Phylum [Vertebrata] (Lamarck, 1801)
Count: -
   Class Reptilia Linnaeus, 1758 - reptiles
  Count: 4o6f1g; †20o115f227g
     Subclass Diapsida Osborn, 1903 - diapsids see Clade Diapsida Osborn 1903 [Gauthier & de Queiroz 2020]
    Count: -
       Order †Ichthyosauria Blainville, 1835
      Count: -
         Family †Shastasauridae Merriam, 1902
        Count: [*] †2g
           Genus †Cymbospondylus Leidy, 1868
          Count: -
           Genus †Shonisaurus Camp, 1976
          Count: -