Cryopterygius

The name Cryopterygius means 'cold fin' or 'frozen fin' because it was found in frozen ground in a very cold place.1

Its skeleton was nearly complete and still joined together, which is very rare for an ichthyosaur fossil.1

Cryopterygius had 52 vertebrae in front of its hips, which is a lot for an ichthyosaur.1

Its upper arm bone, the humerus, had only two bumps at the end where it connected to the rest of the fin.1

It lived in the Late Jurassic, about 149 to 143 million years ago, in the cold polar seas.4

Scientists found a complete left hip and leg, which helped them understand how ichthyosaurs moved their hind fins.1