Body is long, cylindrical, with 19 chaetigers.
Prostomium is short, oval, slightly longer than wide, with a well developed encircling rim, laterally and posteriorly weakly incised. Nuchal slits diverging and extending only to the anterior half of the prostomium. With or without 2 groups of ocelli.
The first chaetiger is about as long as the fused prostomium-peristomium. Mid-body segments are longer, posterior segments shorter.
The first seven chaetigers with a glandular band anterioly , from segment three also posterior to the parapodia.
8th chaetiger with a large triangular lobe with glands ventrally. The following segments with glandular patches between notopodia and in the middle of the ventral side.
Notopodial chaetae are capillaries with narrow wings, some with a feathery tip.
Neuropodial chaetae are hooks starting at the first chaetiger. Anterior segments with slightly reduced hooks.
Posterior 5-6 segments without chaetae (C. lankesteri-detail).
Pygidium funnel-shaped, with 3-12 thread-like long cirri and usually 1 longer ventral cirrus.
Up to 45-70 mm for 19 chaetigers.
Tough structure, cylindrical, covered with mud, fine sand or foraminiferans.
Diameter outside 2.5 mm, inside 1.5 mm.
Chaetigers 3-7 spotted red-brown.
Muddy bottoms. Vertical distribution reaches from the upper sublittoral down to more than 4800 m deep.
Arctic, North Pacific, North Atlantic up to northern North Sea and Skagerrak, possibly eastern Baltic Sea.