Nudibranch - Phyllidia varicosa
Native to the Indo-West Pacific Oceans including the central Pacific and the Red Sea, Phyllidia varicosa (Nudibranchia - Phyllidiidae) is probably on of the sea slugs most frequently noticed by divers.
It can be distinguished by its elongate-oval body with three to six longitudinal, blue-gray ridges composed of smooth, yellow-capped tubercles.
Photo credit: ©Jan Messersmith | Locality: Madang, Papua New Guinea
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