The ground colour of the fused mantle lobes is usually lilac-grey or some shade of buff, but brighter colours such as orange occur. Colour and patterning are extremely variable on the dorsal surface, which often has marks of white, orange, yellow, black, and/or red that may cover almost all the ground colour. The marks may resemble sessile animals in the vicinity; the right hand specimen has some marks resembling barnacles. It also has a white penis protruding from its anterior. Lengths 21 mm and 11 mm. Menai Strait, Wales. March 2011 & June 2013.