Full reference: R. Zangerl. 1981. Chondrichthyes I: Paleozoic Elasmobranchii. Handbook of Paleoichthyology 3a
Parent taxon: Euselachii according to M. Ginter et al. 2010
See also Li 1988
Sister taxa: Acronemus, Artiodus, Cheirostephanus, Ctenacanthiformes, Dasyatiformes, Favusodus, Galei, Galeoidei, Hueneichthys, Hybodonta, Hybodontiformes, Musteliformes, Neoselachii, Notidaniformes, Protacrodontiformes, Scyliorhiniformes, Sphenacanthidae, Squatinoidei, Squatinorajiformes, Surcaudalus, Synechodontidae
Subtaxa: Holmesella Protacrodontidae
Ecology: nektonic carnivore
Distribution:
• Triassic of Poland (1 collection)
• Permian of United States (1: Kansas)
• Carboniferous of Belarus (1), Greenland (1), the Russian Federation (2), the United Kingdom (15), United States (8: Kansas, Missouri, Oklahoma, South Dakota)
• Devonian of Australia (3), Belarus (1), the Russian Federation (5)
Total: 38 collections including 42 occurrences