(Müller, 1776)
Description
External appearance
Solitary. Body ovoid, usually attached by the left side and up to 20-50 mm in length. Test smooth or wrinkled, cartilaginous and bears small red papillae round the siphons. Test is semi-transparent often with red pigment visible.
Characters
Oral siphon with 6-8 lobes and placed terminal; atrial siphon 6 lobed and located relatively close (1/4 of body length) to the oral siphon. About 30-110 simple branchial tentacles, these are more numerous than the inner longitudinal vessels. Branchial sac with numerous rows of straight stigmata; no folds; no papillae at the intersections of the longitudinal and transverse vessels. Gut left of branchial sac; stomach with longitudinal folds. Ovary on the left side of the intestinal loop; testes on both sides (A. scabra morphology).
Habitat
Attached to hard substrata; from the lower shore down to depths of about 300 metres.
Distribution
From Norway to the Mediterranean.