Another excellent fossil, brought to you from the Sternberg Museum of Natural History in Hays, Kansas:
This monster, about 29 feet (8.8 meters) long, is a mosasaur — to be specific, a Tylosaurus proriger. And it’s not even the biggest of its type. Tylosaurus proriger could grow to at least 49 feet (15 meters) in length, possibly more. They lived about 88 to 78 million years ago, and have been found worldwide (even in Antarctica). But the best specimens have come from the Niobara formation in the U.S. midwest — many of them in Kansas.
Tylosaurus‘ distinguishing characteristic is its snout (tylos comes from the Greek for “protuberance”), likely used to stun prey and possibly also used in inter-species combat. Based on preserved stomach contents, they ate pretty much anything that moved and was in or on the oceans of their day — fish, sharks, sea birds, marine reptiles, even other mosasaurs. Tylosaurs were the apex predators of the late Cretaceous seas, particularly the Western Interior Seaway that once covered the central part of what’s now the United States and Canada.