Uncommon in the Solitary Islands Marine Park. Distributed throughout the tropical Indo-Pacific generally including the Red Sea. In Australia recorded from Perth through the tropical north to northern New South Wales and Lord Howe Island.
Frequent coral and rocky reef, thought to feed on dark orange/red sponge Higginsia massalis, among others. Depth range to at least 30 m.
Colour variable from yellow to dark orange, with from 4 to 10 black circles with a yellow or white tubercle in the centre. All forms have a row of large tubercles running down the midline of the mantle. Grows to 60 mm long.
Gary Cobb, David Mullins, Nudibranchs Encyclopedia, 2nd Edition, 2015. Publishers Thomas Slone, Masalai Press and Tim Hochgrebe, Underwater Australasia. p.255.
Australian Museum, Sea Slug Forum. http://www.seaslugforum.net/showall/phylocel. Accessed 25/09/2018.