Add Yahoo as a preferred source to see more of our stories on Google. A single tooth found among dinosaur bones in North Dakota reveals that some of the largest sea reptiles also ruled ancient rivers.

Scientists have discovered a new species of mosasaur, large, carnivorous aquatic lizards that lived during the late Cretaceous. With 'transitional' traits that place it between two well-known ...

Mosasaurs were the apex predators of the oceans during the reign of the dinosaurs, but new research reveals dinosaurs weren't safe from them in rivers either. Researchers from Sweden, the US, and the ...

Mosasaurs, giant marine reptiles that existed more than 66 million years ago, lived not only in the sea but also in rivers. This is shown by new research based on analyses of a mosasaur tooth found in ...

See more of our trusted coverage when you search. Prefer Newsweek on Google to see more of our trusted coverage when you search. A previously unknown "formidable" sea predator that lived about 90 ...

An enormous sea snake from Norse legend that was fathered by the trickster god Loki and grew big enough to circle the globe is now the namesake for a different type of “monster” — a newly discovered ...

Researchers said they had discovered a new line of mosasaur, a giant sea-dwelling creature that lived alongside the dinosaurs. Its name, Jormungandr walhallaensis, draws on Norse mythology. By Orlando ...

At the end of the Cretaceous Period, a type of giant reptile called mosasaurs occupied and dominated oceanic food webs. Mosasaurs had long bodies and were related to both snakes and monitor lizards.