Chondrichthyes - Lamniformes - Megachasmidae
Parent taxon: Lamniformes according to J. S. Nelson et al. 2016
See also Purdy et al. 2001 and Shimada et al. 2014
Sister taxa: Acutalamna, Alopiidae, Anacoracidae, Aquilolamnidae, Archaeolamnidae, Carchariidae, Carchariolamna, Cardabiodontidae, Cetorhinidae, Cretoxyrhinidae, Dallasiella, Eoptolamnidae, Haimirichiidae, Hybodus dispar, Lamna (Odontaspis) ornata, Lamnidae, Mitsukurinidae, Odontaspididae, Otodontidae, Palaeocarcharias, Paraisuridae, Pseudocarcharidae, Pseudocarchariidae, Pseudocoracidae, Pseudoisurus, Pseudoisurus tomosus, Pseudoscapanorhynchidae, Ptychodontidae, Serratolamnidae, Truyolsodontidae, Xiphodolamiidae
Subtaxa: Megachasma
Ecology: fast-moving nektonic suspension feeder-carnivore
Distribution:
• Pliocene of Belgium (1 collection), Italy (1), United States (1: North Carolina)
• Miocene to Pleistocene of Japan (1)
• Miocene of Belgium (1), Chile (1), Peru (1), United States (5: California, North Carolina, Oregon)
• Oligocene of United States (2: California, Oregon)
• Eocene of Denmark (1)
Total: 15 collections each including a single occurrence