Giant Marine Predator Fossil Discovered in Morocco: Thalassotitan Ruled Ancient Seas

The researchers found damaged teeth, a half-meter-long plesiosaur head, as well as jaws and skulls of at least three different mosasaur species. They would have been digested in the stomach of Thalassotitan before it regurgitated their bones.

"We can’t say for certain which animal species ate all these other mosasaurs. But in the same place, we found a Thalassotitan. It’s not a coincidence," said Dr. Nick Longrich, senior lecturer at the University of Bath and lead author of the study.

The Thalassotitan fossils were discovered in Morocco, about an hour from Casablanca. It measured nearly 9 meters and had a massive skull that was 1.4 meters long. The Thalassotitan had a short, wide snout and huge teeth like those of a killer whale.

Mosasaurs were not dinosaurs, but huge marine lizards that could reach 12 meters in length. They were distant relatives of iguanas and monitors, but had flippers and no legs. They fed on fish and other marine reptiles.