Torosaurus

Torosaurus was a massive ceratopsian that shared the latest Cretaceous landscapes of North America with Tyrannosaurus rex right up until the end-Cretaceous extinction event. 8 metres in length. Its long, smooth frill contained two gigantic circular openings, distinguishing it anatomically from its famous contemporary Triceratops. While a prominent hypothesis once suggested that Torosaurus simply represented the fully mature growth stage of Triceratops, subsequent cranial and ontogenetic studies have reaffirmed that both are valid, distinct genera. Torosaurus possessed two long, forward-pointing brow horns and a stout nasal horn, which provided formidable defence against apex predators while browsing through dense woodlands.

8 metres in length.

Where and when

Torosaurus lived in the Late Cretaceous, from 68 to 66 million years ago (Maastrichtian age). Its remains come from United States and Canada, in the Hell Creek Formation.

The numbers

Length 7.8 m (estimates run from 7 to 8.5 m). Mass about 5.1 t. Hip height about 2.5 m. That is 4.6 human-lengths, or 0.7 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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