(Stimpson, 1852)
Description
External appearance
Solitary. Body globular to ovoid, up to 15 mm in diameter. Test transparent, bearing fibrils and coated with sand, shells, etc.
Characters
Both siphons 4-lobed and placed close together anteriorly. About 32 simple branchial tentacles of variable size. Branchial sac with numerous rows of straight stigmata; four branchial folds on each side; longitudinal bars present. Gut left of branchial sac; stomach distinct, with 20-25 longitudinal folds and a single small liver diverticulum. Several parallel, elongated and cylindrical gonads on each side in mantle wall (3 to 6 on the left, 4 to 8 on the right) (C. mollis morphology).
Habitat
Loosely attached to, or partly embedded in sand or mud; from shallow water to depths of at least 100 metres
Distribution
Arctic-Boreal distribution.