Cuthona nana (Alder & Hancock, 1846)

14 December, 2014.
Ardcastle, Loch Fyne on the west coast.
6 mm animal with spawn on a hermit crab shell at 19 metres. Water temperature 10.5°C.
Sony α6000  in Nauticam housing, 50 mm Zeiss Touit 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