Hadrosaurus
“bulky lizard”The first dinosaur skeleton ever mounted for the public, in Philadelphia in 1868
Overview
Hadrosaurus is a genus of hadrosaurid ornithopod dinosaurs that lived in North America during the Late Cretaceous Period in what is now the Woodbury Formation in New Jersey about 83.6 to 77.9 million years ago. The holotype specimen was found in fluvial marine sedimentation, meaning that the corpse of the animal was transported by a river and washed out to sea. Some fossils are found in the Tar Heel/Coachman Formation.
Source: Wikipedia
Why it matters
- Found in a New Jersey marl pit and described by Joseph Leidy in 1858 as the first reasonably complete dinosaur from North America.
- Its long hind legs and short arms were the first clear evidence that some dinosaurs walked on two legs.
- New Jersey made it the official state dinosaur in 1991.
Classification & discovery
- Group
- Dinosaur · Ornithopod · Hadrosauridae
- Parent taxon
- Brachylophosaurini
- Diet
- herbivore
- Environment
- terrestrial
- Life habit
- ground-dwelling, gregarious
- Named
- by Leidy in 1858
When it lived
85.7 – 66 million years ago · Santonian to Maastrichtian · Cretaceous
Where it was found
New Jersey, USA · Countries with fossils: CA, KZ, US
9 fossil occurrences in the Paleobiology Database · Rock formations: Eutaw, Frenchman, Marshalltown, Navesink, Oldman, Woodbury, Zhuravlevskaya
Size

Length 8 m · Mass 3 t · Size estimates are editorial, from the literature; silhouettes from PhyloPic.
- Length
- 8 m
- Height
- 3 m
- Mass
- 3 t3,000 kg
- First appearance
- 85.7 MaSantonian
- Last appearance
- 66 MaMaastrichtian
- Span of the fossil record
- 19.7 million years
- Fossil occurrences
- 9CA, KZ, US
- Year named
- 1858Leidy
Sources
Image: Jim, the Photographer from Springfield PA, United States of America, CC BY 2.0 · CC BY 2.0 · image page
Life restoration: Audrey.m.horn, CC BY-SA 4.0 · CC BY-SA 4.0 · image page
Silhouette: Will Toosey (PhyloPic) · license
Text: Wikipedia (CC BY-SA 4.0). Taglines, highlights and size estimates are editorial.