Ornithoprion was a small, strange-looking eugeneodont fish that lived during the Carboniferous period, around 300 million years ago, in the shallow seas that covered what is now North America. It is best known for its bizarre lower jaw, which extended forward into a long, tooth-studded spike like a saw or a beak, a feature unique among fish of its time. Ornithoprion swam with a whip-like tail and small pectoral fins, hunting small fish and soft-bodied prey in the murky coastal waters. It belonged to the eugeneodonts, a group of early cartilaginous fish related to the ancestors of sharks, which were among the top predators of the Paleozoic seas. Though it was only about half a metre long, its unusual jaw makes it one of the most distinctive and easily recognised fossils of the Carboniferous.
