(Psittacosaurus_mongoliensis,(Stenopelix_valdensis,Wannanosaurus_yanshiensis,Yaverlandia_bitholus,(Goyocephale_lattimorei,(Homalocephale_calathocercos,(Pachycephalosauridae_indet_Ornatotholus_browni_holotype_AMNH_5450,((Tylocephale_gilmorei,Prenocephale_prenes,Pachycephalosauridae_indet_SMP_VP_1084,Stegoceras_edmontonense_holotype_CMN_8830,Sphaerotholus_goodwini_holotype_NMMNH_P_27403,Sphaerotholus_buchholtzae_holotype_TMP_87_dot_113_dot_3,(Stygimoloch_spinifer,Pachycephalosaurus_wyomingensis)),(Stegoceras_breve_holotype_CMN_1423,(Stegoceras_sternbergi_holotype_CMN_8817,Stegoceras_lambei_holotype_CMN_8818,Stegoceras_validum_UA_2,Stegoceras_sp_Gravitholus_albertae_holotype_TMP_72_dot_27_dot_1,Stegoceras_sp_UCMP_130051))))))));