A large Red Sea nembrotha with orange rhinophores and gills over a dark body, feeding on colonial sea squirts.
Between about 4.5 and 12 cm; sources disagree, and the larger figures come from divers in the Red Sea and are plausible for an animal of this genus. The ground colour is creamy yellow with black streaks and patches down the back, and there is a bright neon-orange band along each side. The oral tentacles and the foot margin are lined in purple or blue, the gills are deep red grading into purple stalks, and the rhinophores are black with purple or blue sheaths.
Several Indo-Pacific animals of the same genus look similar and how many species there really are is not settled. For this site the answer is simple: this one is confined to the Red Sea, and the neon-orange band along the side identifies it there.
It eats colonial sea squirts, so look for it on ascidian colonies. It lives between about 8 and 35 m and most sightings are on shallow reef. When disturbed it flexes its body from side to side, and it can swim. It regularly rears up to sample the water with its rhinophores.
Ratings are per location: 1 means found on most dives that look for it, 5 means a handful of records. Where enough dives have been logged the figure is calculated from them; otherwise it is an editorial estimate, and says so. We publish habitat and destination, not the dive site.
