Acanthodoris pilosa (Abildgaard in Müller, 1789)

29 April, 2011.
Eight Mile Reef, Loch Etive on the west coast. 
22 mm animal at 12 m on bryozoan Alcyonidium diaphanum. Water temperature 8.5°C.
Sony NEX-5 in Nauticam housing, 18-55mm lens, SubSee +10 dioptre and 2 x Inon D-2000 flashes.

for more information about this species go to one of the links below
OPK - Opistobranquis nudibranchs of the british isles sea slug forum