Body long and cylindrical.
Neither eyes, nor gills.
Tentacles numerous (about 50). Upper lip rounded trapezoidal. Lateral lobes on segments 2 and 3, not prominent. About 10 ventral shields.
Eleven chaetigerous thoracic segments.
Notopodial chaetae from segment 4. Uncinigerous tori from segment 5, relatively short on thorax. Uncini in double rows on segments 11-18. Notopodial chaetae subdistally very finely denticulate, with long tips and narrow brims. Uncini with one big and several smaller teeth (L. venusta-detail).
Pygidium with a wavy edge.
Up to 55 mm for 67 segments.
A thin layer of secretion encrusted with mud and fine sand.
In life pink to orange with whitish ventral shields and dorsal rectangular spots. Tentacles brown or whitish. In alcohol pale yellow.
On mixed bottoms of mud or clay with sand, in moderate depths.
Brittany, Canadian and Alaskan Arctic, Siberian Arctic, Bering Sea, Sea of Okhotsk, Japan, North American Pacific, Japan Sea (L. venusta pacifica Annenkova, 1938).
East Greenland, Barents Sea, Norwegian coast, Oslofjord, Swedish west coast, Kattegat, Öresund.