Testudines Wagler, 1830 - turtles
   Cryptodira Cope, 1868
     Testudinoidea Batsch, 1788
       Emydidae Rafinesque, 1815 - pond turtles
         Deirochelyinae Agassiz, 1857
           Trachemys Agassiz, 1857
             Trachemys grayi (Bocourt, 1868) - Gray's slider