After McKenna & Bell, 1997 and Norris, 2000

<==o Selenodontia Scopoli, 1777 (selenodonts)
   |-- †Bunomeryx [Bunomerycidae]
   `--o Neoselenodontia
      |--o Ruminantia Scapoli, 1777 sensu Norris, 2000
      |  |?- †Protoceratidae Marsh, 1891 sensu Norris, 2000
      |  `-- Ruminantia Scapoli, 1777 (ruminants; märehtijät)
      `--o Tylopoda (Camel-like artiodactyls; kamelieläimet)
         |--o †Xiphodontidae
         |  |-- †Dichodon [Tetraselenodon]
         |  |-- †Haplomeryx
         |  |-- †Paraxiphodon
         |  `-- †Xiphodon
         `--+?-o †Protoceratoidea Marsh, 1891
            |  `-- †Protoceratidae Marsh, 1891 sensu McKenna & Bell, 1997
            `--o Cameloidea Gray, 1821 (kamelinsukuiset kamelieläimet)
               |?- †Oromerycidae
               `-- Camelidae Gray, 1821 (camels; kamelit)

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