parapodium

anatomy

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June 23, 2026

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A parapodium is a fleshy, lateral appendage found on most segments of a polychaete worm. These structures are crucial for locomotion, aiding in movement by providing points of contact and propulsion. In some species, parapodia contain bundles of setae, which are bristle-like structures that assist in gripping surfaces.123

In certain marine gastropods, known as pteropods, the term parapodia refers to a pair of wing-like flaps that have evolved from the foot. These modified structures are used for swimming, allowing the pteropods to navigate near the sea surface. The adjective form is parapodial, meaning "of or relating to a parapodium".45

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gastropod
The foot
…projections of the foot called parapodia; they are used in swimming or else are reflexed over the shell surface. An unusual feature found in several kinds of land slugs, some nudibranchs, and the neogastropod marine family Harpidae is the ability to self-amputate the posterior portion of the foot, which remains…
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…projections of the foot called parapodia; they are used in swimming or else are reflexed over the shell surface. An unusual feature found in several kinds of land slugs, some nudibranchs, and the neogastropod marine family Harpidae is the ability to self-amputate the posterior portion of the foot, which remains…
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annelid
Polychaetes
…segment (peristome) usually has paired parapodia; i.e., fleshy, lateral outgrowths used in feeding, locomotion, or breathing. The parapodia, generally prominent in free-moving polychaetes, bear bundles of setae, which can be extended, and aciculae (needlelike structures), which are used for support.
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…segment (peristome) usually has paired parapodia; i.e., fleshy, lateral outgrowths used in feeding, locomotion, or breathing. The parapodia, generally prominent in free-moving polychaetes, bear bundles of setae, which can be extended, and aciculae (needlelike structures), which are used for support.
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