Alternative spelling: Tetradellacea
Parent taxon: Beyrichiomorpha according to R. Schallreuter and I. Hinz-Schallreuter 2011
See also Lajblová and Kraft 2014, Liebau 2005, Salas 2011 and Schallreuter et al. 2008
Sister taxa: none
Subtaxa: Ctenoloculinidae Ctenonotellidae Sigmoopsidae Soanellidae
Ecology: epifaunal suspension feeder
Distribution:
• Silurian of United States (1: Oklahoma collection)
• Uhaku of the Russian Federation (17), Sweden (6)
• Letna of Czechia (1)
• Chazyan of Canada (2: Northwest Territories)
• Hunderum of Norway (3)
• Arenig of Bolivia (1)
• Ordovician of Argentina (1), Bolivia (2), Canada (2: Northwest Territories, Québec), Czechia (5), Estonia (2), Iran (1), Latvia (5), Lithuania (12), Morocco (2), Norway (1), the Russian Federation (27), Sweden (28), United States (7: Iowa, Minnesota)
Total: 126 collections including 183 occurrences