Acrioceratidae is a family of heteromorph ammonites included in the Ancyloceratoidea comprising ancyloceratid-like forms that start off with a coiled juvenile section, followed by a straight or curved shaft ending in a hook. Two described genera are included, Acrioceras and Dissimilites. The Acrioceratidae form a link, or evolutionary transition, between the loosely coiled Crioceratidae and the commonly tuberculate and heavy hooked Ancyloceratidae. Although resembling Acrioceras in general form, Toxancyloceras is included in the Ancyloceratidae where it resides as a transitional form.