Class [Mammalia] Linnaeus, 1758 - mammals Order Marsupialia Jameson, 1818 - marsupials see Cohort Marsupialia Jameson, 1818 Family Didelphidae Gray, 1821 - American opossums Genus Marmosa Gray, 1821 - murine opossums Marmosa andersoni Pine, 1972 - heavy-browed mouse opossum