Class [Mammalia] Linnaeus, 1758 - mammals Order Marsupialia Jameson, 1818 - marsupials see Cohort Marsupialia Jameson, 1818 Family Didelphidae Gray, 1821 - American opossums Genus Gracilinanus Gardner & Creighton, 1989 Gracilinanus aceramarcae (Tate, 1931) - Aceramarca gracile opossum