Parent taxon: Orthocerida according to D. H. Evans 2000
Sister taxa: Acrosphaerorthoceras, Aptychopsis, Arionoceratidae, Arterioceras, Badouceras, Baltoceratidae, Bogoslovskya, Brachycycloceratidae, Chicagooceras, Cornuella, Cryptocycloceras, Cycloceras, Dictyoceras, Esopoceras, Folioceras, Garryoceras, Heloceras, Jangziceras, Joldagiroceras, Kentronites, Kionoceratidae, Loxoceras, Mericoceras, Molossus, Murchisoniceras, Naivs, Nebroceras, Neorthoceras, Orthoceratidae, Orthoceratina, Orthodochmiocerataceae, Paradnatoceras, Paramooreoceras, Plicatoceras, Podoliceras, Proteoceratidae, Pseudorthocerataceae, Pythonoceras, Rhabdites, Rhipsites, Sactorthoceratidae, Sannionites, Sichuanaceras, Sichuanoceratidae, Sphaerorthoceratidae, Sphaerortoceratidae, Subspyroceras, Tartaroceras, Tretoceras, Tripteroceratidae, Trispectes, Uralharuspex, Vericeras, Zhuralevia, Allumettoceratidae, Michelinoceratidae, Cycloceratidae, Engorthoceratidae, Choanoceratidae, Striatoceratidae, Eskimoceratidae
Subtaxa: Sactoceratidae
Ecology: nektonic carnivore
Distribution:
• Silurian of Canada (3: Manitoba, Ontario collections), the Czech Republic (2), Italy (1), the Russian Federation (3)
• Arenig of China (2)
• Ordovician of Canada (4: Ontario), China (4), Norway (3), Saudi Arabia (1)
Total: 23 collections including 24 occurrences