Parapodium

Parapodia (Gr. para, beyond or beside + podia, feet), singular parapodium, are paired un-jointed lateral outgrowths from the body of two different invertebrate groups, which are primarily marine in habitat.

These unjointed structures are characteristic of polychaete worms, Polychaeta. Parapodia are also characteristic of several clades of sea snails and sea slugs, opisthobranch gastropod molluscs:

In polychaete worms

Parapodia in polychaetes are either uniramous or biramous. In the latter case, the dorsal lobes or branches are called notopodia and the ventral branches neuropodia.

Both neuropodia and notopodia can bear cirri (called respectively neurocirri and notocirri) and setae (called respectively neurosetae and notosetae). The cirri between the two branches are called interramal cirri.

In opisthobranch gastropod mollusks

The fleshy protrusions on the sides of some snails are also called parapodia (they are particularly well-developed in sea butterflies). Some sea hares also use their parapodia to swim.

Parapodia are found in: Clade Cephalaspidea
Clade Thecosomata
Clade Gymnosomata
Clade Aplysiomorpha

Translation

The word "Parapodium" occurs as such in the following languages: English, German, Polish.

Translation(s) in other languages: Portuguese: Parápode, Serbian: Параподија.