Anomalodesmata
                  Pholadomyoida
                              Clavagelloidea
                                    Clavagellidae
                              Pandoroidea
                                    Cleidothaeridae
                                    Lyonsiidae
                                    Myochamidae
                                    Pandoridae
                              Pholadomyoidea
                                    Pholadomyidae
                              Poromyoidea
                                    Cuspidariidae
                                    Poromyidae
                                    Verticordiidae
                              Thracioidea
                                    Laternulidae
                                    Periplomatidae
                                    Thraciidae
                              Verticordioidea
                                    Euciroidae
      Cryptodonta
                  Solemyoida
                              Solemyoidea
                                    Solemyidae
      Heterodonta
                  Myoida
                              Gastrochaenoidea
                                    Gastrochaenidae
                              Hiatelloidea
                                    Hiatellidae
                              Myoidea
                                    Corbulidae
                                    Erodonidae
                                    Myidae
                              Pholadoidea
                                    Pholadidae
                                    Teredinidae
                  Veneroida
                              Arcticoidea
                                    Arcticidae
                                    Trapezidae
                              Cardioidea
                                    Cardiidae
                              Carditoidea
                                    Carditidae
                                    Condylocardiidae
                              Chamoidea
                                    Chamidae
                              Chlamydoconchoidea
                                    Chlamydoconchidae
                              Corbiculoidea
                                    Sphaeriidae
                              Crassatelloidea
                                    Astartidae
                                    Crassatellidae
                              Cyamioidea
                                    Basterotiidae
                                    Cyamiidae
                                    Neoleptonidae
                                    Sportellidae
                                    Turtoniidae
                              Cyrenoidea
                                    Cyrenidae
                                    Glauconomidae
                              Dreissenoidea
                                    Dreissenidae
                              Galeommatoidea
                                    Galeommatidae
                                    Kelliidae
                                    Lasaeidae
                                    Montacutidae
                              Glossoidea
                                    Glossidae
                                    Kelliellidae
                                    Vesicomyidae
                              Lucinoidea
                                    Cyrenoididae
                                    Fimbriidae
                                    Lucinidae
                                    Mactromyidae
                                    Thyasiridae
                                    Ungulinidae
                              Mactroidea
                                    Anatinellidae
                                    Cardiliidae
                                    Mactridae
                                    Mesodesmatidae
                              Solenoidea
                                    Cultellidae
                                    Pharidae
                                    Solenidae
                              Tellinoidea
                                    Donacidae
                                    Psammobiidae
                                    Scrobiculariidae
                                    Semelidae
                                    Solecurtidae
                                    Tellinidae
                              Veneroidea
                                    Cooperellidae
                                    Petricolidae
                                    Veneridae
      Paleoheterodonta
                  Trigonioida
                              Trigonioidea
                                    Trigoniidae
                  Unionoida
                              Etherioidea
                                    Etheriidae
                                    Hyriidae
                                    Iridinidae
                                    Mycetopodidae
                              Unionoidea
                                    Margaritiferidae
                                    Unionidae
      Paleotaxodonta
                  Nuculoida
                              Nuculanoidea
                                    Malletiidae
                                    Nuculanidae
                              Nuculoidea
                                    Nuculidae
      Pteriomorphia
                  Arcoida
                              Arcoidea
                                    Arcidae
                                    Cucullaeidae
                                    Noetiidae
                                    Parallelodontidae
                              Limopsoidea
                                    Glycymerididae
                                    Limopsidae
                                    Manzanellidae
                                    Philobryidae
                  Limoida
                              Limoidea
                                    Limidae
                  Mytiloida
                              Mytiloidea
                                    Mytilidae
                  Ostreoida
                        Ostreina
                              Dimyoidea
                                    Dimyidae
                              Ostreoidea
                                    Gryphaeidae
                                    Ostreidae
                              Plicatuloidea
                                    Plicatulidae
                        Pectinina
                              Anomioidea
                                    Anomiidae
                              Pectinoidea
                                    Pectinidae
                                    Propeamussiidae
                                    Spondylidae
                  Pterioida
                              Pinnoidea
                                    Pinnidae
                              Pterioidea
                                    Isognomonidae
                                    Malleidae
                                    Pteriidae
                                    Pulvinitidae