Ampharete borealis can be up to 50 mm long. It can be found around Svalbard and along the northern Norwegian coast south to Møre at depths between 30 and 350 meters.
Northern Norway (Reine in Lofoten and Øksfjord in Finnmark), 90 m.
Measurements: Up to 50 mm long.
Number of thoracic chaetigers, excluding paleae: 13
Number of thoracic uncinigers: 11
Number of abdominal uncinigers: 12
Prostomium: Trilobed; one pair of eyespots.
Mouth tentacles: Papillose.
Branchiae: Four pairs of branchiae in two widely separated groups; three branchiae in each group in transverse row, with fused bases, fourth branchia free, located slightly behind the outer one of the three.
Paleae: Short with filiform tips.
Special features: First two abdominal segments with short neuropodial cirri and remaining abdominal segments with long neuropodial cirri.
Pygidium: With two long lateral cirri and several small rounded papillae.
Tube: Thin layer of organic secretion incrusted with mud.
Svalbard and northern Norwegian coast south to Møre, records further south need to be confirmed; 30–350 m (Holthe 1986a).
Ampharete borealis is most similar to Ampharete octocirrata. They can, however, be easily separated by the length and placement of the branchiae and the number of abdominal uncinigers. Ampharete borealis has shorter branchiae with one pair located slightly behind the others and 12 abdominal uncinigers. Ampharete octocirrata has longer branchiae with all the pairs in a more or less transverse row and 15 to 18 abdominal uncinigers.
Holthe T (1986a). Polychaeta Terebellomorpha. Marine Invertebrates of Scandinavia 7: 1-192.
Sars M (1856). Nye Annelider. Fauna littoralis Norvegiae (Fredrik D. Beyer. Bergen). heft 2:1-24., available online at http://biodiversitylibrary.org/page/41477013
Personal observations, Alvestad T.