Redondasaurus

One look at Redondasaurus, and you might think it's a crocodile. After all, it has a similar long, armored body, with a long snout and short legs. But this massive creature belonged to a group of reptiles called phytosaurs that went extinct millions of years before the first modern crocodiles appeared on Earth. However, phytosaurs and crocodiles do share a common ancestor, so you could say they're distant cousins.

Image credits: main image, Sean Murtha.