Cestodaria

tapeworm subclass

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Last updated

June 24, 2026

Quick Summary

The Cestodaria are a subclass of tapeworms, characterized as unsegmented and possessing a single set of reproductive organs. These parasites primarily inhabit the body cavity or intestine of annelid worms and fish.1

There are approximately 105 species within this subclass, organized into three orders: Amphilinidea, Caryophyllidea, and Gyrocotylidea. These tapeworms are found as parasites in bony fish (teleosts) and, in some cases, annelids. Unlike other tapeworms, Cestodaria are not segmented and have a simpler reproductive system. Their life cycles, while complex, involve these specific hosts.12

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flatworm
Annotated classification
Subclass Cestodaria Unsegmented tapeworms containing 1 set of genitalia; parasites of the body cavity or intestine of annelid worms or fish; about 105 species. Order Amphilinidea Uterus long and N-shaped; genital pores at or near posterior extremity; intestinal parasites of teleosts (bony fish); 105 species. Order…
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Subclass Cestodaria Unsegmented tapeworms containing 1 set of genitalia; parasites of the body cavity or intestine of annelid worms or fish; about 105 species. Order Amphilinidea Uterus long and N-shaped; genital pores at or near posterior extremity; intestinal parasites of teleosts (bony fish); 105 species. Order…
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