Pterygotus

General Background
Pterygotus was a Pterygotid Erypterid from the Early Silurian to the Mid Devonian all over the world except Antarctica.Pterygotus had 17(possibly 20)species with the type species being P. anglicus.They preyed on everything in the Silurian and were mid line predators in the Devonian.In the Silurian seas they had no predators but the Devonian Pterygotus were preyed on by very large fish like Dunkleosteus.Their extinction was probably due to competition from fish like Eusthenopteron.