Adalaria proxima (Alder & Hancock, 1854)

27 October, 2002.
Port an Mine, Loch Etive on the west coast. 
Found on kelp blade at 4 metres in 12° C water, a 10mm long animal.
Nikon 90SX with 60mm lens in Subal housing and housed SB26 flash

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