List of currently recognized “orders” after McKenna & Bell, 1997

MAMMALIA [Mammaliaformes sensu McKenna & Bell, 1997]Sinoconodontiformes Kinman, 1994
    †Morganucodonta Kermack, Mussett & Rigney, 1973
    †Docodonta Kretzoi, 1958 sensu McKenna & Bell, 1997
    Mammalia sensu McKenna & Bell, 1997
        †Kuehneotheria
        TheriiformesAllotheriaHaramiyidaMultituberculata
            Holotheria
                TrechnotheriaAmphidontoidea Prothero, 1981
                    †Triconodonta Osborn, 1888 [paraphyletic]
                    †Spalacotheroidea Prothero, 1981
                    †Symmetrodonta
                        Mammalia sensu Luo, Cifelli & Kielan-Jaworowska, 2001 and Luo, Kielan-Jaworowska & Cifelli, 2002
                            †Yinotheria Chow & Rich, 1982
                                †Shuotherida Chow & Rich, 1982
                            Australophenida [incl. Prototheria]Ausktribosphenida Luo, Cifelli & Kielan-Jaworowska, 2001
                                Monotremata (nokkaeläimet)
                                    Platypoda (platypuses; vesinokkaeläimet)
                                    Tachyglossa (echidnas; nokkasiilit)
                            CladotheriaDryolestoideaDryolestida Prothero, 1981
                                ZatheriaAmphitheriida Prothero, 1981
                                    †Peramura McKenna, 1975
                                    BoreosphenidaAegialodontiaPappotherida Butler, 1978
                                        Theria
                                            Metatheria (marsupials and relatives; pussieläinmäiset nisäkkäät)
                                            Eutheria (Placental mammals and relatives; istukkanisäkäsmäiset nisäkkäät)

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