†unranked clade Ceratopsia Marsh 1890
Invalid subtaxa: Kulceratops Nessov 1995 [nomen dubium], Kulceratops kulensis Nessov 1995 [nomen dubium], Psittacosaurus sattayaraki Buffetaut and Ingavat 1992 [nomen dubium]
Full reference: O. C. Marsh. 1890. Additional characters of the Ceratopsidae, with notice of new Cretaceous dinosaurs. American Journal of Science 39:418-426
Parent taxon: Marginocephalia according to F.-L. Han et al. 2012
Sister taxon: Pachycephalosauria
Subtaxa: Albalophosaurus, Chaoyangosauridae, Chaoyangsauridae, Chaoyangsaurus, Eoceratopsinae, Ligabueichnium, Micropachycephalosaurus, Neoceratopsia, Psittacosauridae, Psittacosauroidea, Stenopelix, Yinlong