Chordata Bateson, 1885 - chordates
   Class Elasmobranchii Bonaparte, 1838 see Infraclass Elasmobranchii Bonaparte, 1838
     Subclass Selachii see Division Selachii
       Order Cestraciontes
         Suborder †Janassides
           41 Family †Janassidae Jaekel, 1898
           41.0 [Family †Petalodontidae Newberry & Worthen, 1866]
           42 Family †Psammodontidae de Koninck, 1878
           43 Family †Peripristidae Eastman, 1902
           43.0 [Family †Pristodontidae Woodward, 1889]
           44 Family †Cochliodontidae Owen, 1867
           45 Family †Tamiobatidae Hay, 1902 [monotypic] see Family Ctenacanthidae Bonaparte, 1850, "nom. praeval."