A harmless filefish that copies a toxic puffer closely enough to be mistaken for it by divers.
To about 11 cm, white with four dark saddles and fine brown spotting on the lower body — a close copy of Valentin’s sharpnose puffer, which is toxic. The differences are structural rather than in the pattern: the filefish has a slender first dorsal spine that can be raised above the eye, a longer more flexible body, a distinct second dorsal fin with a soft leading edge, and a narrower snout. In the water the swimming action separates them most reliably, the filefish undulating its dorsal and anal fins while the puffer sculls stiffly.
It is one of the clearest examples of Batesian mimicry on these reefs — an edible species taking on the appearance of a defended one — and the two are often within a few metres of each other. It feeds on algae, small invertebrates and coral polyps over rubble and reef. Recorded from about 2 to 30 m.
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.