The Elasmosaurus was a large marine reptile that lived during the Late Cretaceous period (about 80 million years ago) in a shallow sea that once covered what is now central North America.

It belonged to a group of reptiles called plesiosaurs, which are characterized by:

• very long neck
• small head
• turtle-shaped body with flippers
• short tail

All these features are depicted in this Elasmosaurus toy.

The first Elasmosaurus fossil was described by the famous American paleontologist Edward Drinker Cope in 1868. Cope was an expert in lizard fossils and this led to an unusual mistake - while rushing to publish his description of Elasmosaurus, he placed the skull at the end of the tail, thinking it was the neck.

Cope spent a lot of time and money trying to buy back all the copies of his original description so he could correct his mistake and place the head in the right position.