Cephalopoda - Dissidocerida - Geisonoceratidae
Parent taxon: Dissidocerida according to A. Pohle et al. 2022
See also Chen et al. 1981, Crick 1981, Evans 1994, Evans 1996, Evans 2005, Flower 1962, Kröger 2008, Kröger 2013, Kröger and Aubrechtova 2017, Kröger and Aubrechtová 2019, Miagkova 1967 and Teichert et al. 1964
Sister taxa: Bajkaloceratidae, Intejoceratidae, Polymeridae, Rangeroceratidae, Troedssonellidae
Subtaxa: Angeisonoceras Columenoceras Geisonoceras Geisonocerina Harrisoceras Joachimoceras Jonesoceras Nilssonoceras Ordogeisonoceras Protokionoceras Striacoceras Temperoceras Ugooloceras Virgoceras
Ecology: fast-moving nektonic carnivore
Distribution:
• Permian of Japan (1 collection)
• Carboniferous to Permian of Japan (1)
• Carboniferous of Kazakhstan (1)
• Devonian of Germany (1), Morocco (17), United States (7: New York, Ohio, Pennsylvania)
• Silurian of Canada (2: Northwest Territories, Quebec), China (7), the Czech Republic (3), Italy (13), Japan (1), Morocco (1), the Russian Federation (8), Tajikistan (2), the United Kingdom (2), United States (8: New York, Wisconsin)
• Chazyan of United States (1: New York)
• Langevoja of Sweden (1)
• Ordovician of Canada (12: Ontario, Quebec), China (1), Estonia (5), Iran (1), Ireland (4), North Korea (1), Norway (10), the Russian Federation (1), Sweden (14), the United Kingdom (3), United States (27: Illinois, Iowa, Wisconsin, Kentucky, Minnesota, New York)
Total: 156 collections including 203 occurrences