Micropachycephalosaurus
The lack of the skull roof means the fossil cannot be placed at family level. It might or might not be a pachycephalosaur. Butler and Zhao therefore classified it as an indeterminate member of the Cerapoda. In 2011, cladistic analysis showed that Micropachycephalosaurus is a basal member of the Ceratopsia. In this context, basal does not mean 'ancestral'; the fossil is far too late for that. It means simply 'unspecialized', or lacking derived traits.