Tylosaurus

Dinosaurs > Tylosaurus

Tylosaurus, meaning “swollen lizard”, was a mosasaur, a large, predatory marine lizard closely related to modern monitor lizards and to snakes. (It was not a dinosaur)

Along with plesiosaurs, sharks, fish, and other genera of mosasaurs, it was a dominant predator of the Western Interior Seaway during the Late Cretaceous. Tylosaurus proriger was among the largest of all the mosasaurs (along with Hainosaurus and Mosasaurus hoffmannii), reaching maximum lengths of 15 meters or more (49+ ft). A distinguishing characteristic of Tylosaurus is its elongated, cylindrical premaxilla (snout) from which it takes its name and which may have been used to ram and stun prey and also in intraspecific combat.

Early restorations showing Tylosaurus with a dorsal crest were based on misidentified tracheal cartilage, but when the error was discovered, depicting mosasaurs with such crests was already a trend

Stomach contents associated with specimens of Tylosaurus proriger indicate that this ferocious mosasaur had a varied diet, including fish, sharks, smaller mosasaurs, plesiosaurs, and flightless diving birds such as Hesperornis. In some paleoenvironments, Tylosaurus seems to have preferred shallow, nearshore waters (as with the Eutaw Formation and Mooreville Chalk Formation of Alabama), while favoring deeper water farther out from shore in other environments (as with the Niobrara Chalk of the western U.S.).

Tylosaurus

Clade: Reptilia
Suborder: Squamata
Family: Mosasauridae

Size: 15+ m (49+ ft) long

Weight: 12 metric tons

When: Cretaceous Period
88 to 80 million years ago

Where: North America, Western Europe

Diet: Carnivore

Though many species of Tylosaurus have been named over the years, only a few are now recognized by scientists as taxonomically valid. They are as follows: Tylosaurus proriger (Cope, 1869), from the Santonian and lower to middle Campanian of North America (Kansas, Alabama, Nebraska, etc.); Tylosaurus nepaeolicus (Cope, 1874 ), from the Santonian of North America (Kansas); Tylosaurus kansasensis Everhart, 2005, from the late Coniacian of Kansas.

A closely related genus, Hainosaurus (“Haine lizard”, named after the Haine River in Belgium) is known from the Cretaceous of North America and Europe. Both Tylosaurus and Hainosaurus are grouped together into the subfamily Tylosaurinae¬† and are referred to informally as “tylosaurines” or “tylosaurs.” Bell¬† placed the tylosaurines together with the plioplatecarpine mosasaurs (Platecarpus, Plioplatecarpus, etc.) in an informal monophyletic grouping which he called the “Russellosaurinae.”


Source: Wikipedia