Onchidoris bilamellata

Onchidoris bilamellata (Linnaeus, 1767)

1 October, 2011.
East Coast Reef, Hyskeir on the west coast.
Part of a large group of animals at 20 metres in 13°C water. There were many such aggregations observed between 16 - 24 metres throughout this dive.
Sony NEX-5 in Nauticam housing, 18-55mm lens, SubSee +10 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