(van Beneden, 1846)
Description
External appearance
Solitary. Body depressed, dome-shaped to upright and cylindrical; coloured red to brown; up to 20 mm high, not more than 15 mm in diameter. Sometimes found in aggregations of individuals.
Characters
Both siphons 4-lobed. About 30 simple branchial tentacles of variable size. Branchial sac with numerous rows of straight stigmata; 3 rudimentary folds on each side marked by groups of inner longitudinal bars. Gut on the left; stomach horizontal with longitudinal folds. One cylindrical gonad on the right side near the body wall, parallel to the endostyle. The greatest part of the gonad is ovarian; the male follicles are located alongside the ovary (D. grossularia morphology).
Habitat
Attached to hard substrata; from lower shore down to at least 600 metres;
Distribution
Arctic-Boreal distribution.