Catutosaurus

Catutosaurus lived about 149 to 143 million years ago during the Late Jurassic period.2

Its fossils were found in the Vaca Muerta formation in Argentina, which is famous for its well-preserved marine reptiles.2

Catutosaurus had a mix of features: a skull like some ophthalmosaurids and a forefin like others, showing that these traits evolved separately.1

Its forefin had tightly packed polygonal bones and a broad connection between the upper arm and forearm bones.1

The name Catutosaurus comes from the Los Catutos area in Argentina where it was discovered.2

Catutosaurus is part of a group called ophthalmosaurids, which were the last ichthyosaurs to survive, living until about 94 million years ago.1