The Cerapods are only a group you must
have in the dinosaur "family tree". The definition of a Cerapoda is
too complicated to have only one group and because of that there are a
lot of under-groups, because of the many different dinosaurs. The
dinosaurs under this group are the duck-billed dinosaurs, the
rhino-like dinosaurs, the thickheaded dinosaurs and a dinosaur with
feetís like a bird. Therefore is the group divided into two
under-groups, the Marginocephalias and the Ornithopods.
The cerapods (or cerapoda) were a group of ornithischian (bird-hipped)
dinosaurs that included the ornithopods and the marginocephalians.