Mammalia Linnaeus 1758 [Rowe 1988], nom. cl. inval. see Clade Mammalia Linnaeus 1758 [Rowe 2020]
Count: [*†*] 6o;1f;14g; †7o;26f;156g;4s
   Metatheria Huxley 1880 [O'Leary, Allard, Novacek, Meng & Gatesy 2004] see Infraclass Metatheria Huxley, 1880
  Count: [*†*] 6o;1f;14g; †6o;26f;143g;4s
     Marsupialiformes Vullo, Gheerbrant, de Muizon & Néraudeau, 2009
    Count: [*†*] 6o;1f;14g; †5o;25f;134g;4s
       [Order] †Peradectia Marshall, Case & Woodburne, 1990
      Count: [†*] †4f;18g [29 Mar 2022]
         Superfamily †Peradectoidea Marshall et al., 1990 see Order Peradectia Marshall, Case & Woodburne, 1990
        Count: [†*] †3f;10g [29 Mar 2022]
           1.1 Family †Mayulestidae de Muizon, 1994 [monotypic]
          Count: [†*] †1g [29 Mar 2022]
           1.2 Family †Pucadelphyidae de Muizon, 1998
          Count: [†*] †2g [29 Mar 2022]
           2 Family †Peradectidae Crochet, 1979
          Count: [†*] †7g [29 Mar 2022]