Ceratopsia Leptoceratops Marginocephalia Chaoyangsaurus Yinlong Zuniceratops Styracosaurus Wannanosaurus Homalocephale Beg tse Pentaceratops Stygimoloch Pachycephalosauria Ceratopsidae Centrosaurinae Centrosaurus Triceratops Pachycephalosaurus Psittacosaurus