Place

Camptosaurus aphanoecetes

A medium-sized two-legged dinosaur with a stripped tail.
Camptosaurus had a thumb spike, which most likely was not used for defense because of its small size

NPS Photo/Bob Walters Tess Kissinger

Quick Facts

Historical/Interpretive Information/Exhibits

Camptosaurus is a two-legged plant eating dinosaur. The beak-like front of the skull did not have teeth but was used to nip vegetation. Camptosaurus may have lived in small groups. It depended on its speed to escape predators. Camptosaurus is the ancestor of later large herbivores, such as iguanodonts, and duck bills.

Camptosaurus aphanoecetes is a species of ornithopod dinosaur from the Late Jurassic of North America, found in the Morrison Formation. Its bones are exposed on the quarry wall at Dinosaur National Monument.

Despite not having been found with a skull, the specimen from Dinosaur is the most complete Camptosaurus ever found. Like Camarasaurus it was on display for many years in the same block in which it was found. When the Carnegie remodeled their dinosaur exhibits, they decided to remove Camptosaurus from its stony prison to mount as a skeleton. Surprisingly, this specimen, which was identified as Camptosaurus medius for many years, was discovered to be an entirely new species in 2008.

Camptosaurus aphanoecetes is a new species of Camptosaurus, described by Ken Carpenter in 2008. The species name aphanoecetes comes from Greek aphanoe- meaning “hidden”, and -cetes, meaning “to dwell”. This name refers to the fact that a new species had been “hidden in plain sight” at the Carnegie Museum for over seventy-five years as a mounted skeleton.

Camptosaurus embryo was also found at Dinosaur. Although these bones were found without eggshell fragments, it has been identified as an embryo. The bones themselves are more fibrous in surface texture than those of the adult. Certain parts of the backbone on this specimen had not yet fused together as they are in adults. The Camptosaurus would probably have spinal cord damage when walking around if these bones never fused. These features are present in dinosaur embryos studied all over the world.

Dinosaur National Monument

Last updated: January 11, 2024