Shagrug Nudibranch (Aeolidia papillosa) photographed on a white background. Along with many other aeolid nudibranchs, this species is able to reuse undischarged stinging cells (nematocysts) from the sea anemones that it feeds on, storing them at the tips of the cerata that cover its body for defence. Isle of Skye, Inner Hebrides, Scotland. March.