Platypelta

Platypelta was a medium-sized armoured ankylosaurid that lived during the Late Cretaceous in what is now Alberta, Canada. Originally collected in 1914 by Charles Hazelius Sternberg, its fossils were long lumped together with the familiar genus Euoplocephalus. Detailed restudy in 2018 revealed that its distinctive flat, broad osteoderms, keeled tail club, and subtle skull characteristics justified separation as a distinct genus. Measuring roughly six metres in length, it was heavily built and broad-bodied, walking on four robust legs. As a low-browsing herbivore, Platypelta consumed ferns, cycads, and flowering shrubs, processing plant matter in a barrel-shaped digestive tract. Its head bore triangular horns, while heavy bands of bony armour shielded its neck, back, and hips from predatory tyrannosaurids.

It was long regarded as a specimen of Euoplocephalus until differences in osteoderm morphology revived its distinction.

Where and when

Platypelta lived in the Late Cretaceous, from 77.5 to 75 million years ago (Campanian age). Its remains come from Canada, in the Dinosaur Park Formation.

The numbers

Length 5.8 m (estimates run from 5.5 to 6 m). Mass about 2.2 t. Hip height about 1.5 m. That is 3.4 human-lengths, or 0.52 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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