Vertebrata Cuvier, 1812 - vertebrates
   Gnathostomata
     Teleostomi
       Tetrapoda Hatschek & Cori 1896 [Gauthier, Kluge & Rowe 1988]
         Amniota Haeckel, 1866 [Gauthier, Kluge & Rowe 1988] - amniotes
           Class Reptilia Linnaeus, 1758 [paraphyletic] - reptiles
             Subclass Diapsida Osborn, 1903 - diapsids see Clade Diapsida Osborn 1903 [Gauthier & de Queiroz 2020]
               Infraclass Lepidosauromorpha Benton, 1983 see Subclass Lepidosauromorpha Benton, 1983
                 Superorder Lepidosauria Haeckel, 1866 see Superorder Lepidosauriformes Gauthier, Estes & de Queiroz, 1988
                   Order Sphenodontida Carroll, 1985 see Order Rhynchocephalia Günther, 1867
                     1 ?Family †Gephyrosauridae Evans, 1980
                     2 Family Sphenodontidae Cope, 1871 - tuataras
                     3 Family †Pleurosauridae Lydekker, 1888