Large marine squamate reptile
Mosasaurus
This is Mosasaurus, a huge sea reptile that lived during the Late Cretaceous. It was not a dinosaur.
Look at its flippers and powerful tail. Can you imagine its tail pushing it forwards while the flippers steer?
Explore it in the 3D museum →
Meet this animal
- When it lived
- Late Cretaceous (about 82 million to 66 million years ago)
- Fossil discovery regions
- Europe, North America, Other Late Cretaceous seas
- Size
- 10–14 metres
- Diet
- Meat-eater
- Classification
- Large marine squamate reptile
Mosasaurus was not a dinosaur. It was a fully aquatic squamate reptile, on the branch of the family tree that also includes today's lizards and snakes. Its flippers helped it steer, while its tail provided most of the thrust. Soft-tissue evidence from other well-preserved mosasaurs supports a tail tip with an asymmetrical, two-lobed outline.
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