(Seymouria,((Limnoscelidae,Diadectidae),(Synapsida,(Mesosauridae,(Captorhinidae,(Araeoscelidia,(Paleothyris,(Younginiformes,(Acleistorhinus,(Millerettidae,(Owenetta_kitchingorum,(Procolophon_trigoniceps,(Pareiasauria,(Odontochelys,(Proganochelys,Chelonii)))))))))))))));