Limacia clavigera (Müller, 1776)

9 July, 2014.
Lephinchapel, Loch Fyne on the west coast. 
22 mm animal on kelp at 6 m. Water temperature 12°C.
Sony α6000  in Nauticam housing, 30 mm 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