Poeobiida

polychaete order

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Last updated

July 1, 2026

Quick Summary

The Poeobiida are a unique order within the class Polychaeta, which are marine worms belonging to the phylum Annelida. Unlike most polychaetes, Poeobiida have a saclike body without external segmentation. The anterior end of these worms features a circle of tentacles. Internally, they possess only two septa, which are considered their only characteristic polychaete features. Poeobiida are pelagic, meaning they live in the open sea, and the order currently contains only one genus, Poeobius.12

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Annotated classification
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 or terrestrial with setae arising directly from body wall; name of group refers to the few
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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 or terrestrial with setae arising directly from body wall; name of group refers to the few
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