ZoomDinosaurs.com Dinosaur and Paleontology Dictionary

Kronosaurus was not a dinosaur, but a plesiosaur, another type of extinct reptile. Plesiosaurs may have evolved from the Nothosaurs or the Pistosaurus, a mid-Triassic reptile.

WHEN KRONOSAURUS LIVED
Kronosaurus lived during the early Cretaceous period.

BEHAVIOR
Kronosaurus lived in the open oceans and breathed air. Some Plesiosaurs have been found with small stones in their stomachs; these may have been used to help grind up their food, or as ballast, to help them dive. They probably laid eggs in beach sand (like modern-day sea turtles).

REPRODUCTION
Kronosaurus may have laid eggs in nests that they dug into the sand, much as modern-day sea turtles do.

DIET
Kronosaurus ate ammonites and other cephalopods. Fossilized plesiosaurs and turtles have been found in the stomach cavity of Kronosaurus. Kronosaurus had strong jaws and sharp teeth. It had rounded teeth at the back of the jaws, used to crush shells. Kronosaurus was one of the top predators in the seas of the Mesozoic Era.

LOCOMOTION
Kronosaurus swam using their four paddle-like flippers in a manner similar to that of modern turtles. They might have been able to move a little bit on land, as modern seals do.

CLASSIFICATION
Kronosaurus was a plesiosaur, a marine reptile, not a dinosaur. It was a member of the following clades:

• Vertebrata
• Tetrapoda
• Diapsida - these include all the reptiles (except turtles) and birds. They are distinguished by having two holes in the rear upper part of their skulls and two holes behind the eyes.
• Sauropterygia (which includes both plesiosaurs and nothosaurs).
• (Order) Plesiosauria - the pointed-tailed flippered marine-adapted reptiles which included two types, long-necked and short-necked
• (Superfamily) Pliosauroidea - had large heads with very strong jaws, short necks, and resembled modern-day whales. They ate larger sea creatures. They included: Macroplata, Peloneustes, Liopleurodon, Kronosaurus, etc.
• Family Dolichorhynchopidae - Kronosaurus