Saurolophus

Saurolophus osborni

Saurolophus (; meaning "lizard crest") is a genus of large hadrosaurid dinosaur that lived during the Late Cretaceous period of North America and Asia, in what is now the Horseshoe Canyon and Nemegt formations respectively (about 70 to 66 million years ago). It is one of the few dinosaur genera known from multiple continents. The type species, S. osborni, was described by Barnum Brown in 1912 from Canadian fossils. A second valid species, S. angustirostris, is represented by numerous specimens from Mongolia, and was described by Anatoly Konstantinovich Rozhdestvensky. Saurolophus is distinguished by a spike-like crest which projects up and back from the skull