10 Terrifying Prehistoric Animals That Weren't Dinosaurs

Mosasaurus

A mosasaurus as depicted in Jurassic World.

Like plesiosaurs, mosasaurs were marine reptiles, and not technically dinosaurs. At almost 60 feet in length, mosasaurus was the biggest of the bunch.

In fact, it was one of the most dangerous creatures prowling the waters throughout the entire Cretaceous period. It looked like a massive crocodile (particularly the head), only equipped with fins, which — terrifyingly — allowed it better mobility in the water.

Thanks to the Discovery Channel, we can see what a mosasaur looks like when “upset”:

Next up: Paleontologists have called it the greatest apex predator of all time…

ncG1vNJzZmiZnKHBqa3TrKCnrJWnsrTAyKeeZ5ufony1sdGroJ%2BxmaO0brzRnp%2Biq6Skv6qvjJypnpmkqr%2Bmv45t