Class Mammalia Linnaeus, 1758 - mammals †"Symmetrodontans" Simpson, 1925, incertae sedis see Infraclass Symmetrodonta Simpson, 1925 Family †Tinodontidae Marsh, 1887 [monotypic] Genus †Tinodon Marsh, 1879 †Tinodon micron Ensom & Sigogneau-Russell, 2000