oklahoma. The Morrison Formation is one of the richest sources of Late Jurassic dinosaur fossils in the world.

Camptosaurus is classified as an ornithopod, a group of beaked herbivorous dinosaurs that includes later and larger forms like Iguanodon and the duck-billed hadrosaurs. It is considered a relatively basal member of the group, predating many of the more specialized Cretaceous ornithopods by tens of millions of years.