Corythosaurus casuarius

Corythosaurus casuarius is a lambeosaurine hadrosaur from Alberta's Dinosaur Park Formation. Its tall semicircular crest contains paired nasal passages that loop through the crest before entering the airway, making it both a visual structure and a plausible acoustic resonator. Numerous skulls and skeletons reveal how the crest changed as animals grew. The celebrated holotype is an articulated skeleton with skin impressions and calcified tendons, providing unusually direct evidence for body outline as well as bone anatomy.

Its fossils occur between approximately 76.6 and 75.5 million years ago. Values shown here are approximate and reflect the current curated seed dataset.

AMNH 5240 preserves an articulated skeleton, skin impressions and a meshwork of calcified tendons that stiffened the back and tail. The hollow crest is formed chiefly by the nasal and premaxillary bones and houses elongated airways. Hundreds of tightly packed teeth formed dental batteries that replaced worn teeth continuously. Robust forelimbs and hoof-like finger bones supported quadrupedal walking, while longer hind limbs also permitted bipedal movement, especially during faster travel.

• Tall semicircular hollow crest containing looping nasal passages
• Dental batteries with continuously replaced grinding teeth
• Skin impressions preserved with the holotype
• Calcified tendons stiffening the back and tail
• Forelimbs suited to walking and longer hind limbs capable of bipedal movement

Barnum Brown and his American Museum field team collected the holotype beside Alberta's Red Deer River in 1912. Brown named Corythosaurus casuarius in 1914. Corythosaurus combines Greek korythos, helmet, with sauros, lizard; casuarius compares the crest with that of a cassowary. The original skeleton remains a prominent specimen in the American Museum of Natural History's Hall of Ornithischian Dinosaurs in New York.

Discovery credit: Barnum Brown, American Museum of Natural History field team.

Naming authors: Barnum Brown.

The Dinosaur Park Formation records river channels, coastal-plain floodplains, ponds and forested lowlands near the western shore of the Western Interior Seaway. Conifers, flowering plants, ferns and horsetails supplied diverse browse. Other hadrosaurs, horned dinosaurs, armoured dinosaurs and tyrannosaurids occur in the formation, but its fossil record spans many habitats and hundreds of thousands of years.

Dental batteries and a broad beak identify Corythosaurus as a plant eater able to crop and grind vegetation. The crest's internal passages could alter vocal resonance, and its conspicuous external shape likely also carried visual information. Models support acoustic potential but do not reveal a specific call. Differences among crest shapes once attributed to sex are now known to be strongly affected by growth and species identity.

• The holotype still preserves patches of the animal's skin outline.
• Its nasal passages travelled through the crest before reaching the throat.
• The American Museum displays the original 1912 skeleton on Floor 4.
• Young individuals had much smaller crests that expanded dramatically during growth.

A research repository is not necessarily a public exhibit. Loan and display status can change, so check with the institution before visiting.

1. 01
   Corythosaurus casuarius, a new crested dinosaur from the Belly River Cretaceous

   Barnum Brown · Bulletin of the American Museum of Natural History 33 · 1914

   Open source
2. 02
   Corythosaurus: Duck Billed Dinosaur Skeleton

   American Museum of Natural History

   Open source