(OUTGROUP,(Acanthostega_gunnari,(Ichthyostega_stensioei,((Crassigyrinus_scoticus,(Whatcheeria_deltae,(Eoherpeton_watsoni,(Proterogyrinus_scheelei,((Archeria_crassidisca,Pholiderpeton_scutigerum),(Gephyrostegus_bohemicus,(((Utegenia_shpinari,(Ariekanerpeton_sigalovi,(Discosauriscus_austriacus,D_pulcherrimus))),(Seymouria_baylorensis,S_sanjuanensis)),(Diadectes_absitus,(Tseajaia_campi,(Limnoscelis_paludis,(Eocaptorhinus_laticeps,Petrolacosaurus_kansensis))))))))))),(Greererpeton_burkemorani,(((Dendrerpeton_acadianum,(Balanerpeton_woodi,(Ecolsonia_cutlerensis,Eryops_megacephalus))),(Baphetes_kirkbyi,Megalocephalus_pachycephalus)),((Lethiscus_stocki,Sauropleura_pectinata_slash_scalaris),(Microbrachis_pelikani,Saxonerpeton_geinitzi))))))));