Class [Mammalia] Linnaeus, 1758 - mammals Order †Plesiadapiformes Simons & Tattersall, 1972 see Suborder Plesiadapiformes Simons & Tattersall, 1972 Superfamily †Plesiadapoidea Trouessart, 1897 Family †Paromomyidae Simpson, 1940 Genus †Arcius Godinot, 1984 †Arcius fuscus (Russell et al., 1967)