After McKenna & Bell, 1997

<==o †Agriochoeridae
   |-- †Diplobunops [Agriotherium, Chorotherium, Eomeryx, Mesagriochoerus, Protagriochoerus]
   |-- †Agriochoerus maximus
   `--o †Protoreodon
      |-- †P. walshi Theodor, 1999
      `-- †P. petersoni

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