(M. Sars, 1862)
Description:
Prostomium with anterior part crescent-shaped, bearing paired lateral antennae and paired palps laterally; posterior part nearly square, with median antenna and four eyes arranged in a rectangle. Antennae and palps short, awl-shaped, subequal. Caruncle a simple sinuous crest, extending posteriorly on first three segments. Ventral mouth surrounded by anterior part of prostomium and anterior three chaetigers.
Gills with a few finger-shaped filaments start on chaetiger 2 and continue on all segments.
Dorsal and ventral cirri with basal joint. Capillary notopodial chaetae smooth or serrated, other notopodial chaetae harpoon-shaped, or forked, some are spear-shaped or arrowhead-like. Neuropodial chaetae forked, some arrowhead-like (P. borealis-chaetae).
Anus terminal, with median oval papilla.
Size:
Up to 44 mm for 23-77 segments.
Colour:
Pale yellow to pale vermilion.
Habitat:
On different kinds of substratum: shelly sand, mud, gravel, sand and pebbles, also among corals, algae, and under stones. Intertidal and shallow subtidal.
Distribution:
In North Atlantic waters and the Mediterranean, northern parts of North Sea and the English Channel.