After Evander, 1989 and Froehlich, 2002

<==o Equidae Gray, 1821 (horses; hevoset)
   |?- †Gobihippus
   |?- †Haplohippus
   |-- †Sifrhippus sandrae (Gingerich, 1989) Froehlich, 2002
   `--+--o †Minihippus Froehlich, 2002
      |  |-- †M. index (Cope, 1873) [Hyracotherium index Cope, 1873]
      |  `-- †M. jicarillai Froehlich, 2002
      `--o †Arenahippus Froehlich, 2002 [a paraphyletic grade-taxa (metataxa) (Froehlich, 2002)]
         |-- †Arenahippus grangeri (Kitts, 1956) [Hyracotherium angustidens grangeri Kitts, 1956]
         `--+-- †Arenahippus aemulor (Gingerich, 1991) [Hyracotherium aemulor Gingerich, 1991]
            `--+-- †Arenahippus pernix (Marsh, 1876) [Eohippus pernix Marsh, 1876]
               `--+--o †Xenicohippus Bown & Kihm, 1981
                  |  |-- †X. craspedotum (Cope, 1880) [Hyracotherium craspedotum]
                  |  `--+-- †X. osborni Bown & Kihm, 1981
                  |     `-- †X. grangeri Bown & Kihm, 1981
                  `--+-- †Eohippus angustidens (Cope, 1875) Marsh, 1876 [Hyracotherium angustidens Cope, 1875; Eohippus validus Marsh, 1876]
                     `--+-- †Pliolophus vulpiceps Owen, 1858 ["Hyracotherium" vulpiceps]
                        `--o †Protorohippus Wortman, 1896 [a paraphyletic grade-taxa (metataxa) (Froehlich, 2002)]
                           |-- †Protorohippus montanum Wortman, 1896
                           `--+-- †Protorohippus venticolum (Cope, 1881) [Hyracotherium venticolum Cope, 1881; Hyracotherium vasacciense venticolum (Cope, 1881) sensu Kitts, 1956; incl.? Hyracotherium vasacciense (Cope, 1872)]
                              `--+-- †Protorohippus sp. cf. P. venticolum [Froehlich, 2002]
                                 `--+-- †Protorohippus sp. aff. P. venticolum [Froehlich, 2002]
                                    `--o †Orohippus Marsh, 1872 [a paraphyletic grade-taxa (metataxa) (Froehlich, 2002)]
                                       |?- †Orohippus proteros Korth & Evander, 1982
                                       |?- †Orohippus agilis Marsh, 1873b
                                       |?- †Orohippus progressus (Granger, 1908)
                                       |?- †Orohippus sylvaticus (Leidy, 1870d)
                                       |-- †Orohippus major Marsh, 1874a
                                       `--+-- †Orohippus pumilus (Marsh, 1871a)
                                          `--+-- †Epihippus gracilis [Duchesnehippus]
                                             `--+--o †Mesohippus Marsh, 1875 [Palaeotherium Leidy, 1850; Anchitherium Leidy, 1852; Miohippus Hay, 1902, in partim; Pediohippus Schlaikjer, 1935, in partim]
                                                |  |-- †M. celer 
                                                |  |-- †M. westoni (Cope, 1889)
                                                |  |-- †M. bairdi (Leidy, 1850) Marsh, 1875
                                                |  |-- †M. exoletus (Cope, 1874)
                                                |  `-- †M. barbouri Schlaikjer, 1931
                                                `--+--o †Miohippus Marsh, 1874 [Pediohippus]
                                                   |  |-- †M. obliquidens (Osborn, 1904) Prothero & Shubin, 1989
                                                   |  |-- †M. assiniboiensis (Lambe, 1905b) Prothero & Shubin, 1989
                                                   |  |-- †M. intermedius (Osborn & Wortman, 1895)
                                                   |  |-- †M. gidleyi (Osborn, 1904)
                                                   |  |-- †M. annectens Marsh, 1874
                                                   |  |?- †?M. equinanus Osborn, 1918
                                                   |  |-- †M. gemmarosae
                                                   |  `-- †M. validus
                                                   `--+-- †Anchitheriinae Leidy, 1869
                                                      `-- Equinae Gray, 1821 [non Leidy, 1869, Steinmann & Döderlein, 1890] (true horses; varsinaiset hevoset)

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