The orange spotted filefish or harlequin filefish, Oxymonacanthus longirostris, is a filefish in the family Monacanthidae found on coral reefs in the Indo-Pacific Oceans. The orangespotted filefish is a different species and refers to Cantherhines pullus.
The orange spotted filefish is pale blue with about eight longitudinal rows of orange-yellow patches. In the wild it feeds almost exclusively on Acropora polyps.
They are often offered for sale in the aquarium trade, but few survive long in captivity. They are difficult to maintain in an aquarium unless provided with live corals. They must be kept in species-specific tanks, or tanks with very passive tankmates such as seahorses or pipefish. They have been successfully bred in captivity.