Doris pseudoargus (Rapp, 1827)

18 April, 2014.
Inverkip Pier, Firth of Clyde on the west coast.
45 mm animal in the centre at 8 m. There were many mating pairs, singles and spawn masses on this and adjacent pier legs. Water temperature 8° 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