Chordate animals having a cartilaginous or bony skull protecting the brain and major sense organs. The taxon ‘Craniata’ formerly comprised two major clades: the hagfishes, and the lampreys and jawed vertebrates. However, evidence now indicates that the hagfishes and lampreys are sister groups, and they are placed in the clade Cyclostomata. The jawed vertebrates comprise the Gnathostomata; jawless craniates are called agnathans.