Order Testudines Wagler, 1830 - turtles
   Suborder Cryptodira Cope, 1868
     Superfamily Kinosternoidea Agassiz, 1857
       Family Kinosternidae Agassiz, 1857 - mud and musk turtles
         Subfamily Staurotypinae Gray, 1869
           Genus Staurotypus Wagler, 1830
             1 Staurotypus salvinii Gray, 1864 - Pacific Coast giant musk turtle
             2 Staurotypus triporcatus (Wiegmann, 1828) - northern giant musk turtle