Parent taxon: Mammalia according to O. P. Hay 1930
See also Averianov and Lopatin 2011, Carroll 1988, Cope 1889, Flower 1883, Flower and Lydekker 1891, Gadow 1898, Gregory 1910, Griffiths et al. 1991, Hay 1902, Huxley 1880, McKenna 1975, Parker and Haswell 1897, Waldman and Savage 1972 and Zhou et al. 1991
Sister taxa: Acrotheria, Allotheria, Ameghinichnidae, Ameghinichnus, Anagonia, Anagonia insulata, Anisorhizus, Anisorhizus atriarius, Apotheria, Aquila ferox, Archaeorycteropus patagonicus, Arrhinolemuroidea, Atlasodon, Australosphenida, Bellua, Bondesiidae, Bunotheria, Cimolomidae, Cladotheria, Deinotheria, Diplodon ampliatus, Diplodonops, Dipodiscidae, Dipriodontidae, Ditremata, Eopentapodiscidae, Eotetrapodiscus, Eotheria, Erecta, Erythrotherium, Eutriconodonta, Eutrochodon, Florentinoameghinia, Fruitafossor, Gobiotheriodon, Helioseus, Holotheria, Holotheria, Homunculus imago, Hypotheria, Isolophodon aplanatus, Likhoeletherium, Lobodon vetus, Lophiodolodus, Lufengoconodon, Malutitetrapodiscus, Malutitetrasauropodiscus, Marsupialia, Marsupionta, Mesotheria, Microderson, Miotheria, Molapopentapodiscus, Necrolestidae, Ovovivipara, Pachydermata, Pachypithecus, Pachypithecus macrognathus, Pansirenia, Paraeopentapodiscidae, Phoca aegyptiaca, Phoca aegyptiaca antiqua, Picunia, Plagiocoelus, Pleurodon, Praephoca, Praephoca bendullensis, Prensiculantia, Promammalia, Proplanodus, Proplanodus adnepos, Prostylophorus, Prostylophorus margeriei, Protobradidae, Protobradys, Protobradys harmonicus, Ptolemaiida, Sarcobora, Schadipes, Sederipes, Simioidea, Solipedia, Sororyctidae, Stenogenium aenigmaticum, Stylodontidae, Subungulata, Sukotyro, Thereuodontidae, Theriamorpha, Tikitherium, Trichechus hydropithecus, Tricorynopus, Trilobodon, Uintatheriamorpha, Volaticotheria, Wanotherium, Yinotheria
Subtaxa: Ornithodelphia Ornithostomi