Body club-shaped with a slender posterior part, covered with epidermal papillae; often encrusted with sand-grains or mud.
Prostomium and peristomium retractile, with ten finger-like gills, without eyes. 2 long thick palps with a median groove.
Cephalic cage formed by long, annulated, iridescent, capillary chaetae of the first two chaetigers. The anterior border of the first chaetiger is divided into 3 lappets with long, thread-like papillae.
Notopodial chaetae all capillary, short, thin and annulated. Neuropodial chaetae capillary and 2-5 brown spines, starting at chaetiger 3-9 (P. flabellata-detail).
Up to 25 mm for 30 segments.
Grey, posteriorly brownish.
Mud and sandy mud, upper sublittoral to 550 m.
Eastern North Atlantic, North Sea to Kattegat.