Phyllodesmium macphersonae (Burn, 1962)
Possibly common throughout the Solitary Islands Marine Park. Distributed through the tropical Indo-West Pacific region. In Australia recorded from all states including Victoria and Tasmania.
Usually found on rocky reef in relatively shallow waters where it feeds on undetermined species of octocorals.
Specimen pictured discovered in shallow rock pool. This species retains symbiotic zooxanthellae in its body which provides a food source for the animal. "The brown patches which form such a prominent element of its colour pattern are in fact 'gardens' of zooxanthellae, arranged in special branches of the digestive system, so that they are able to get sufficient sunlight for photosynthesis. Grows to 15 mm.
Gary Cobb, David Mullins, Nudibranchs Encyclopedia, 2nd Edition, 2015. Publishers Thomas Slone, Masalai Press and Tim Hochgrebe, Underwater Australasia. p.224.
Australian Museum, Sea Slug Forum. http://www.seaslugforum.net/find/phylmacp. Accessed 25/09/2018.