(Savigny, 1816)
Description
External appearance
Solitary. Body ovoid, globular or conical, up to 70 mm in length.Test leathery, wrinkled and mammilalated, brownish in colour.
Characters
Both siphons 4-lobed. About 56 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 horizontal with longitudinal folds and a single small liver diverticulum. Numerous drop-shaped polycarps scattered over each side of mantle wall (P. pomaria morphology).
Habitat
Attached to hard substrata; from shallow water down to about 450 meters;
Distribution
From Spitsbergen and Norway down to the Mediterranean.