About 260 million years ago, Orthacanthus was the apex predator of freshwater swamps and bayous in Europe and North America. Its body reached nearly 10 feet (3 meters) in length and owned a peculiar set of double-fanged teeth. They first appeared about 400 million years ago in the Devonian, and became extinct just before the Mesozoic, about 225 million years ago.
In The Land Before Time
A stylized Orthacantus is seen in The Land Before Time V: The Mysterious Island during the song Big Water. A second one is also seen during the same song. Due to a visual gag, it looks extremely similar to Littlefoot, except that it's a fish.