Parent taxon: Caenogastropoda according to B. Karapunar and A. Nützel 2022
See also Nützel and Ketwetsuriya 2016
Sister taxa: Architaenioglossa, Carinomphalus, Cassianozyga, Cataldia, Cerithimorpha, Cerithioidea, Coelodiscidae, Coelostylinidae, Cyclophoracea, Dendropupoidea, Dzikella, Epitonioidea, Idahospira, Littorinimorpha, Loxotomella, Meekospiridae, Mesogastropoda, Neontaenioglossa, Neotaenioglossa, Palaeostyloidea, Peruneloidea, Perunelomorpha, Pragoscutulidae, Prisconatica, Pseudomelanoidea, Soleniscoidea, Sorbeoconcha, Spanionematidae, Strobeidae, Trinema, Vanikoroidea, Ventrosia, Zygopleuroidea
Subtaxa: Goniasmatidae Orthonematidae
Type: Orthonema
Ecology: epifaunal
Distribution:
• Triassic of Austria (5 collections), China (40), Indonesia (1), Italy (26), Oman (1), Peru (1), Slovenia (1), Türkiye (1)
• Permian to Triassic of India (1)
• Permian of Argentina (1), Australia (1), Cambodia (4), China (18), Germany (1), Greece (5), Indonesia (1), Iran (1), Japan (3), Kyrgyzstan (1), Malaysia (1), Mexico (3), Pakistan (13), Peru (2), the Russian Federation (49), Thailand (5), United States (90: Arizona, Nevada, New Mexico, Texas, Utah, Wyoming), Venezuela (11)
• Carboniferous to Permian of China (1)
• Carboniferous of Australia (7), Canada (1: Nova Scotia), China (1), Ireland (1), Isle of Man (1), Japan (1), Libya (1), Morocco (1), the Russian Federation (18), the United Kingdom (13), United States (82: Alabama, Alaska, Arizona, Colorado, Illinois, Indiana, Iowa, Kansas, Kentucky, Missouri, Nebraska, Nevada, New Mexico, Ohio, Oklahoma, Pennsylvania, Texas, Wyoming)
• Devonian of Canada (1: Ontario), China (1), Poland (1), the United Kingdom (1), United States (4: Alaska, Iowa, Michigan, Nevada)
Total: 423 collections including 695 occurrences