Strigeidida

flatworm order

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July 14, 2026

Quick Summary

The term "Strigeidida" refers to an order of digenetic trematodes, which are parasitic flatworms. These organisms are characterized by a fork-tailed cercaria (an immature form) and the presence of penetration glands. They typically have one to two pairs of protonephridia, which are excretory organs.1

The family Strigeidae, within this order, includes parasites found in mammals and birds. These trematodes have a flattened or cuplike anterior end and a cylindrical posterior end. The adjective "strigeid" and the noun "strigeid" are related terms used to describe or refer to members of the Strigeidae family.234

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flatworm
Annotated classification
Order Strigeidida Cercaria (immature form) fork-tailed; penetration glands present; 1–2 pairs of protonephridia; about 1,350 species. Order Echinostomida Cercaria with simple tail and many cyst-producing glands; life cycle with 3 hosts; about 1,360 species. Order Plagiorchida
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Order Strigeidida Cercaria (immature form) fork-tailed; penetration glands present; 1–2 pairs of protonephridia; about 1,350 species. Order Echinostomida Cercaria with simple tail and many cyst-producing glands; life cycle with 3 hosts; about 1,360 species. Order Plagiorchida
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