Description: Body long, thin and cylindrical with about 100 segments. Prostomium roundly triangular or heart-shaped with 2 small eyes and a club-shaped antenna reaching chaetiger 2 or 3 and two weakly bent nuchal slits. Notopodialpostchaetal lobes in the first chaetiger small and conical, becoming bigger until the fourth chaetiger; behind the gills thin and filamentous. Neuropodialpostchaetal lobes very small. All parapodia with capillary chaetae. Neuropodia of postbranchial segments bear also up to ten modified chaetae with a thin terminal prolongation (A. suecica-detail). Up to 30 pairs of large gills, starting at chaetiger 4. Pygidium with two long and one short cirrus.
Size: Up to 20 mm for 120 segments.
Colour: Living animal with yellowish or brownish back and dark pigmentation on prostomium and anterior segments or colourless. In alcohol brown or rust-red.
Habitat: Sublittoral to 2500 m. Muddy bottoms.
Distribution: Arctic, North Pacific, North Sea, Öresund and Baltic Sea.
Kingdom Animalia Phylum Annelida Class Polychaeta Order Cirratulida Family Paraonidae Genus Aricidea Species Aricidea suecica
