Tilefishes are mostly small perciform marine fish comprising the family Malacanthidae. They are usually found in sandy areas, especially near coral reefs. Commercial fisheries exist for the largest species, making them important food fish. However, the U.S. Food and Drug Administration warns pregnant or breastfeeding women against eating tilefish and some other fish due to mercury contamination. Exceptionally colorful smaller species of tilefish are favored for aquariums. Taxonomic issues The family is further divided into two subfamilies: Latilinae, sometimes called the Branchiosteginae, and Malacanthinae. Some authors regard these subfamilies as two evolutionarily distinct families. The placement of this family within the Eupercaria is still not certain. The 5th Edition of Fishes of the World classifies them within the Perciformes but in a grouping of seven families which may have a relationship to Acanthuroidei, Monodactylidae, and Priacanthidae. while other authorities place it outside the Perciformes, at an order level but with its true relationships being incertae sedis. Subfamilies and genera The following two subfamilies and five genera are classified within the family Malacanthidae, in total it contains 45 species. subfamily Latilinae Gill, 1862 genus Branchiostegus Rafinesque, 1815 genus Caulolatilus Gill, 1862 genus Lopholatilus Goode & Bean, 1879 subfamily Malacanthinae Poey, 1861 genus Hoplolatilus Günther 1887 genus Malacanthus Cuvier 1829 Description The two subfamilies appear to be morphologically different, with members of the Latilinae having deeper bodies bearing predorsal ridge and heads rounded to squarish in profile. In contrast, members of the Malacanthinae are more slender with elongated bodies lacking predorsal ridge and rounded head. They also differ ecologically, with latilines typically occurring below 50 m and malacanthines shallower than 50 m depth. Tilefish range in size from (yellow tilefish, Hoplolatilus luteus) to (great northern tilefish, Lopholatilus chamaeleonticeps) and a weight of . Both subfamilies have long dorsal and anal fins, the latter having one or two spines. The gill covers (opercula) have one spine which may be sharp or blunt; some species also have a cutaneous ridge atop the head. The tail fin may range in shape from truncated to forked. Most species are fairly low-key in colour, commonly shades of yellow, brown, and gray. Notable exceptions include three small, vibrant Hoplolatilus species: the purple sand tilefish (H. purpureus), Starck's tilefish (H. starcki), and the redback sand tilefish (H. marcosi). Tilefish larvae are notable for their elaborate spines. The family name Malacanthidae, is based on the type genus Malacanthus which is