Class Mammalia Linnaeus, 1758 - mammals
   Subclass †Allotheria Marsh, 1880
     Order †Multituberculata Cope, 1884
       Suborder †Cimolodonta McKenna, 1975
         Superfamily †Ptilodontoidea Gregory & Simpson, 1926 (1887)
           Family †Neoplagiaulacidae Ameghino, 1890
             Genus †Mesodma Jepsen, 1940
               1 †Mesodma ambiguaᵀ Jepsen, 1940
               2 †Mesodma formosa (Marsh, 1889)
               3 †Mesodma garfieldensis Archibald, 1982
               4 †Mesodma hensleighi Lillegraven, 1969
               5 †Mesodma primaeva (Lambe, 1902)
               6 †Mesodma senecta Fox, 1971
               7 †Mesodma thompsoni Clemens, 1963