Ostraciidae is a family of squared, bony fish belonging to the order Tetraodontiformes, closely related to the pufferfishes and filefishes. Fish in the family are known variously as boxfishes, cofferfishes, cowfishes and trunkfishes.

Ostraciidae occupy the Atlantic, Indian, and Pacific oceans, generally at middle latitudes, although the common or buffalo trunkfish (Lactophrys trigonus) which lives mainly in Florida waters may be found as far north as Cape Cod. The cowfish variety Lactophrys quadricornis can grow to be 50 cm or less in size, but are generally smaller at higher latitudes.

They come in a variety of different colors, and are notable for the hexagonal or “honeycomb” patterns in their skin and skeletons. They swim in a rowing manner. The hexagonal plate-like scales of these fish are fused together into a solid, triangular, box-like carapace, from which the fins and tail protrude. Young Ostraciidae are more rounded in shape and may exhibit bright colors. Because of these heavy armoured scales, Ostraciidae are limited to slow movements, but few other fish are able to eat the adults. Ostraciidae of the Genus Lactophrys also secrete poisons from their skin into the surrounding water, further protecting them from predation.^[1]

(From Wikipedia, July 9th, 2010)

—

Inhabits deep coastal slopes and sheltered muddy substrates, usually in deep water offshore, but occasionally shallow near seagrass beds with silty rubble substrates (Ref. 48637). Usually occurs in sandy bottoms in coastal waters. Feeds on benthic invertebrates. Generally considered as trash fish; not consumed.

(From EOL via FishBase)