Phylum [Vertebrata] (Lamarck, 1801)
   Class Reptilia Linnaeus, 1758 - reptiles
     Subclass Diapsida Osborn, 1903 - diapsids see Clade Diapsida Osborn 1903 [Gauthier & de Queiroz 2020]
       Order †Araeoscelida see Order Araeoscelidia Williston, 1913
         1 Family †Petrolacosauridae Peabody, 1952
         2 Family †Araeoscelididae