Category: Dinosaur

Plesiosuchus, Near Crocodile, was a giant and fully aquatic crocodyliform that lived in the seas around Late Jurassic England. In the Early Jurassic one group of crocodylomorphs, the Thalattosuchians, returned to the sea and flourished until the Early Cretaceous. They are commonly if inaccurately referred to as marine crocodiles.



Genera and Species

Classification: Crocodylomorpha,‭ ‬Thalattosuchia,‭ ‬Metriorhynchidae,‭ ‬Geosaurini. ‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬

Species: ‬ P.‭ ‬manselii.‬‬‬‬‬‬

Senior synonyms: Steneosaurus manselii


Plesiosuchus had a body shape that maximized swimming efficiency with a shark-like tail fin. Their forelimbs were small and paddle-like, and they had enlarged salt glands to cope with the chemistry of the oceans. They lost the osterderms, or boney armor, of modern crocodilians, thus streamlining their bodies. It was the largest known species of metriorhynchid. The skull was as large as that of Tyrannosaurus. Their teeth are similar to today's killer whales.


LENGTH: 5 – 7 m (15 – 35 ft.)

WEIGHT ? tons.


No eggs or nests have been discovered, like plesiosaurs or ichthyosaurs, which are known to give birth to live young out at sea. The marine lifestyle means that it is most likely that it mated at sea, but since no eggs or nests have been discovered, whether it gave birth to live young at sea like dolphins and ichthyosaurs or came ashore like turtles is not known. It was an apex predator, specialized in eating other marine reptiles, filling the same niche as Killer Whales do. Crocodiles are not known to be social but do provide some parenting so that is possible.

History of Discovery

It was discovered by Mansel-Pleydell, in the 1860s, with the remains of other large-bodied marine reptiles along the coast of Dorset. ‬‬


It was fully adapted to the marine realm, becoming pelagic in lifestyle and it shared the sea with other plesiosaurs, pliosaurs and ichthyosaurs.


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