Corythosaurus

Corythosaurus Temporal range: Late Cretaceous (Campanian), 77–75.7 Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
Skeleton in Carnegie Museum
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Clade:	Dinosauria
Clade:	†Ornithischia
Clade:	†Neornithischia
Clade:	†Ornithopoda
Family:	†Hadrosauridae
Subfamily:	†Lambeosaurinae
Tribe:	†Lambeosaurini
Genus:	†Corythosaurus Brown, 1914
Type species
†Corythosaurus casuarius Brown, 1914
Species
†C. casuarius Brown, 1914 (type) †C. intermedius (Parks, 1923 [originally Stephanosaurus])
Synonyms
List Corythosaurus excavatus Gilmore, 1923 Stephanosaurus intermedius Parks, 1923 Procheneosaurus erectofrons (Parks, 1931 [originally Tetragonosaurus]) Tetragonosaurus erectofrons Parks, 1931 Corythosaurus bicristatus Parks, 1935 Corythosaurus brevicristatus Parks, 1935

Corythosaurus (/kəˌrɪθəˈsɔːrəs/;^[1] lit. 'helmeted lizard') is a genus of hadrosaurid "duck-billed" dinosaur from the Late Cretaceous period, about 77–75.7 million years ago, in what is now western North America. Its name is derived from the Greek word κόρυς, meaning "helmet", named and described in 1914 by Barnum Brown. Corythosaurus is now thought to be a lambeosaurine, thus related to Lambeosaurus, Nipponosaurus, Velafrons, Hypacrosaurus, and Olorotitan. Corythosaurus has an estimated length of 7.7–9 metres (25–30 ft) and has a skull, including the crest, that is 70.8 centimetres (27.9 in; 2.32 ft) tall.

Corythosaurus is known from many complete specimens, including the nearly complete holotype found by Brown in 1911. The holotype skeleton is only missing the last section of the tail and part of the front legs, but was preserved with impressions of polygonal scales. Corythosaurus is known from many skulls with tall crests that resemble those of the cassowary and a Corinthian helmet. The most likely function of the crest is thought to be vocalization. As in a trombone, sound waves would travel through many chambers in the crest and then get amplified when Corythosaurus exhaled. One Corythosaurus specimen has even been preserved with its last meal in its chest cavity. Inside the cavity were remains of conifer needles, seeds, twigs, and fruits, suggesting that Corythosaurus probably fed on all of these.^[2]

The two species of Corythosaurus are both present in slightly different levels of the Dinosaur Park Formation. Both still co-existed with theropods and other ornithischians, like Daspletosaurus, Brachylophosaurus, Parasaurolophus, Scolosaurus, and Chasmosaurus.