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a subclass of Cestoidea, the unsegmented tapeworms of that class, which are endoparasitic in the intestines and coelom of various primitive fishes and rarely in reptiles.


A subclass of the class Cestoidea, containing tapeworms that lack a scolex and are unsegmented (monozoic), in contrast to the typical tapeworms in the subclass Cestoda; larvae of c. (called lycophora) characteristically have ten hooklets rather than six. Cestodaria are believed to be primitive tapeworms, parasitizing the intestine and celomic cavities of certain fish and a few reptiles.


A subclass of the class Cestoidea. Cestodarians are intestinal and celomic parasites of elasmobranchs and primitive telost fish. They are trematodelike but are classified with cestodes because they lack an intestine.