Dunkleosteus
Genus of extinct fishes
Dunkleosteus is an extinct genus of large arthrodire ("jointed-neck") fish that existed during the Late Devonian period, about 382–358 million years ago. It was a pelagic fish inhabiting open waters, and one of the first vertebrate apex predators of any ecosystem. Fossils of Dunkleosteus have been found in the United States, Canada, Poland, Belgium, Morocco, and Russia.
From Wikipedia, under CC BY-SA. More on occurri.