1.38" Champsosaurus Vertebrae (Cretaceous Reptile)

Here's a small tail vertebrae from the Cretaceous aged reptile Champsosaurus laramiensis. It was collected from private land in the Hell Creek formation, the same formation that is famous for producing fossils of T-Rex. The fossil has very little weathering.

Champsosaurus is an extinct genus of diapsid reptile belonging to the order Choristodera. It grew to about 1.50 m (5 ft) long, though C. gigas, the largest species, reached 3-3.5 m (10–12 ft) in length. Champsosaurus resembled a gharial and, like gharials, hunted in rivers and swamps, catching fish with its long, tooth-lined jaws. It probably swam with lateral body movements, pinning its limbs against its body to increase its streamline, just like crocodiles and the Marine Iguana. Behind the eyes Champsosaurus's skull was very wide as powerful jaw muscles were attached here.