Elasmosaurus

Elasmosaurus platyurus · Elasmosaurus was a long-necked marine reptile called a plesiosaur that lived in North America during the Late Cretaceous period.

It lived about 80.6 to 77 million years ago.

Elasmosaurus
Photo: Dmitry Bogdanov, CC BY-SA 4.0
Elasmosaurus
Photo: Corbin Rainbolt, CC BY 4.0
Elasmosaurus
Photo: Nobu Tamura (http://spinops.blogspot.com), CC BY 2.5

Taxonomy

KingdomAnimalia
PhylumChordata
ClassReptilia
OrderPlesiosauria
FamilyElasmosauridae
GenusElasmosaurus
SpeciesElasmosaurus platyurus

Where its fossils were found

Kansas, USA (Pierre Shale); a fragment from Germany may also belong to it.

Fun facts

  • Elasmosaurus had 72 neck vertebrae, more than any other plesiosaur except its relative Albertonectes.
  • The first scientist to reconstruct its skeleton put the skull at the end of the tail, a mistake that fueled the famous "Bone Wars" rivalry.
  • Despite old pictures of swan-like necks, Elasmosaurus could not lift its neck high above the water because it was not very flexible.
  • Its paddles were so rigid that plesiosaurs could not come ashore to lay eggs, so they probably gave birth to live young like some sea snakes.

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