Cowfish

Dark markings on head and body; parallel bands on cheek. Pair of prominent spines projecting from in front of eyes suggests cow horns. Second pair of spines at lower rear corners of cuirass (Ref. 26938). Body deep, covered with hexagonal dermal plates (Ref. 37521).

Dorsal spines (total): 0; Dorsal soft rays (total): 10; Analspines: 0; Analsoft rays: 10

Occurs in shallow waters, mainly over seagrass beds (Ref. 33, 3696). Found in shallow water down to about 80 m (Ref. 3696). Feeds on sessile invertebrates such as tunicates, gorgonians and anemones, as well as on slow-moving crustaceans, sponges (Ref. 3696), hermit crabs and marine plants (Ref. 13442).

Found in shallow water down to about 80 m, mainly in seagrass beds (Ref. 3696). Feeds on sessile invertebrates such as tunicates, gorgonians and anemones, as well as on slow-moving crustaceans, sponges (Ref. 3696), hermit crabs and marine plants (Ref. 13442). Oviparous (Ref. 205). Considered an excellent food fish; marketed fresh (Ref. 3696).

fisheries: minor commercial; aquarium: commercial; price category: high; price reliability: very questionable: based on ex-vessel price for species in this family

Acanthostracion quadricornis (Linnaeus)

The sections of A 2 are well separated, and there are two fiber directions in A 2α. A 1β″ is well separated from the more ventral fibers, but the other two portions are scarcely distinct. The anterior bundle of fibers of the retractor arcus palatini is well developed. The dilatator operculi has an entirely tendinous insertion on the tip of the dorsal process of the opercle, and the levator arcus palatini is well developed.

The dorsolateral half of the protractor hyoidei passes lateral to the interopercle to insert on the dentary.

The interradialis partly overlies the tendons of the hypochordal longitudinalis, and the transversus caudalis inserts on rays V 3–5. The flexor dorsalis superior and the flexor ventralis inferior are better developed than in O. tuberculatus.

The epaxialis and the obliquus superioris insert on the middle eight caudal fin rays (D 1–4 and V 1–4), there being no tendons to D 5 or V 5.

The swim bladder musculature differs from O. tuberculatus. The lateral and more posterior fibers pass dorsally and medially from their insertion on the anterodorsal surface of the swim bladder to their origin on the dorsolateral face of the vertebral column. Anteriorly, the fibers tend to curve ventrally and then posteriorly from their origin on the vertebrae, and lie medial to the outer, more posterior fibers. This leaves a gap between the ventromedial surfaces of the transverse posterior fibers and the dorsolateral surface of the anterior and more longitudinal fibers, giving rise to the “hollow ball of muscles” (Tyler, 1963b:159).

Summary of Ostraciidae

The main variation in this family is found in the jaw and caudal fin musculatures. In the former, the differences involve mainly the degree of subdivision of the adductor mandibulae, while in the latter most variation is seen in the sites and number of rays involved in the insertion of the hypochordal longitudinalis and transversus caudalis. Apart from this, this family is conservative in its myology.

Myological Description of the Representative Triodontid

The outline of Triodon, the monotypic representative of this family, is given in Figure 7. The species inhabits the deeper waters (150–300 meters) of the continental shelves of the Indo-Pacific. Almost nothing is known of the life history and habits of this rare fish. Of the four specimens dissected for this study, only one had anything in its gut. This specimen (270 mm SL) contained the remains of a number of echinoids (?Clypeasteroidea), with occasional carapaces of shrimplike crustaceans. The lunate caudal fin, slender peduncle, and poorly developed dorsal and anal fins suggest that Triodon is a fairly fast swimmer, but there is no direct evidence. The pelvic girdle is represented by a long, shaftlike bone, very similar to that of the balistoids. The jaws are massive and beaklike, and form a powerful crushing apparatus, as they do in all the remaining families except the Canthigasteridae (although even here the basic plan remains).

Triodon is usually considered to be the pleisomorph member of the gymnodonts (e.g., Tyler, 1962c), and to form a morphological intermediate between them and the triacanthoids + balistoids + ostracioids.

The scrawled cowfish (Acanthostracion quadricornis) is a species of boxfish native to the western tropical and equatorial Atlantic, as well as the Gulf of Mexico. They range in size from 8–15 inches (20–38 cm), with a maximum length of 18 inches (46 cm), and can be found at depths between 6 and 80 feet (1.8 and 24.4 m). It is common to occasional in Florida and Bahamas; occasional to uncommon in the Caribbean. It also occurs in the Gulf of Mexico, north to Massachusetts, Bermuda and south to Brazil in tropical and warm temperate waters.

Western Atlantic: Massachusetts (USA), Bermuda, and northern Gulf of Mexico to southeastern Brazil