After McKenna & Bell, 1997

Microbiotherium Ameghino, 1887
      ?including:Stylognathus Ameghino, 1891
        †Eodidelphys Ameghino, 1891
        †Prodidelphys Ameghino, 1891
        †Hadrorhynchus Ameghino, 1891
        †Proteodidelphys Ameghino, 1898
        †Oligobiotherium Ameghino, 1902
        †Clenia Ameghino, 1904
        †ClenialitesAmeghino, 1906
        †Microbiotheridion Ringuelet, 1953

        †Microbiotherium acclinumMicrobiotherium forticulumMicrobiotherium gallegosenseMicrobiotherium patagonicumMicrobiotherium tehuelchumMicrobiotherium tortor

Reference(s):