Class Mammalia Linnaeus, 1758 - mammals
   Subclass Boreosphenida Luo, Cifelli & Kielan-Jaworowska, 2001 - tribotherians see Clade Boreosphenida Luo, Cifelli & Kielan-Jaworowska 2001
     Infraclass Metatheria Huxley, 1880
       Cohort †Deltatheroida Kielan-Jaworowska, 1982 see Order Deltatheroida Kielan-Jaworowska, 1982
         Family †Deltatheridiidae Gregory & Simpson, 1926
           Genus †Deltatheridiumᵀ Gregory & Simpson, 1926
             1 †Deltatheridium pretrituberculareᵀ Gregory & Simpson, 1926
             2 †Deltatheridium nessovi Averianov, 1997