Class Reptilia Linnaeus, 1758 - reptiles
   Subclass †Synapsida Osborn, 1903 - synapsids see Class Synapsida Osborn, 1903
     Order †Therapsida Broom, 1905 see [unranked] Therapsida Broom, 1905
       Suborder †Theriodontia Owen, 1876 [paraphyletic]
         01 Family †Phtinosuchidae
         02 Family †Brithopodidae Efremov, 1954
         03 Family †gorgonopsidae Lydekker, 1890
         04 Family †Rubidgeidae Broom, 1938
         05 Family †Ictidorhinidae Boonstra, 1952
         06 Family †Burnetiidae Broom, 1923
         07 Family †Procynosuchidae Broom, 1937
         08 Family †Thrinaxodontidae Watson & Romer, 1956
         09 Family †Cynognathidae Seeley, 1895
         10 Family †Traversodontidae Huene, 1936
         11 Family †Tritylodontidae Cope
         12 Family †Pristerognathidae Broom, 1908
         13 Family †Trochosuchidae Watson & Romer, 1956
         14 Family †Waitsiidae Haughton, 1918 see Family Whaitsiidae Haughton, 1918
         15 Family †Euchambersiidae Boonstra, 1934
         16 Family †Ictidosuchidae Broom, 1903
         17 Family †Bauriidae Broom, 1911
         18 Family †Scaloposauridae Broom, 1914
         19 Family †EriciolacertidAe Watson & Romer, 1956
         20 Family †Diarthrognathidae Crompton