Eugeneodontidae

The Eugeneodontidae is an extinct family of cartilaginous fish known from the Carboniferous, Permian, and potentially Devonian periods of the United States, Iran, and possibly Belgium, Poland and Russia. The eugeneodontids are known primarily from fossilized teeth, as well as the remains of the jaws, gills and in some species nearly complete skeletons with coatings of dermal denticles. The genera Bobbodus, Gilliodus and the type genus Eugeneodus are included within the family. Eugeneodontidae is considered the sister group to the family Caseodontidae, and the two are included together within the suborder Caseodontoidea and the order Eugeneodontiformes. The type genus, and by extension the family and the order Eugeneodontiformes are named in honor of Paleontologist Eugene S. Richardson Jr.

Members of the family are united by the structure of their teeth, which consist of both rows of flat, tightly packed tooth-plates which form what is known as a "pavement dentition" and a single row of teeth along the midline of the lower jaw known as a tooth whorl. While other members of Eugeneodontida possess a similar arrangement, the Eugeneodontidae is unique in that their pavement teeth have bladed cutting edges. Members of this family have been proposed to have been evolutionarily primitive members of Eugeneodontiformes, due to features of their upper jaws and caudal fins. Members of the family are thought to have been durophagous carnivores which inhabited marine environments. The family became extinct during the Late Permian.