Eunicida

polychaete order

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June 26, 2026

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The Eunicida are an order of polychaete worms, which are marine annelids known for their segmented bodies. Polychaetes are characterized by parapodia, paired appendages on most body segments, which bear setae (bristles). Eunicida are free-moving polychaetes. Their heads may have appendages and eyes, and their proboscis includes upper and lower jaws. These worms can range from very small to as large as 3 meters (nearly 10 feet). Examples of genera within this order include Palola (known as the palolo worm), Eunice, and Lumbineris. Polychaetes, in general, play a role in marine ecosystems by processing bottom sediments.12

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Annotated classification
Order Eunicida Free-moving; head with or without appendages and eyes; proboscis with dorsal maxillae (upper jaws) of 1 to many paired pieces, a ventral pair of mandibles (lower jaws) more or less fused along the median line, and a pair of embedded maxillary carriers; parapodia single-lobed,…
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Order Eunicida Free-moving; head with or without appendages and eyes; proboscis with dorsal maxillae (upper jaws) of 1 to many paired pieces, a ventral pair of mandibles (lower jaws) more or less fused along the median line, and a pair of embedded maxillary carriers; parapodia single-lobed,…
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