A small snail on sea fans and sea plumes. The orange leopard pattern is on the living mantle drawn over the shell, not on the shell, which is plain cream underneath.
Shell to 45 mm, typically 25 to 35. The important thing to tell a diver is that the pattern everyone photographs is on the living mantle, not on the shell. The mantle is bright orange-yellow with black-outlined polygonal spots, and it is withdrawn into the shell when the animal is disturbed. The shell underneath is plain cream, white or pale orange, smooth and glossy, with a raised ridge across the back. A flamingo tongue with its mantle in looks like nothing at all.
Two similar animals are usually named as separate species: one has open black lines rather than closed rings, the other is smaller with dark-centred spots. Closed rings mean this one. A 2017 genetic study found the three are not distinct, so they may be pattern forms of a single species. Describe what you saw rather than committing to a name.
It feeds only on sea fans and other gorgonians, scraping the polyps off with its rasping tongue and leaving pale feeding scars along the branch. It sits directly on its food, in the open, in daylight, and it stores the gorgonian’s chemical defences for its own use. It lives between about half a metre and 30 m and has been recorded to 90.
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.