After McKenna & Bell, 1997 and Dubrovo & Sanders, 2000

<==o †Squalodontoidea Brandt, 1872
   |--o †Squalodontidae Brandt, 1872
   |  |-- †Parasqualodon
   |  |-- †Metasqualodon
   |  |-- †Eosqualodon
   |  |-- †Prosqualodon
   |  |-- †Agriocetus
   |  |-- †Saurocetus
   |  |-- †Colophonodon
   |  |-- †Sulakocetus
   |  |-- †Squalodon [Phocodon, Rhytisodon]
   |  |-- †Kelloggia
   |  |-- †Microcetus sharkovi
   |  |-- †Neosqualodon
   |  |-- †Phoberodon
   |  |-- †Sachalinocetus
   |  `--o Patriocetinae
   |     `--o †Patriocetus (van Beneden, 1865)
   |        |-- †P. sp. indet.
   |        |-- †P. ehrlichi (van Beneden, 1865)
   |        `-- †P. kazakhstanicus Dubrovo & Sanders, 2000
   |?-o †Waipatiidae
   |  `-- †Waipatia maerewhenua
   `--o †Rhabdosteidae [Eurhinodelphidae]
      |-- †Eurhinodelphis
      |-- †Macrodelphinus
      |-- †Ziphiodelphis abeli
      |-- †Rhabdosteus
      |-- †Argyrocetus
      `-- †Phocaenopsis

Reference(s):