(Théel, 1879)
Description:
Body long, cylindrical, anteriorly slightly flattened.
Prostomium rounded, with two dorsolateral nuchal organs and two tentacles (easily lost). Eyes absent.
1st segment without notopodia (sometimes also segments 7-10). The next 10 chaetigers with a cylindrical notopodium supported by an internal acicula; no chaetea. Chaetiger 1 to 7 with cirriform or lanceolate interramal cirrus. Neuropodia of anterior 2 or 3 segments with a triangular subpodial papilla, on chaetiger 4 with a subpodial lobe with 4-6 big papillae, on chaetiger 5 and 6 big, triangular lobes with many small papillae, chaetiger 7 with a big lobe with 6-14 big and conical papillae and chaetigers 8-11 each with a big, finely papillated lobe. Posterior neuropodia conical with several aciculae. Chaetae all variously modified capillaries (A. tullbergi-detail).
Pygidium with two long and one short cirri.
Size:
Unknown. Fragments of over 35 segments 12 mm long.
Colour:
Whitish to yellowish.
Habitat:
Coarse sand, mud and muddy sand, also on seaweeds and Zostera. Upper sublittoral to 360 m.
Distribution:
Arctic, North Pacific, North Atlantic to Mediterranean, northern North Sea to Öresund.