Synonym: Dibranchiata Owen 1836
Parent taxon: Cephalopoda according to R. Hoffmann et al. 2022
See also Boyle and Rodhouse 2005, Fuchs et al. 2013, Fuchs and Schweigert 2018, Green 1977, Jeletzky 1966, Kretzoi 1942, Martill and Barker 2006, Nishiguchi and Mapes 2008, Pohle et al. 2022, Squires 1984 and Wells and Houston 2001
Sister taxa: Actinoceratoidea, Akidocheilus, Ammonoidea, Anomalosaepiidae, Avramidiscus, Barrandeocerida, Belosaepia, Burronoceras, Dartoceras, Davidiceras, Desmoceras, Didymoceras, Ectocochlia, Ellesmerocerida, Endoceratoidea, Endocycloceratidae, Erlangericheilus, Gonatocheilus, Hadrocheilus, Irianoceras, Lamellaptychus, Leptocheilus, Mesoteuthoidea, Multiceratoidea, Nautilia, Nautiloidea, Nautilus (Solenochilus), Ohioceratidae, Orthoceratoidea, Orthoceratoidea, Palaeoteuthis, Plectronoceratia, Plectronocerida, Rhyncholithes, Rhynchoteuthis, Robsonoceratidae, Scaptorrhynchus, Sichunoceras, Stemtonoceratidae, Tarphyceratia, Teratoceroides, Tetrabranchiata, Tillicheilus, Werthenoceras, Yanhecerida
Subtaxa: Aulacocerida Bactritoida Belemnoida Belemnoidea Belemnomorpha Decacera Decembrachiata Glochinomorpha Jeletzkya Loligosepiida Neocoleoidea Onychoteuthis Palaeoteuthomorpha Phragmoteuthidida Pohlsepia Teuthidea Ticinoteuthis
Ecology: fast-moving nektonic carnivore