Full reference: R. J. Horný. 1963. On the systematic position of cyrtonelloids (Mollusca). Časopis Národni Muzea - Oddíl přírodovĕdny 132(2):90-94
Parent taxon: Tergomya according to D. E. Evans and J.C.W. Cope 2003
See also Bengtson 1992, Ebbestad and Yochelson 2000, Horný 2006, Peel 1991, Runnegar and Jell 1976, Sepkoski 2002, Starobogatov 1970 and Wahlman 1992
Sister taxa: Archinacellida, Carcassonnellidae, Halophiala, Kiringellida, Scenelloidea, Tryblidiida, Ladamarekiidae
Subtaxa: Aremellia Cyrtolitidae Cyrtonelloidea Hamusella Pollicinidae Tetamocornu Yangtzeconus
Ecology: slow-moving low-level epifaunal grazer
Distribution:
• Devonian of Czechia (7 collections), United States (17: Maine, New York)
• Silurian of Australia (1), Czechia (7), the United Kingdom (1), United States (2: Indiana)
• Dobrotivian of Czechia (1), Morocco (1)
• Liben of Czechia (1)
• Letna of Czechia (1)
• Whiterockian of United States (1: Minnesota)
• Ordovician of Australia (1), Canada (19: Ontario, Quebec, Québec), Czechia (20), Estonia (6), Morocco (5), the Russian Federation (1), Sweden (2), the United Kingdom (27), United States (109: Illinois, Iowa, Indiana, Iowa, Kentucky, Michigan, Minnesota, Missouri, New York, Ohio, Tennessee, Virginia)
• Cambrian of Antarctica (2), Australia (1), Canada (1: Alberta), China (1), the Russian Federation (2), the United Kingdom (3), United States (11: Alabama, Montana, Nevada and California, Texas, Utah, Vermont)
Total: 251 collections including 286 occurrences