Parent taxon: Heterobranchia according to A. Nützel and C. Ketwetsuriya 2016
See also Bandel 2002 and Heidelberger 2001
Sister taxa: Allogastropoda, Anomalorbis, Palaeoalvania, Stuoraxidae, Valvatoidea, Acteonoidea, Architectibranchia, Misurinella, Euthyneura, Architectonicoidea, Nerineoidea
Subtaxa: Cassianebalidae Donaldinidae Heterosubulitidae Rigauxia Streptacididae
Type: Streptacis
Ecology: epifaunal
Distribution:
• Cretaceous of France (1 collection), United States (1: Mississippi)
• Jurassic of Hungary (1), Israel (1), Tunisia (1)
• Triassic of China (6), Italy (3)
• Permian of China (9), Greece (6), Japan (1), Malaysia (1), the Russian Federation (16), Thailand (3), United States (23: Alaska, Nevada, New Mexico, Texas, Utah, Wyoming), Venezuela (1)
• Carboniferous of Australia (6), Germany (1), Japan (1), Mexico (1), the United Kingdom (26), United States (59: Arizona, Illinois, Iowa, Kansas, Kentucky, Maryland, Missouri, Nebraska, Nevada, New Mexico, Ohio, Oklahoma, Texas, Virginia, West Virginia, Wyoming)
• Devonian of Germany (2), the United Kingdom (1), United States (3: Arizona)
• Ordovician of the United Kingdom (1)
Total: 175 collections including 248 occurrences