Saurolophus

Saurolophus was a large, successful duck-billed dinosaur that lived during the Late Cretaceous epoch. It is notable for its geographic distribution, with confirmed valid species discovered in both the Horseshoe Canyon Formation of Alberta and the Nemegt Formation of Mongolia. The Asian species, Saurolophus angustirostris, was especially gigantic, reaching lengths exceeding eleven metres. The hallmark feature of this genus is a solid, spike-like cranial crest pointing upward and backward from above the eyes. This crest supported a fleshy flap or inflatable nasal sac, which may have been used for visual communication or vocal display. Saurolophus browsed on tough vegetation using hundreds of self-sharpening teeth. Exceptional fossils including skin impressions show smooth, pebbled scales across the body and rowed hexagonal scales along the upper back.

It is one of the very few dinosaur genera documented by well-preserved species on both sides of the Pacific.

Where and when

Saurolophus lived in the Late Cretaceous, from 71 to 68.5 million years ago (Maastrichtian age). Its remains come from Canada and Mongolia, in the Horseshoe Canyon Formation.

The numbers

Length 10 m (estimates run from 8.5 to 12 m). Mass about 4.2 t. Hip height about 3.4 m. That is 5.9 human-lengths, or 0.89 of a double-decker bus. These are estimates from near-complete skeleton; fields marked estimated by the site are length, mass, hip height.

Compare Saurolophus with a bus Place on the timeline