"The animal would have been so massive that I think it would have been able to prey effectively on anything that was ...

Geologists working on surveying land in Mississippi stumbled upon an incredible find: the fossil of an ancient marine apex predator considered a "sea dragon" of the time.

It was capable of growing beyond 30 feet in length and weighed around 10 tons—a mature elephant plus a sedan car.

I was quite pleased with my day: I found some pliosaur ... including a number of jaw and skull sections. Also there were no other creatures of that size in the Jurassic seas at that time.

The discovered vertebra, potentially the largest found in Mississippi ... from the mud along a creek they realized it was from a sea monster known as a mosasaur and the size of it shocked them.