Onchidoris muricata (Müller, 1776)

April, 2001.
At Sgeir a Phuirt on Canna in the Small Isles on the west coast. 
At 18 metres in 7° C water, spawn in the vicinity of several animals.
Taken using a Nikon 90SX with 105mm lens in Subal housing and housed SB26 flash.

for more information about this species go to one of the links below

nudibranchs of the british isles sea slug forum