Ceraunosaurus

Trinacromerum is an extinct genus of sauropterygian reptile, a member of the polycotylid plesiosaurs. It contains two species, T. bentonianum and T. kirki. Specimens have been discovered in the Late Cretaceous fossil deposits of what is now modern Kansas and Manitoba. Some fossils are also found in the Southern United States such as in the Mooreville Chalk of Alabama.