plesiosaur

fossil marine reptile

Also known as: Plesiosauri, Plesiosauria

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History

plesiosaur, (clade Plesiosauria), any of a group of long-necked marine reptiles found as fossils from the late Triassic Period into the late Cretaceous Period (215 million to 66 million years ago). Plesiosaurs had a wide distribution in European seas and around the Pacific Ocean, including Australia, North America, and Asia. Plesiosaurus, an early plesiosaur, was about 4.5 metres (15 feet) long, with a broad, flat body and a relatively short tail. It swam by flapping...

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