Mammalia Linnaeus 1758 [Rowe 1988], nom. cl. inval. see Class Mammalia Linnaeus, 1758 "Eutheria" Gill 1872 [O'Leary, Allard, Novacek, Meng & Gatesy 2004] see Infraclass Eutheria Gill, 1872 Genus †Protungulatum Sloan & Van Valen, 1965