(Linnaeus, 1767)
Description:
Up to 25 chaetigers; 3 thoracic chaetigers.
About 4 pairs of radioli with thin, tapering tip, which is 2-3 as long as the distal pinnule.
Non-brooding operculum with a flat or concave distal plate and a peripheral subtriangular talon, proximal margin of which remains attached to outer edge of the flat-topped brood chamber which has a helmet-shaped calcification (J. granulata-operculum).
The first notopodia with capillary chaetae and special collar chaetae, which are finely toothed and without cross-striations. Apomatus-chaetae on third thoracic notopodium. Thoracic uncini with two longitudinal rows of small teeth.
Abdominal chaetae are strongly geniculate with large teeth along the upper margin of the distal part.
Largest abdominal tori three-quarters of the way along the abdomen.
Size:
Up to 25 chaetigers.
Tube:
Calcareous tube coiled clockwise, 2-3 mm in diameter. Usually without longitudinal ridges.
Colour:
Abdomen transparent, thorax with yellowish or orange coloured glimmer.
Habitat:
Under rocks and shells; sublittoral, in shallow water only in sheltered conditions.
Distribution:
Arctic, Northeast Atlantic, English Channel, North Sea, Skagerrak, Kattegat, the Belts and Öresund and western Baltic Sea up to Warnemünde.