Arrhinoceratops

Arrhinoceratops was a mid-sized chasmosaurine ceratopsian known from the Horseshoe Canyon Formation along the Red Deer River in Alberta, Canada. 5 tonnes. When William Parks described the skull in 1925, he mistakenly concluded that the animal lacked a nasal horn, hence conferring its name which means no-nose-horn face; subsequent analysis confirmed it indeed possessed a short, blunt nose horn. In addition, Arrhinoceratops had two sharp, forward-pointing brow horns and a wide frill with small oval fenestrae. Its teeth were tightly arranged into powerful batteries suited for shearing tough, fibrous floodplain vegetation, representing an evolutionary intermediate between earlier Campanian chasmosaurines and late giants like Triceratops.

It was erroneously named 'no-nose-horn face' because its original describer believed it lacked a nasal horn.

Where and when

Arrhinoceratops lived in the Late Cretaceous, from 72 to 70 million years ago (Maastrichtian age). Its remains come from Canada, in the Horseshoe Canyon Formation.

The numbers

Length 5.3 m (estimates run from 4.5 to 6 m). Mass about 2.4 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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