<==o PERISSODACTYLA Owen, 1848 [Mesaxonia] (kavioeläimet)
   |-- †BRONTOTHEROIDEA [Titanotheriomorpha Hooker, 1989]
   |-- HIPPOMORPHA (hevosmaiset kavioeläimet)
   `--o MEROPOMORPHA [Tapiromorpha] (tapiirimaiset kavioeläimet)
      |--o †ISECTOLOPHOMORPHA Peterson, 1915 sensu Prothero & Schoch, 1989
      |  `-- †Isectolophidae Peterson, 1915 [1919 (Schoch, 1989)] [paraphyletic assemblage of basal meropomorphs]
      `--o RHINOTAPIROMORPHA Prothero & Schoch, 1989 (sarvikuono-tapiirimaiset kavioeläimet)
         |-- †Kalakotia simplicidentata Ranga Rao, 1972 [Aulaxolophus quadrangularis, Chasmotherium mckennai, Schlosseria radinskyi]
         |--o †ANKYLOPODA Cope, 1889 sensu Prothero & Schoch, 1989
         |  |-- †Lophiodontidae Gill, 1872 [Lophiodontoidea Gill, 1872]
         |  `-- †CHALICOTHEROIDEA
         `--o CERATOMORPHA (sarvikuonomaiset kavioeläimet)
            |-- †Breviodon Radinsky, 1965
            |-- †Parabreviodon Reshetov, 1975
            `--+-- †Deperetellidae Radinsky, 1965 sensu Hooker, 1989 [Deperetellidea Radinsky, 1965 sensu Prothero & Schoch, 1989]
               |-- †Lophialetidae Matthew & Granger, 1925b sensu Radinsky, 1965b [Lophialetidea Matthew & Granger, 1925b sensu Prothero & Schoch, 1989]
               `--o TAPIRIDEA sensu Prothero & Schoch, 1989
                  |-- RHINOCEROTOIDEA (sarvikuononsukuiset kavioeläimet)
                  `--+-- †Heptodon calciculus Cope, 1882 [Lophiodon ventorum Cope, 1880]
                     `-- TAPIROIDEA Burnett, 1830 sensu Prothero & Schoch, 1989 (tapiirinsukuiset kavioeläimet)

Reference(s):

Albright III, L. B., 1998: New genus of tapir (Mammalia: Tapiridae) from the Arikareean (Earliest Miocene) of the Texas Coastal Plain.
–Journal of Vertebrate Paleontology: Vol. 18, #1, pp. 200-217

Froelich, D. J., 1999: Phylogenetic systematics of basal perissodactyls.
–Journal of Vertebrate Paleontology: Vol. 19, #1, pp. 140 - 159

Hooker, J. J., 1989: Character polarities in early perissodactyls and their significance for Hyracotherium and infraordinal relationships. 79-101.
in Prothero, D. R. & Schoch, R. M., (eds.) 1989: The Evolution of Perissodactyls.
–Oxford University Press, New York, New York & Oxford, England, 1989, ix-537

McKenna, M. C. & Bell, S. K., (eds.) 1997: Classification of mammals – above the species level.
–Columbia University Press, New York, 1997, xii-631

Prothero, D. R. & Schoch, R. M., 1989: Classification of the Perissodactyla. 530-537.
in Prothero, D. R. & Schoch, R. M., (eds.) 1989: The evolution of perissodactyls.
–Oxford University Press, New York, 1989, ix-537

Schoch, R. M., 1989: A brief historical review of Perissodactyl classification. 13-23.
in Prothero, D. R. & Schoch, R. M., (eds.) 1989: The Evolution of Perissodactyls.
--Oxford University Press, New York, 1989, ix-537

Schoch, R. M., 1989: A review of the tapiroids. 298-320
in Prothero, D. R. & Schoch, R. M., (eds.) 1989: The Evolution of Perissodactyls.
–Oxford University Press, New York, New York & Oxford, England, 1989, ix-537

Thewissen, J. G. M., Williams, E. M. & Hussain, S. T., 2001: Eocene mammals faunas from Northern Indo-Pakistan.
–Journal of Vertebrate Paleontology: Vol. 21, #2, pp. 347-366