Elasmosaurus - (pronounced eh-LAZZ-mo-SAWR-us)

Elasmosaurus (meaning: thin-plated lizard) had platelike bones in its pelvic girdle and was a plesiosaur with an extremely long neck that lived in the late Cretaceous period.

Elasmosaurus was a reptile, but not a dinosaur. They are distinguished by having two holes in the rear upper part of their skulls and two holes behind the eyes, like all Diapsids.

 

It was about 14 metres (46 feet) in length and weighed over 2,000 kg (2.2 tons), making it the longest ever plesiosaur species. It had a large body, a tiny head and four flippers for limbs.

More than half of its length was its neck, which had more than 70 vertebrae, more than any other animal. It had a small head with sharp teeth and most likely ate small bony fish such as belemnites (similar to squid), lepidotes and ammonites (molluscs). It swallowed small stones in order to aid its digestion.

Elasmosaurus lived in the open oceans and breathed air. Elasmosaurus swam slowly using its four paddle-like flippers in a manner similar to that of modern turtles. It may have been able to move a little bit on sandy shores, perhaps to lay its eggs.

Elasmosaurus lived during the late Cretaceous period and went extinct during the K-T mass extinction (65 million years ago).

Elasmosaurus was named by paleontologist E. D. Cope in 1868 (from a fossil was found in Wyoming, USA). Other Elasmosaurus fossils have also been found in North America.

Scientific Classification:

Kingdom: Animalia

Phylum: Chordata

Class: Reptilia

Order: Plesiosauria

Suborder: Plesiosauroidea

Family: Elasmosauridae

Genus: Elasmosaurus