Plagiorchida

flatworm order

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July 1, 2026

Quick Summary

The order Plagiorchida is a group within the class Trematoda, which are commonly known as flukes. These flatworms are typically parasitic and have complex life cycles that usually involve at least one intermediate host. A characteristic feature of the cercaria, the immature form of Plagiorchida, is the presence of a stylet, and they typically encyst in invertebrates, though occasionally in vertebrates. Most species in this order require three hosts to complete their life cycle. The family Plagiorchiidae, which belongs to this order, is a large family of digenetic trematodes.12

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flatworm
Annotated classification
Order Plagiorchida Cercaria typically armed with a stylet; encystment in invertebrates, rarely vertebrates; excretory vessels not open to the exterior. Most representatives require 3 hosts to complete one life cycle. Many hundreds of species. Order Opisthorchiida Cercaria never armed; excretory pores open on margins of tail;…
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Order Plagiorchida Cercaria typically armed with a stylet; encystment in invertebrates, rarely vertebrates; excretory vessels not open to the exterior. Most representatives require 3 hosts to complete one life cycle. Many hundreds of species. Order Opisthorchiida Cercaria never armed; excretory pores open on margins of tail;…
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