Additional images

Jurassic monster!

Pliosaurs (short-necked plesiosaurs) were the top predators in the Jurassic seas. They had massive heads and throats, so could eat large prey, such as ichthyosaurs and marine crocodiles. They clamped their strong jaws around their victims, and twisted off hunks of flesh by rolling their whole body, just as crocodiles do today.

This enormous pliosaur forepaddle, from Pliosaurus macromerus, is an early find (1839) of John Mansel-Pleydell, one of the Dorset County Museum founders. It is among the largest and most complete ever found, and is particularly interesting as it is unusual to discover pliosaur remains in Kimmeridge Clay. With such paddles, pliosaur movement was akin to underwater flight.

The paddle is from an animal that would have been about the same size as the enormous skull recovered by Kevan Sheehan between 2004 and 2009 (also pictured).

Find out more on the reptiles page.

Common name


Scientific name

Pliosaurus macromerus


Vertebrates > Reptiles > Plesiosaurs


Kimmeridge Clay Formation

Time period

Upper Jurassic


152 million years

Where found


Found by

J C Mansel-Pleydell in 1839


Dorset County Museum, Dorchester

Accession number