(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,Discosauriscus_pulcherrimus)),(Makowskia_laticephala,Spinarerpeton_brevicephalum)),(Seymouria_baylorensis,Seymouria_sanjuanensis))),((Diadectes_absitus,Tseajaia_campi),(Limnoscelis_paludis,(Eocaptorhinus_laticeps,Petrolacosaurus_kansensis)))))))))),(Greererpeton_burkemorani,(((Dendrerpeton_acadianum,(Balanerpeton_woodi,(Ecolsonia_cutlerensis,Eryops_megacephalus))),((Lethiscus_stocki,Sauropleura_pectinata_et_scalaris),(Microbrachis_pelikani,Saxonerpeton_geinitzi))),(Baphetes_kirkbyi,Megalocephalus_pachycephalus)))))));