Dunkleosteus, the Largest Fish that Ever Lived

10 meter (33 foot) long Dunkleosteus terrelli, which lived about 400 million years ago, was the largest fish on Earth. This giant vertebrate weighed up to 4 tons.

It could bite with a force of 5000 newtons (1100 pounds) in 1/15 of a second. The speed with which it opened its jaws would have created a current that drew fish into its mouth

The teeth of Dunkleosteus were self-sharpening.

Dunkleosteus belonged to a class of ancient prehistoric fish called Placoderms. These fish had heavy armor, and therefore probably could not swim very fast. The Placoderms were some of the earliest fishes with jaws. They also may have been among the first vertebrates to reproduce by internal fertilization.