Plesiosaurus

Plesiosaurus dolichodeirus · A sea reptile with a small head, a long slender neck, a broad turtle-like body and four long paddles.

It lived about 199.5 to 192.9 million years ago.

Plesiosaurus
Photo: DataBase Center for Life Science (DBCLS), CC BY 4.0
Plesiosaurus
Photo: Nobu Tamura (https://spinops.blogspot.com), CC BY 3.0
Plesiosaurus
Photo: Asteroiddave, CC BY 4.0

Taxonomy

KingdomAnimalia
PhylumChordata
ClassReptilia
OrderPlesiosauria
FamilyPlesiosauridae
GenusPlesiosaurus
SpeciesPlesiosaurus dolichodeirus

Where its fossils were found

England, mainly the Lias rocks of Dorset around Lyme Regis and the Bristol area.

Fun facts

  • Plesiosaurus had about 40 bones in its neck, and different fossils show anywhere from 38 to 42.
  • Plesiosaurus swam using its paddles, because its tail was too short to help much.
  • Plesiosaurus gave birth to live young in the water, like most sea snakes do.
  • Young Plesiosaurus might have lived in river mouths called estuaries before heading out into the open ocean.

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Facts and taxonomy adapted from Wikipedia (CC BY-SA 4.0).