Scolosaurus

Scolosaurus was a heavily armored ankylosaurid dinosaur that inhabited ancient coastal wetlands during the Late Cretaceous in Alberta, Canada. Measuring up to six and a half metres long and weighing roughly two to three tonnes, it was a broad, quadrupedal plant-eater. The holotype skeleton, excavated in 1914 by William Cutler, is renowned for preserving a nearly intact coat of bony armour together with fossilised skin impressions. For many decades, Scolosaurus was regarded as a junior synonym of Euoplocephalus, but detailed anatomical reviews in the 2010s resurrected it as an independent genus. It is distinguished by small, conical spines on its cervical half-rings and circular osteoderms arranged across its back. Its tail ended in a heavy, kidney-shaped bony club capable of repelling large tyrannosaurs like Daspletosaurus.

The holotype specimen preserved a nearly complete, undisturbed armour cuirass along with extensive skin impressions.

Where and when

Scolosaurus lived in the Late Cretaceous, from 76.5 to 74.8 million years ago (Campanian age). Its remains come from Canada, in the Dinosaur Park Formation.

The numbers

Length 6 m (estimates run from 5.5 to 6.5 m). Mass about 2.4 t. Hip height about 1.6 m. That is 3.5 human-lengths, or 0.54 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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