Crioceratidae [SEP] parent taxon
Crioceratidae
The Crioceratidae constitute a family of loosely to closely coiled Ammonitida included in the Ancyloceratoidea that lived during the Early Cretaceous; characterized by "Crioceratites" and other genera such as "Hoplocrioceras" and "Paracrioceras".
The Crioceratidae are gyroconic, coiled in a plane, generally with space between the whorls although in some like "Balearites" the whorls are barely in contact.
Although distinct in character and not truly heteromorphic the Crioceratidae were included in the American TreatisePart L, 1957, in the Ancyloceratidae as the subfamily
Taxon in disguise
In bacteriology, a taxon in disguise is a species, genus or higher unit of biological classification whose evolutionary history reveals has evolved from another unit of similar or lower rank, making the parent unit paraphyletic. This happens when rapid evolution makes a new species appear radically different from the ancestral group, so that it is not (initially) recognised as belonging to the parent phylogenetic group, leaving the latter an evolutionary grade.
While the term is from bacteriology, parallel examples are found throughout the tree of