Aeolidia papillosa (Linnaeus, 1761)

10 April 2013.
Inverkip Pier, Firth of Clyde on the west coast.
55 mm animal at 6.5 m. Water temperature 7° C.
Sony NEX-5 in Nauticam housing, 18-55mm lens 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