After Carroll, 1988, McKenna & Bell, 1997, and Shockey & Flynn, 2007
<==o †Isotemnidae Ameghino, 1897 [paraphyletic?] |?- †Acoelohyrax |--o †Pleurostylodon Ameghino, 1897 [Pleurotemnus] | |-- †P. modicus | `-- †P. similis Ameghino, 1901 |-- †Anisotemnus distentus (Ameghino, 1901) Ameghino, 1902 [Isotemnus distentus Ameghino, 1901] L.Eoc. SA. |?- †Calodontotherium |-- †Distylophorus M.Eoc. SA. |-- †Coelostylodon L.Eoc. SA. |-- †Isotemnus [Prostylops] U.Paleoc.-L.Eoc. SA. |-- †Periphragnis harmeri [Proasmodeus armatus Ameghino, 1904] M.Eoc. SA. |-- †Pleurocoelodon U.Olig. SA. |-- †Rhyphodon M.Eoc. SA. |-- †Thomashuxleyia externa Ameghino, 1901, L.Eoc. SA. `-- †Trimerostephanos M.Eoc.-U.Olig. SA.
Reference(s):
- Carroll, R. L., 1988: Vertebrate paleontology and evolution.
–W. H. Freeman and company, New York, 1988, 698 - Carroll, R. L., 1988: Appendix. 594-648
in Carroll, R. L., 1988: Vertebrate paleontology and evolution.
–W. H. Freeman and company, New York, 1988, 698 - McKenna, M. C. & Bell, S. K., (eds.) 1997: Classification of mammals – above the species level.
–Columbia University Press, New York, 1997, xii-631 - Shockey, B. J. & Flynn, J. J., 2007: Morphological diversity in the postcranial skeleton of Casamayoran (?Middle to Late Eocene) Notoungulata and foot posture in notoungulates. –American Museum Novitates: #3601, pp. 1-26