Family Hexanchidae Gray 1851 (cow shark)
Chondrichthyes - Hexanchiformes
Parent taxon: Hexanchiformes according to D. Thies 1983
Sister taxa: Chlamydoselachidae, Eonotidanus, Pachyhexanchus, Paraheptranchias, Paranotidanus, Pseudonotidanidae, Thrinax, Welcommia, Weltonia
Subtaxa: Gladioserratus, Heptranchias, Hexanchus, Notidanodon, Notidanus, Notorhynchus, Notorynchus
Ecology: nektonic carnivore