After Rieppel, 1997 and Rieppel & Hagdorn, 1997

<==o †Eosauropterygia
   |-- †Pachypleurosauroidea Huene, 1956 [Pachypleurosauridae Nopcsa, 1928]
   `--o †Eusauropterygia Tschanz, 1989 sensu Rieppel, 1997 and Rieppel & Hagdorn, 1997
      |--o †Simosauridae
      |  |?- †Shingyisaurus
      |  `-- †Simosaurus gaillardoti Meyer, 1842
      `--o Nothosauroidea
         |?- †Sanchiaosaurus dengi
         |-- †Nothosauridae
         `--o †Pistosauroidea
            |--+?- †Corosaurus alcovensis
            |  |-- †Chinchenia sungi
            |  `-- †Kwangsisaurus orientalis
            `--o †Pistosauria Zittel, 1887 sensu Rieppel, 1998
               |-- †Augustasaurus hagdorni Sander, Rieppel & Bucher, 1997
               |--o †Cymatosaurus von Fritsch, 1894 [Cymatosauridae]
               |  |-- †C. fridericianus von Fritsch, 1894 [type]
               |  |?- †C. stensioeii (Haas, 1963) [Micronothosaurus stensioeii Haas, 1963]
               |  |?- †C. erythreus
               |  `-- †C. multidentatus
               `--+--o †Pistosaurus [Pistosauridae Zittel, 1887]
                  |  |?- †P. grandaevus
                  |  `-- †P. longaevus Meyer, 1839
                  `-- †Plesiosauria [Plesiosauroidea] (plesiosaurs; joutsenliskot)

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