Body small and slender.
Prostomium broadly rounded anteriorly, narrowing posteriorly to a narrow caruncle. Anterior pair of eyes small, posterior pair very big.
Notopodial postchaetal lobes of the first parapodia not forming a small fold around the prostomium. Notopodial postchaetal lobes triangular to leaf-like, in chaetigers 3-5 very big, posteriorly becoming shorter; in segment 7 and 6-14 following segments connected by a kind of collar across the dorsum. Neuropodial postchaetal lobes small and oval.
Anterior parapodia with winged capillary chaetae only. From neuropodium 12-16 and from notopodium 40 also 4-7 hooks. Hooks with 5-7 teeth. From segment 10-11 some spines are present on the neuropodia (P. fallax-detail).
Four pairs of gills, starting at chaetiger 2; the first and fourth pair long and feathery; the second and third pair short and smooth.
Pygidium with one long and two short cirri.
Up to 25 mm.
Yellowish to whitish.
Down to 1500 m. Lives in richly branching mucus-tubes in muddy and sandy bottoms.
North Sea to Baltic Sea, North Atlantic to Morocco, South Africa, Japan, Australia.