Class Mammalia Linnaeus, 1758 - mammals Subclass Theria Parker & Haswell, 1897 Order Didelphimorphia Gill, 1872 Family Didelphidae Gray, 1821 - American opossums Subfamily Didelphinae Gray, 1821 Genus Lutreolina Thomas, 1910 - thick-tailed opossum 1 Lutreolina crassicaudata (Desmarest, 1804) - lutrine opossum