Phys.org has a story about the discovery of a huge mosasaur in Morocco.  It’s been named Thalassotitan atrox, and it probably preyed on other large marine reptiles like plesiosaurs, sea turtles, and even other mosasaurs.  Mosasaurs are not dinosaurs, but actually are distant relatives of modern iguanas and monitor lizards.  The research was published in the journal Cretaceous Research.

Mosasaurs looked like a Komodo dragon with flippers instead of legs, and a shark-like tail fin. Mosasaurs became larger and more specialized in the last 25 million years of the Cretaceous, taking niches once filled by marine reptiles like plesiosaurs and ichthyosaurs. Some evolved to eat small prey like fish and squid. Others crushed ammonites and clams. The new mosasaur, named Thalassotitan atrox, evolved to prey on all the other marine reptiles.

The remains of the new species were dug up in Morocco, about an hour outside Casablanca. Here, near the end of the Cretaceous, the Atlantic flooded northern Africa. Nutrient rich waters upwelling from the depths fed blooms of plankton. Those fed small fish, feeding larger fish, which fed mosasaurs and plesiosaurs—and so on, with these marine reptiles becoming food for the giant, carnivorous Thalassotitan.