Spiny Boxfish
Cofre Espinoso
(Lactoria diaphana)

Spiny Boxfish, Lactoria diaphana: The Spiny Boxfish has an oblong thick body that is enclosed in a bony box formed by thickened, joined, enlarged, hexagonal scale plates.

They are gray to pale brown in color with indistinct dark blotches.

They have wide round bellies with five longitudinal ridges and five spines.

The box has openings for the mouth, eyes, gill slits and fins and tail base. The mouth is a small opening at the front with fleshy lips. The gill openings are short, oblique slits in front of the pectoral base.

They have no dorsal spines, the anal and dorsal fins are at the rear, and they have no pelvic fins.

The Spiny Boxfish are found in the first 150 feet of the water column around coral and rocky reefs; the adults are stationary while the juveniles are pelagic. They reach a maximum length of 34 cm (13.4 inches). They are unique in appearance and cannot be confused with other species.

In Mexican waters the Spiny Boxfish has a limited distribution being found only along both coasts of Baja.

The Spiny Boxfish is a member of the Ostraciidae Family which includes Boxfishes and Cowfishes, known in Mexico as peces cofre. This family consists of 14 genera and 33 species globally of which only two are found in Mexican waters. They are slow swimmers and characterized by having bodies that consist of rectangular boxes made up of bony plates. The body and the small fins do not have spines and they do not have pelvic fins. They have a social structure consisting of a harem of three or four females and one male. They are protected by a toxic slime that can kill other fishes making them unsuitable for use in aquariums. They feed on algae, soft corals, crustaceans, sponges, truncates, and worms.

Spiny Boxfish picture

Spiny Boxfish picture

Spiny Boxfish, Lactoria diaphana: A rare collection provided by the commercial fishermen of the greater Los Cabos area, Baja California Sur, Mexico, in September 2011. Size 14.4 cm (5.7 inches). Description and photos courtesy of John Snow.