[Theria] Parker & Haswell 1897 [McKenna 1975] see Subclass Theria Parker & Haswell, 1897
   1 Marsupialia Jameson 1818 [O'Leary, Allard, Novacek, Meng & Gatesy 2004] see Cohort Marsupialia Jameson, 1818
   2 Eutheria Gill 1872 [O'Leary, Allard, Novacek, Meng & Gatesy 2004] see Infraclass Eutheria Gill, 1872