Order Testudines Wagler, 1830 - turtles
   Suborder Cryptodira Cope, 1868
     Superfamily Testudinoidea Batsch, 1788
       Family Testudinidae Batsch, 1788 - tortoises
         Genus Pyxis Bell, 1827
           Pyxis arachnoides Bell, 1827 - spider tortoise
             Pyxis arachnoides oblonga Gray, 1869 - southern spider tortoise