(Sars, 1872)
Description:
Body long and slender.
Prostomium oval, with a pair of ovoid frontal palps and a pair of cushion-like ventral palps. Five antennae with about six basal annulations. Sometimes two small eyes present. Peristomium with a pair of slender, cylindrical peristomial cirri near the anterior margin. First three chaetigers with somewhat enlarged and forwardly directed parapodia, with short and awl-shaped ventral cirri. Following ventral cirri globular. Dorsal cirri cylindrical, somewhat longer than the parapodial lobes (P. quadricuspis-parapodium).
Gills start at chaetiger 5-9, absent from a long posterior region, with four or five filaments where best developed.
First five parapodia with three kinds of chaetae: capillary, pseudoarticulate and hooded hooks with bifid or trifid tips. Other parapodia with: capillary chaetae, comb-chaetae and one to three stout bidentate hooks starting at chaetigers 10-17 (P. quadricuspis-chaetae).
Two long and two short pygidial cirri.
Mandibles X-shaped. Maxillae I: a hooked forceps; maxillae II: with 7-8 teeth each; maxillae III: with 6-8 teeth each; maxillae IV: with 4-6 and 7-8 teeth; maxillae V: unidentate. Maxillary carriers triangular (P. quadricuspis-maxillae).
Size:
Up to 60 mm for up to 160 segments.
Tube:
Cylindrical, membranous lining encrusted with mud or fine shell debris.
Colour:
Living animal with one wide reddish brown band per segment.
Habitat:
Sand and mud or mixtures of both with gravel and pebbles from 40 to 2000 m.
Distribution:
North Pacific, north to middle Atlantic, northern North Sea, Skagerrak and Kattegat.