Dendronotus frondosus (Ascanius, 1774)

18 June, 2014.
Eagle Rock, the Garvellachs on the west coast.
20 mm animal at 18 m. Water temperature 11°C.
Sony NEX-5 in Nauticam housing, Zeiss 50 mm macro 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