Body broad, of uniform width. Prostomium as wide as long. Eyes large, rounded. Proboscis with diffusely distributed, slightly pointed, papillae, smaller and more scattered proximally. Tentacular cirri of segment 1 reaching about segment 4. Dorsal tentacular cirri of segment 2 and 3 reaching about segment 8. Ventral tentacular cirri of segment 2 as long as those of segment 1, with chaetae arising from the anterior side of the cirrophores. Dorsal cirri of median segments broadly heart-shaped, wider than long, with more or less distinct tips. Parapodial lobes rounded, with a large number of chaetae. Terminal end of chaetal shaft with the teeth slightly decreasing in size proximally. Blades short. Ventral cirri rounded, obliquely orientated upwards (N. lutea-detail).
Pygidial cirri cylindrical, 4-5 times as long as broad, with more or less pointed ends.
Living relaxed specimen 45 mm for 135 segments.
Living animals varying in colour from lemon-yellow to dark brown-red, often with darker spots on the dorsal cirri. Eyes brown. Preserved animals varying from brick-red to dark brown, dorsal cirri often darker, spots blackish. Eyes brownish black.
Mixed bottoms with mud, sand, gravel, shells and stones, between 25-300 m.
North Atlantic between Spitsbergen and Scotland, northern North Sea, Skagerrak, Kattegat and northern Öresund.