Mosasaurus (name meaning "Meuse Lizard") is a genus of large mosasaur that originated during the Late Cretaceous period in what is now North America. The apex predator of the Cretaceous seas, this marine reptilian monster of the deep was the largest mosasaur of all time, having nothing to fear but others of its own kind when fully grown.
Thought to have been extinct for 65 million years, there are still some that remain alive on Primeval Island. In fact, they are one of the island's apex predators.
Facts[]
Era & Region[]
Mosasaurus lived during the Late Cretaceous period, around 87 – 65 million years ago. While Tyrannosaurus ruled over the land, Mosasaurus was at the top of the food chain in the Cretaceous seas.
Mosasaurus died out alongside the dinosaurs during the K/T extinction. Though not a dinosaur, Mosasaurus lived at the same time and region as them and went extinct at around the same time at the end of the Cretaceous period.
Discovery & Range[]
Since their first discovery in 1868, many Mosasaurus remains have been found in several different countries in Europe. Additionally, they have also become one of the most famous prehistoric creatures in the world.
Physical Attributes[]
The dominant marine carnivore of the Late Cretaceous seas, Mosasaurus was a giant predator that grew to reach more than 45 – 60 feet (13 – 18 m) in length and weighing 15 – 20 tons (33,000 – 44,000 lbs.), making it the largest of the mosasaur family of marine reptiles and one of the largest carnivorous animals the world had ever seen. Their serpentine shape was no accident, as they were close relatives of snakes. However, they were far more ferocious and even much larger. Smaller species lived in shallow waters close to shore. However, offshore in the deep oceans lurked true giants.
Like all mosasaurs, a long and muscular, vertically flattened tail powered Mosasaurus through the water, allowing it to ambush its prey with rapid bursts of acceleration. Paddle-like limbs helped steer the slim body covered in lizard-like scales through the water. Preserved stomach contents indicate a diet heavy on fish, but seabirds, sharks, plesiosaurs, and other mosasaurs also failed to escape Mosasaurus's lethal grip. These sea monsters were feeding on fish (Xiphactinus and sharks), sea birds (Hesperornis), and other reptiles (Archelon), plesiosaurs and other - smaller - species of mosasaurs, as well as other prey items. Its immense head size meant that it could have swallowed medium-sized animals like Squalicorax whole.
Mosasaurus was the deadliest hunter of the ancient seas, ready to seize and kill just about any creature that crossed its path with true jaws of death—lined on each side with two rows of pointy, cone-shaped teeth. Mosasaurus used its snout to locate prey, which, once inside the mosasaur's menacing jaws, was swallowed whole or torn to pieces. When the sea monster opened wide for the final gulp, two extra rows of teeth on the roof of its mouth allowed crippled captives no escape.
Behavior & Traits[]
Mosasaurus was an immensely dangerous ocean predator, by far the most dangerous that ever lived on planet Earth in the Cretaceous seas. It hunted slow-moving prey like ammonites, birds, and turtles as well as larger creatures like sharks and Elasmosaurus. Mosasaurus was not the fastest of predators. Instead of chasing its prey, Mosasaurus would stalk and then it ambushed its prey in a short burst of speed. Being caught in its jaw meant almost certain death.
And if there was anything worse than swimming with these carnivorous sea reptiles, it would be swimming with its family. Interestingly, Mosasaurus lived and travel in groups of around 20 individuals to provide protection to their offspring. They attacked and ate virtually anything that moved – sharks, turtles, giant squid, even other members of its kind, making Mosasaurus a cannibal as well as a predator.