After Shoshoni & Tassy, (eds.), 1996

<==o †Mammutidea Hay, 1922 non Cabrera, 1929 [Mammutoidea Hay, 1922] (mastodonts; mastodontit)
   |-- †Eozygodon morotoensis
   `--+--o †Zygolophodon Vacek, 1877 [Turicius]
      |  |-- †Z. aegyptensis Sanders & Miller, 2002
      |  |-- †Z. tapiroides (Cuvier)
      |  |-- †Z. gromovae
      |  |-- †Z. proavus
      |  `--o †Z. turicensis -group
      |     |-- †Z. turicensis
      |     |-- †Z. atavus [subspecies to Z. turicensis??]
      |     |-- †Z. metachijiensis [subspecies to Z. turicensis??]
      |     `-- †Z. gobiensis [subspecies to Z. turicensis??]
      `--+?- †“Zygolophodon” merriami
         `--o †Mammut [Zygolophodon]
            |-- †M. matthewi
            |-- †M. borsoni (Hays, 1834) [Zygolophodon borsoni (Hays, 1834)]
            `-- †M. americana (amerikanmastodontti)

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