Hypsilophodon_foxiStegoceras_validusLiaoceratops_yanzhiguouensisYamaceratops_gobiensisArchaeoceratops_oshimaiGraciliceratops_mongoliensisZuniceratops_christopheriTuranoceratops_tardabilisCentrosaurus_apertusTriceratops_horridusBagaceratops_rozhdestvenskyiProtoceratops_andrewsiMontanoceratops_cerorhynchusLeptoceratops_gracilisUdanoceratops_tahizhoviPrenoceratops_peiganensisPsittacosaurus_mongoliensisPsittacosaurus_sinensisChaoyangsaurus_youngiIVPP_V12722OsteologyMaximum ParsimonyBased on reanalysis of the original matrix.Sues_et_Averianov_2009a