Genus: Micropachycephalosaurus DONG, 1978
Etymology: Greek, mikros, “small” + Pachycehalosaurus”: “small pachycephalosaur”.

Species: hongtuyanensis DONG, 1978
Etymology: In reference to Hongtuyan, Shangtung Province, China.

Holotype: IVPP V5542

Locality: Hongtuyan, South of Laiyang City, Shandong (Shantung) Province, China.

Horizon: Wangshi Formation.


Age: Campanian Stage, Senonian Subeopch, Gulf Epoch, Late Cretaceous.

Material: Left quadrate, partial tooth row with 7 teeth preserved in original positions, partial tooth row with 5 alveoli (no teeth preserved), 1 loose tooth, partial basioccipital, centra of 3 posterior dorsal and 2 sacral vertebrae, associated with impressions of the neural spines of the posteriormost dorsal and 4 sacrals, 4 partial caudal vertebrae presevere in near articulation with associated chevrons, isolated centa of 7 caudal vertebrae, 1 with a partial neural arch, isolated partial caudal neural arch, partial left ilium, left femur, and the proximal portion of the left tibia.

Note: DONG, 1978 breifly described, but did not figure, a parietal and squamosal; however, no bone of the skull roof can be identified in the holotype specimen (BUTLER & ZHAO, 2008)