Temporal range: Late Cretaceous
An artist's illustration of Tylosaurus proriger
Scientific classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Sauropsida
Family: Mosasauridae
Subfamily: Tylosaurinae
Genus: Tylosaurus
Marsh, 1872
Type species
Tylosaurus proriger
Cope, 1869
Referred Species
  • T. nepaeolicus (Cope, 1874)
  • T. kansasensis Everhart, 2005
  • T. pembinensis (Russell, 1988)
  • Rhamphosaurus
  • Rhinosaurus
  • Liodon dyspelor
  • Tylosaurus dyspelor

Tylosaurus was one of the deadliest hunters of the Cretaceous seas, ready to seize and kill just about any smaller creature that crossed its path with true jaws of death—lined on each side with two rows of pointy, cone-shaped teeth. Tylosaurus used its snout to locate prey, which, once inside the Mosasaurus' menacing jaws, was swallowed whole. 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. According to a new study, it hunted like an Orca ramming the prey from below before killing it.


Discovery and naming




220px-JVBA Mosasaur 6-09-2010.jpg

Tylosaurus grew more than 45 feet (14 meters) long, making it one of the largest of the marine reptiles called mosasaurs. Like all mosasaurs, a long and muscular, vertically flattened tail powered Tylosaurus 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 Tylosaurus lethal grip. Though not a dinosaur, Tylosaurus lived alongside them and went extinct at around the same time. Many Tylosaurus remains have been found in Kansas, which was once covered by a large ocean called the Western Interior Seaway.

In Popular Culture

  • A Tylosaurus appears in Jurassic Park: The Game where it consumes Dr Laura Sorkins and attempt to eat the rest of the survivors. The cloned Tylosaurus had a row spikes running down its neck to its upper back like outdated depictions of mosasaurs from the late 1800s. It also lacked a tail fluke, with another row of spikes covering the tail. The clone's skull was unlike Tylosaurus being as short as the mosasaur Platecarpus with the jaws not being completely straight. The skin color of the cloned Tylosaurus was a shade of blue with black striping and a yellowish white underbelly. It was originally the unnamed marine reptile in the game being only referred to as "Mosasaur". In Laura Sorkin's research journal, she describes the creature and labels it "Mosasaur". She also writes: "Upwards of 50 feet long, depending on genus." From this text it is clear that she doesn't know its genus, indicating that she calls the creature "Mosasaur", she refers to the family to which it belongs; which is Mosasaurs (Mosasauridae). The identity of Jurassic Park's Mosasaur was ultimately revealed to be Tylosaurus in the InGen Field Guide.
  • Tylosaurus is number 127 of the Carnivore Threes that can be created in Jurassic Park III: Park Builder. As a carnivore, it should be placed in its own enclosure, considering that if it gets placed with another animal, it will kill it. In-game it looks like a plesiosaur, probably because the game makers didn't have large enough a budget to make its own model.
  • Tylosaurus appears in the underwater park update for the game Jurassic Park: Builder.
  • 2 Tylosauruses appear in The Dino King when Speckles and One-Eye battle each other in the sea. One of the two eventually grabs One-Eye by the neck after being greviously injured by Speckles Sr. who tried to save his son. The two Tylosauruses then take him to the deeper sea.
  • Tylosaurus appears in the underwater section for the game Jurassic World: The Game as a VIP surface creature in the solid gold pack.
  • It appears in National Geographic's Sea Monsters: A Prehistoric Adventure as well as the game spinoff as the top predator.
  • It was the giant mosasaur in BBC's Chased by Sea Monsters, hunting Nigel Marven and his crew, thinking they were an Archelon.
  • It was seen as the giant mosasaur in Discovery Channel's Monsters Resurrected "T-rex of the Deep".
  • It appears in The Rite Of Spring in Fantasia where several tylosaurs appear swimming in the coastal ocean in a group, surfacing to gasp for air. Late on in the scene, one of these top predators of the sea catches a Pteranodon by the head as it skims the water's surface, fishing for squid and fish. The Tylosaurus depicted in Fantasia had spikes on its neck and back region, features that the real animal did not sport. However, this makes sense for the time as the scientists who discovered the Tylosaurus first thought that it had spines down its back, but it was discovered later on that it had a smooth back.
  • Tylosaurus was also in the Evolution's Winners the 1st episode of Dinosaur Revolution.
  • Tylosaurus appears in the popular television series SpongeBob SquarePants during episode ”Lost and Found.”
  • Tylosaurus was originally gonna appear in Dinosaur, but it never made it to the final cut. Although, there is a design of the creature for the film.



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