Alternative spelling: Opisthobranchiata
Parent taxon: Gastropoda according to M. Harzhauser 2007
See also Beesley 1998, Knight et al. 1960, Martin 1904, Sepkoski 2002, Squires 1989, Squires 1999 and Squires and Saul 2001
Sister taxa: Achatina, Acteonoidea, Admetidae, Alamirifica, Alectrionidae, Amalthea, Amphigastropoda, Archaeobranchia, Architectonicidae, Auroraella, Beekmanoceras, Bellerophontida, Brachycerithium, Briardia, Bucardites, Buccinites, Bulimella, Bulimulidae, Bulimus, Bullaea, Caenogastropoda, Capulus sellardsi, Catubrina, Cavolinioidea, Chartrionella, Chippewaella, Chlathrus, Chrysodomidae, Chuchleconus, Cithna, Clathromangelia, Cocculiniformia, Cyclostoma, Deroceras, Dextrobranchia, Dicathais, Dicosmus, Doliidae, Dorcasiidae, Elmira, Eogastropoda, Eunerinea, Fruiticicoiidae, Gadinidae, Galeodea schencki, Galericulus, Geinitzia, Geinitzia carinata, Globulitopa, Gordenella, Gryphellina, Gundlachia, Hecatastoma, Helicarionoidea, Helicidae, Helicites, Helictes, Helminthoglyptidae, Holyneconcha, Hyalaea, Hyalinia, Hyrcania, Isaea, Iteria, Jeffreysia, Juliidae, Liris, Lovonemetrida, Luoguella, Luoguispira, Lymnaea, Lysechinus, Lysechinus incongruens, Mahajangina, Mathildidae, Microceras, Microcochlis, Mitrularia, Monotigma, Neomphaliones, Neptuneidae, Nerinea, Neritaemorpha, Neritimorpha, Neritites, Notodelphinula, Opisthonematidae, Orthogastropoda, Patellogastropoda, Patelloidea, Pectinibranchia, Pejona, Peraubium, Permoplanorboidea, Phorus, Pitonnellus, Planorboidea, Platyostomella, Platystoma, Plectopyloidea, Pleurotomaria verticillata, Pleurotomaria verticillata, Pleurotomaria viola, Plicatusidae, Polygyridae, Pragoserpulinidae, Prasinidae, Prosobranchia, Pseudobrochidium, Pseudotylostoma, Ptenoglossa, Pteronotus, Pteropoda, Pulmonata, Pupillacea, Pyramidellidae, Pythia, Rhytidopilidae, Rotellina, Rugoplanorboidella, Scalariidae, Serpulopsis, Spiraxidae, Spirgvaleia, Streptoneura, Stuorilda, Subulinidae, Suprazonalia, Taeniodomus, Thatcheriidae, Tirolthilda, Tornatella, Tortifusus, Toxonema, Tripartella, Trochifusus, Trochiletes, Trochopsis, Trochotremaria, Trochulus, Turbo guadalupensis, Turbo texana, Urocoptidae, Valvata, Vespertilio, Vetigastropoda, Wellingtonia, Zlichovia
Subtaxa: Acanthotrophia Acochlidea Buscotypus Canepina Cephalaspida Cephalaspidea Cylindrobullinoidea Floribella Gymnosomata Heteroptygmatis Heterostrophia Lutima Mariottia Mistostigma Nicosiaella Notaspidea Paronaella Pseudofusia Reticulacella Rhodopemorpha Scorbinidola Tectibranchia Thecosomata Umbraculomorpha
Ecology: epifaunal