Knoutsodonta depressa (Alder & Hancock, 1842)

7 June, 2015.
East Carr, St Abbs on the east coast.
6 mm animal on the underside of a cobble at 14 metres. Water temperature 9°C.
Sony α6000  in Nauticam housing, Zeiss 50 mm macro lens, Nauticam CMC-1 dioptre 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