Clidastes

Clidastes was a mid sized marine predator from North American seaways in the Late Cretaceous, about 89 million years ago. It got up to 20 feet long, and was actually a large marine lizard rather than a dinosaur. It likely used its powerful jaws to hunt, and it’s smaller prehensile second jaws on the roof of its mouth to help it swallow its prey.