(Risso, 1818)
Description:
The body length may reach 15 mm (20 mm in the Mediterranean Sea at Naples), bright scarlet (rarely yellowish) in the typical variety, with scattered black spots dorsally and a characteristic yellowish patch between the rhinophores. The ample mantle bears innumerable close-set, short, blunt, spiculose tubercles. There may be up to ten simple pinnate yellowish gills; the lamellate rhinophores are the same colour. Finger-like oral tentacles project from the sides of the head. The propodium is bilaminate, the anterior lamina notched in the midline.
Habitat:
This conspicuous species feeds upon red sponges such as Microciona atrasanguinea , in shallow waters.
Distribution:
It has been recorded from Norway to the Mediterranean Sea (Villefranche and Naples), to 60 m (Distr. R. rubra).