Class Mammalia Linnaeus, 1758 - mammals
Subclass Theria Parker & Haswell, 1897
Infraclass Metatheria Huxley, 1880
1 Order Didelphimorphia Gill, 1872 [monotypic]
2 Order Paucituberculata Ameghino, 1894 [monotypic]
3 Order Microbiotheria Ameghino, 1889 [monotypic]
4 Order Notoryctemorphia Kirsch, 1977 [monotypic]
5 Order Dasyuromorphia Gill, 1872
6 Order Peramelemorphia Ameghino, 1889
7 Order Diprotodontia Owen, 1866