Prostomium with three lobes and two small eyespots. Gills in two groups separated by a distance of one gill and connected by a low dermal ridge; first three gills in each group in a transverse row, the fourth just behind the middle one of the three.
10-23 long, stout chaetae with sharp tips on each side in front of gills.
Fourteen thoracic segments with normal notopodia with capillary chaetae, the posterior twelve also with neuropodia with uncini. Seventeen uncinigerous abdominal segments, none with rudimentary notopodia. Uncini with two vertical rows of teeth, five teeth in each row.
Pygidium with two moderately long cirri and a number of low, conical papillae (A. goesi-detail).
Up to 50 mm long.
A thick layer of secretion encrusted with silt and often also with foraminiferans, shell fragments and sea urchin spines.
In life orange with green gills. In alcohol yellowish pink or pale yellow.
On level bottoms of fine mud or clay; 35-170 m.
Barents Sea, Siberian, Canadian and Alaskan Arctic, Bering Sea, North American Pacific, Sea of Okhotsk, Japan Sea. East Greenland, Svalbard, Iceland.