Clade Cynodontia Owen 1861 [Gauthier, Kluge & Rowe 1988], nom. cl. inval. see Clade Cynodontia Owen 1861 [Rowe 2020]
   Clade Epicynodonts Hopson & Kitching 2001
     Clade Eucynodontia Kemp 1982 [Rowe 1993]
       Clade Mammaliamorpha Rowe 1988, nom. cl. inval. see Clade Mammaliamorpha Rowe 1988 [Rowe 2020]
         Family †tritheledontids Broom
           1 Genus †Pachygenelus Watson, 1913