Tatenectes

Tatenectes had a very unusual body shape for a plesiosaur: its torso was flattened and boxy, and its belly ribs were thickened, which helped it stay stable in turbulent water.1

The first fossil of Tatenectes was described in 1900 by Wilbur Clinton Knight, who thought it was a species of Cimoliosaurus. That original specimen has since been lost.1

Tatenectes lived in the Sundance Sea, a shallow inland sea that was less than 40 meters (130 feet) deep and covered parts of western North America during the Jurassic.1

Its teeth were small and thin, with long roots and low enamel ridges, perfect for catching slippery prey like fish and squid.1

Tatenectes shared its sea home with other marine reptiles, including the plesiosaur Pantosaurus and the large pliosaur Megalneusaurus.1

Scientists think Tatenectes could have used lung deflation to help it dive, just like some modern sea turtles do.1