Platecarpus

Platecarpus is a type of mosasaur that lived during the Cretaceous Period.

Description
Platecarpus grew to about 4.3 meters in length, and the tail took up approximately half of this length. Unique among mosasaurs, it had a short skull and few teeth.

One speciemen in the Los Angeles County Museum (known as LACM 128319), shows a wealth of well-preserved features. These include retina tissue, respiratory tubes, skin impressions, and remnants of internal organs.

Classification
Platecarpus was a mosasaur, and was most closely related to Latoplatecarpus and Plesioplatecarpus. The genus has undergone a complex taxonomic history. Only one species, P. tympaniticus, is currently regarded as valid, but many other species have been named in the past.

History
Platecarpus was first discovered in Cretaceous deposits in Kansas. It was described in 1869 by Edward Drinker Cope. Since then, fragmentary fossils and one complete skull have been uncovered in the same area, as well as possible specimens from Belgium and Africa.

Diet
Like other mosasaurs, Platecarpus was a carnivore. It had much less robust teeth than other mosasaurs, however, and so likely fed on soft fish and squid.

Locomotion
It was first believed that Platecarpus and other mosasaurs moved their bodies from side to side like an eel while swimming, and that they had straight tails. In 2010, however, a specimen of Platecarpus was discovered with a fluked tail. This likely meant that it swam more like a shark and did not need to undulate its entire body.