Class Mammalia Linnaeus, 1758 - mammals Subclass Theria Parker & Haswell, 1897 Order Didelphimorphia Gill, 1872 Family Didelphidae Gray, 1821 - American opossums 1 Subfamily Caluromyinae Kirsch & Reig, 1977 2 Subfamily Didelphinae Gray, 1821