Parent taxon: Helcionelloida according to Y. Oh et al. 2025
See also Bouchet et al. 2017, Kouchinsky et al. 2017, Sarmiento et al. 2001, Sepkoski 2002, Thomas et al. 2020 and Wagner 2023
Sister taxa: Beshtashella, Ceratoconidae, Emargimantus, Helcionellida, Helcionelliformes, Michniakia
Subtaxa: Aldanellidae Pelagiellidae Pelagielloidea
Ecology: epifaunal grazer
Distribution:
• Ordovician of Mexico (2 collections)
• Cambrian of Antarctica (10), Australia (137), Canada (31: Newfoundland and Labrador, Nova Scotia, Quebec), China (23), Czechia (2), Estonia (1), Germany (4), Greenland (18), Guinea (1), India (1), Iran (2), Kyrgyzstan (2), Mexico (2), Mongolia (2), Morocco (2), New Zealand (1), Poland (1), the Russian Federation (76), Saint Pierre and Miquelon (1), Spain (5), Svalbard and Jan Mayen (1), Sweden (1), Türkiye (1), the United Kingdom (4), United States (33: Georgia, Idaho, Indiana, Massachusetts, Montana, Nevada, Nevada and Utah, New York, Pennsylvania, Utah, Wisconsin)
• Amgan of the Russian Federation (2)
• Solvan of Czechia (1), Kazakhstan (1), Morocco (5), the Russian Federation (3)
• Placentian of United States (6: Massachusetts)
Total: 382 collections including 462 occurrences