Regaliceratops

Regaliceratops was a massive horned dinosaur that lived in southwestern Alberta, Canada, during the late Maastrichtian stage of the Cretaceous. Measuring approximately five metres in length and weighing close to two tonnes, this formidable herbivore was similar in bulk to a modern hippopotamus. The type skull, nicknamed 'Hellboy' because of the immense difficulty palaeontologists experienced while chipping it out of extraordinarily hard limestone, shows striking evolutionary convergence. Although anatomically a chasmosaurine related to Triceratops, Regaliceratops had evolved a prominent, tall nose horn, tiny brow horns, and an elaborate halo of plate-like frill osteoderms resembling a crown, all traits typically seen in the older centrosaurine lineage which had already died out. This crown-like collar provided the inspiration for its genus name, which honours both its regal appearance and the Royal Tyrrell Museum where the preparation took nearly a decade.

Nicknamed 'Hellboy' due to the exceptionally hard rock surrounding its skull and its stubby brow horns.

Where and when

Regaliceratops lived in the Late Cretaceous, from 68.5 to 67.5 million years ago (Maastrichtian age). Its remains come from Canada, in the St. Mary River Formation.

The numbers

Length 5.3 m (estimates run from 5 to 5.5 m). Mass about 1.8 t. Hip height about 1.8 m. That is 3.1 human-lengths, or 0.47 of a double-decker bus. These are estimates from partial skeleton; fields marked estimated by the site are length, mass, hip height.

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