Corythosaurus

Phylogeny: Dinosauria > Ornithischia > Genasauria > Neornithischia > Cerapoda > Ornithopoda > Iguanodontia > Ankylopollexia > Styracosterna > Hadrosauriformes > Hadrosauroidea > Hadrosauridae > Lambeosaurinae > Lambeosaurini

Overview: Corythosaurus is one of the better known examples of the Lambeosaurinae – one of the two major lineages of “duck-billed” hadrosaurids. Lambeosaurines are probably best known for the flamboyant, bony crests they often sported atop their heads or snouts. Corythosaurus possessed such a crest, taking the form of a tall, rounded lobe. The crests of lambeosaurines were usually hollow and interlinked with the animal’s respiratory system, which could imply they used them as resonating chambers to make loud calls. Such vocalizations could’ve been used to alert others in the herd of approaching danger or for courtship purposes. The bony core we see on the fossils are also likely not the full extent of the crest itself. In life, a horn-like coating of keratin probably extended out from it. This keratin may’ve been brightly colored or patterned, which was itself also useful for courtship, to signal health and vitality. Other explanations for both the calls and the form of the crest could’ve included species recognition, as Corythosaurus very likely coexisted with a few other hadrosaurs, including other lamboesaurines like Lambeosaurus itself.

The holotype specimen of Corythosaurus was found in the early 1910’s by the renowned American fossil hunter Barnum Brown, in the Canadian province of Alberta. It consisted of a mostly complete skeleton with associated skin impressions, showing a mosaic of non-overlapping scales. Described in 1914, Brown would name it the “helmeted lizard”, specifically drawing from the name of helmets worn by Corinthian hoplites in Ancient Greece. The name of the species, Corythosaurus casuarius, refers to modern cassowary birds, which have similar head crests. Brown found its remains within the Dinosaur Park Formation, though other specimens would be found in the Oldman Formation, as well as the Judith River Formation in Montana. Corythosaurus lived alongside other dinosaurs such as Lambeosaurus, Parasaurolophus, Euoplocephalus, Edmontonia, Centrosaurus, Chasmosaurus, and a few large tyrannosaurs like Daspletosaurus or Gorgosaurus. Corythosaurus was likely a source of food for the latter genera. It itself would’ve eaten mainly low-level vegetation like ferns or some early flowering plants, though it could also reach low branches by walking on its hind legs.