A Kronosaurus skeleton at Harvard University has been nicknamed: "Plaster-osaurus" because they had to use so much plaster to put the skeleton back together.

Scientists still aren't sure whether Kronosaurus lay eggs on shore (she would have had to flipper her way up there!) or gave birth to live young in the sea, like ichthyosaurus did.

Kronosaurus's head was huge: up to 1/3 the size of its body.