Myzostoma

polychaete genus

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Last updated

July 1, 2026

Quick Summary

Myzostoma is a genus of aberrant annelid worms, likely related to polychaetes. These worms are parasites of echinoderms, such as starfish and sea urchins. Adult Myzostoma have a flattened, unsegmented disk shape with specialized structures on their underside for attachment and movement. They lack a vascular system and possess a unique internal structure adapted to their parasitic lifestyle. Their life cycle involves indirect development, beginning with a larval stage. The class to which Myzostoma belongs is called Myzostomaria.12

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annelid
Annotated classification
…to 1 cm; genera include Myzostoma. Order Poeobiida Body saclike without external segmentation; anterior end with circle of tentacles; 2 internal septa only polychaete characteristics; pelagic; single genus, Poeobius. Class Oligochaeta Primarily freshwater
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…to 1 cm; genera include Myzostoma. Order Poeobiida Body saclike without external segmentation; anterior end with circle of tentacles; 2 internal septa only polychaete characteristics; pelagic; single genus, Poeobius. Class Oligochaeta Primarily freshwater
Read More