Alternative spelling: Orthoceratida
Synonyms: Michelinoceratida Flower and Kummel 1950, Sinoceratida Kobayashi 1958
Parent taxon: Orthoceratoidea according to A. Pohle et al. 2022
See also Chen et al. 1981, Crick 1981, Dzik and Kiselev 1995, Evans 1994, Evans 1994, Evans 1996, Evans 2005, Evans 2011, Frey 1981, Kröger 2008, Kröger 2013, Kröger et al. 2011, Kröger and Evans 2011, Kröger and Lefebvre 2012, Sweet 1964, Teichert et al. 1964 and Tongtherm et al. 2016
Sister taxa: Actinocerida, Dissidocerida, Lituitida, Offleyoceratidae, Paraphragmitidae, Protobactritidae, Riocerida, Slemmestadoceras
Subtaxa: Acrosphaerorthoceras Allumettoceratidae Aptychopsis Arionoceratidae Arterioceras Badouceras Baltoceratidae Bogoslovskya Brachycycloceratidae Chicagooceras Choanoceratidae Cornuella Cryptocycloceras Cycloceras Cycloceratidae Dictyoceras Engorthoceratidae Eskimoceratidae Esopoceras Folioceras Garryoceras Heloceras Jangziceras Joldagiroceras Kentronites Kionoceratidae Loxoceras Mericoceras Michelinoceratidae Molossus Murchisoniceras Naivs Nebroceras Neorthoceras Orthoceratidae Orthoceratina Orthodochmiocerataceae Paradnatoceras Paramooreoceras Plicatoceras Podoliceras Proteoceratidae Pseudorthocerataceae Pseudorthoceratoidea Pythonoceras Rhabdites Rhipsites Sactorthoceratidae Sannionites Sichuanaceras Sichuanoceratidae Sphaerorthoceratidae Sphaerortoceratidae Striatoceratidae Subspyroceras Tartaroceras Tretoceras Tripteroceratidae Trispectes Uralharuspex Vericeras Zhuralevia
Ecology: nektonic carnivore