Class Mammalia Linnaeus, 1758 - mammals Subclass †Allotheria Marsh, 1880 Order †Multituberculata Cope, 1884 Suborder †Cimolodonta McKenna, 1975 Family †Eucosmodontidae Jepsen, 1940, incertae sedis Genus †Stygimys Sloan & Van Valen, 1965 1 †Stygimys kuszmauliᵀ Sloan & Van Valen, 1965 2 †Stygimys cupressus Fox, 1989