Jinzhousaurus

Jinzhousaurus was a large iguanodontian dinosaur belonging to the Early Cretaceous Jehol Biota of Liaoning Province, China. While the Jehol deposits are celebrated worldwide for small feathered theropods and primitive birds, Jinzhousaurus illustrates that sizeable herbivorous ornithopods also flourished alongside them. Measuring roughly seven metres in length, this substantial animal weighed over a tonne. It possessed a long, low skull with an expansive snout and a prominent toothless beak, backed by rows of grinding cheek teeth suitable for pulverising fibrous conifers, cycads, and ferns. Known from a nearly complete skeleton, Jinzhousaurus displays an anatomical mixture of primitive iguanodontian traits and progressive features that align it near the origins of the hadrosauroids. It walked predominantly on four legs when grazing but could rise onto its hind feet to flee fast-moving predators or reach higher tree foliage.

It was one of the largest dinosaurs to inhabit the famous Jehol Biota ecosystem of northeastern China.

Where and when

Jinzhousaurus lived in the Early Cretaceous, from 125 to 122 million years ago (Aptian age). Its remains come from China, in the Yixian Formation.

The numbers

Length 6.8 m (estimates run from 6.5 to 7 m). Mass about 1.5 t. Hip height about 2 m. That is 4 human-lengths, or 0.61 of a double-decker bus. These are estimates from near-complete skeleton; fields marked estimated by the site are length, mass, hip height.

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