Order †Pachycephalosauria Maryañska & Osmólska, 1974 see Infraorder Pachycephalosauria Maryañska & Osmólska, 1974 Family †Pachycephalosauridae Sternberg, 1945 Genus †Heishansaurus Bohlin, 1953, nom. dub. 1 †Heishansaurus pachycephalus Bohlin, 1953, nom. dub.