Image by Nobu Tamura · CC BY-SA 3.0 · View on Wikimedia Commons
Another reptile groupPlesiosaurCarnivore
Elasmosaurus
Elasmosaurus was a long-necked plesiosaur of the Late Cretaceous from Kansas, USA. Its neck made up more than half of its total length.
Who it is related to: Part of the Sauropterygia, a branch of reptiles separate from the dinosaurs.
Fun facts
- When Edward Drinker Cope described the first skeleton in 1868, he put the head on the end of the tail; Joseph Leidy pointed out the mistake.
- The episode became part of the "Bone Wars", Cope's fossil-hunting rivalry with Othniel Marsh.
- The neck could not hold the head high out of the water like a swan's, so old pictures drawn that way are wrong.
Dinosaurs from the same rocks
Elasmosaurus was found in the Pierre Shale, which also holds these dinosaurs: the same region and broad span of time.
Formation data from the Paleobiology Database, counting only each genus's main formations. One formation can span hundreds of thousands to millions of years, so this doesn't mean any two of them ever met.
Scientific details
- Group
- Plesiosaurs
- Family
- Elasmosauridae
- When it lived
- 72.2–93.9 million years ago
- Geologic stages
- Turonian – Campanian
- Named by
- Cope, 1868
- Fossil occurrences
- 9 sites
Countries with fossils
- Japan
- United States
Sources for the description and facts
Data from Paleobiology Database and Wikidata