Edmontosaurus regalis

Edmontosaurus regalis Temporal range: Late Cretaceous, 73–70 Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
Holotype skeleton of Thespesius edmontoni, now thought to be a young E. regalis
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Clade:	Dinosauria
Clade:	†Ornithischia
Clade:	†Neornithischia
Clade:	†Ornithopoda
Family:	†Hadrosauridae
Subfamily:	†Saurolophinae
Genus:	†Edmontosaurus
Species:	†E. regalis
Binomial name
†Edmontosaurus regalis Lambe, 1917
Synonyms
Trachodon avatus Cope, 1871 Thespesius edmontoni Gilmore, 1924 Anatosaurus edmontoni (Gilmore, 1924) Lull & Wright, 1942 Edmontosaurus edmontoni (Gilmore, 1924) Russell and Chamney, 1967 Thespesius edmontonensis Gilmore, 1924 emend Olshevsky, 1991

Edmontosaurus regalis is a species of comb-crested hadrosaurid dinosaur. Fossils of E. regalis have been found in rocks of western North America that date from the late Campanian age of the Cretaceous Period 73 million years ago, but it may have possibly lived into the early Maastrichtian.^[1]

E. regalis was one of the largest hadrosaurids, measuring up to 12 metres (39 ft) long and weighing around 4.0 metric tons (4.4 short tons). It is classified as a genus of saurolophine (or hadrosaurine) hadrosaurid, a member of the group of hadrosaurids that lacked large, hollow crests, and instead had smaller, solid crests or fleshy combs.^[2] The distribution of E. regalis fossils suggests that it preferred coasts and coastal plains. It was a herbivore that could move on both two legs and four. Because it is known from several bone beds, E. regalis is thought to have lived in large groups. The wealth of fossils has allowed researchers to study its paleobiology in detail, including its brain, how it may have fed, and its injuries and pathologies.