hybodonts

Hybodonts were an extinct order of sharks that lived from the Devonian period to the end of the Cretaceous period. They were a diverse group, ranging in size from small, bottom-dwelling species to large, open-water predators. Hybodonts are characterized by their distinctive teeth, which were broad and blunt, suitable for crushing prey like shellfish and crustaceans. Their fin anatomy also differed from modern sharks, with distinct dorsal fin spines and a less heterocercal tail.

Fossil evidence indicates that hybodonts were widespread across the globe, inhabiting both freshwater and marine environments. They occupied a variety of ecological niches, coexisting with other shark groups and predatory fish. The decline and eventual extinction of hybodonts coincided with the end-Cretaceous mass extinction event, which significantly altered marine ecosystems. While they are no longer present today, their fossils provide valuable insights into the evolutionary history of sharks and the ancient marine food webs they inhabited. Their presence through the Mesozoic Era suggests they were successful and adaptable predators for a very long time.