Cumnoria

Cumnoria was a medium-sized early iguanodontian dinosaur that lived during the Late Jurassic period in what is now Oxfordshire, England. Known from a well-preserved partial skeleton found in a brick pit at Cumnor Hurst, it was historically classified as a European species of the North American genus Camptosaurus before being reinstated as a distinct genus. Measuring roughly three and a half metres in length, it was an agile herbivore capable of walking on all fours while browsing or shifting onto its robust hind legs to move quickly. Cumnoria possessed grinding teeth well adapted for chewing tough fern fronds, horsetails, and cycad leaves. It inhabited coastal lowlands and river floodplains, providing valuable insights into the dispersion and evolutionary transition of basal ornithopods across the Laurasian landmass during the Jurassic.

Discovered in an Oxfordshire brick pit, its skeleton was long referred to the American genus Camptosaurus.

Where and when

Cumnoria lived in the Late Jurassic, from 155.7 to 150.8 million years ago (Kimmeridgian age). Its remains come from United Kingdom, in the Kimmeridge Clay Formation.

The numbers

Length 3.8 m (estimates run from 3.5 to 4 m). Mass about 300 kg. Hip height about 1.2 m. That is 2.2 human-lengths, or 0.34 of a double-decker bus. These are estimates from partial skeleton; fields marked estimated by the site are length, mass, hip height.

Compare Cumnoria with a bus Place on the timeline