Utah’s Cedar Mountain Formation has yielded two new species of iguanodont, cousins of the famous iguanodon, the plant-eating, beaked-mouthed dinosaur known for its ability to walk on its hind legs.
Working on federal land in two eastern Utah sites, teams led by the Utah Geological Survey discovered the two specimens in 2004. It took years of careful fieldwork to extract the bones, which include a nearly complete skull, and prepare them for study.
The most carefully dated of the two was discovered near Arches National Park by Andrew Milner, of the St. George Dinosaur Discovery Site. It was estimated to be 124 million years old and dubbed Hippodraco.
The survey’s Don DeBlieux discovered the other specimen near Green River. This one was dubbed Iguanacolossus.