<==o †Biarmosuchia
   |?- †Gorgodon
   |?- †Knoxosaurus
   |?- †Steppesaurus
   |?- †Watongia
   |?- †Biarmosuchus tener Tchudinov, 1960 [Biarmosaurus, Biarmosuchus antecessor Chudinov, 1960] [Biarmosuchidae]
   |?- †Niaftasuchus zekkeli Ivakhnenko, 1990 [Niaftasuchidae Ivakhnenko, 1990]
   |?-o †Phthinosuchidae Efremov, 1954 [Phthinosuchia Romer, 1961: Phthinosauridae]
   |  |-- †Phthinosuchus discors Efremov, 1954 [=Rhopalodon pp. Seeley, 1894, Watson, 1921 and 1942, Nopsca, 1928]
   |  `-- †Phthinosaurus borissiaki Efremov, 1940'
   |?-o †Ictidorhinidae
   |  |-- †Ictidorhinus martinsi
   |  |-- †Lycaenodon
   |  |-- †Lemurosaurus
   |  `-- †Rubidgina
   |?-o †Hipposauridae
   |  |-- †Hipposaurus
   |  `?- †Pseudhipposaurus
   |?-o †Burnetiidae Broom, 1923
   |  |-- †Burnetia
   |  `-- †Proburnetia viatkensis Tatarinov, 1968a
   `--o †Eotitanosuchidae Tchudinov, 1960 [Eotitanosuchia Boonstra, 1963]
      |-- †Eotitanosuchus olsoni Tchudinov, 1960
      `-- †Ivantosaurus ensifer Tchudinov, 1983

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