Facelina auriculata (Müller, 1776)

8 August, 2015.
Skelly's Hole, St. Abbs on the east coast.
18 mm animal at 12 metres. Water temperature 13°C.
Sony α6000  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