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]
               Order †Thalattosauria (Merriam, 1905)
                 1 Family †Thalattosauridae Merriam, 1904
                 2 Family †Askeptosauridae Kuhn-Schnyder, 1952
                 3 Family †Claraziidae Peyer, 1936