Horse-Eye Jack

The horse-eye jack is a large fish; it can grow to a maximum recorded length of 101 cm and a weight of 13.4 kg but is more common at lengths less than 60 cm. The horse-eye jack has a body form similar to other large jacks found throughout its range, with a moderately compressed elongate and deep body. The dorsal profile becomes more strongly curved anteriorly, however the forehead is less blunt than the crevalle jack. The eyes are large in proportion to the rest of the head and covered by a well-developed adipose eyelid, with the posterior extremity of the jaw vertically under or past the posterior margin of the eye. The dorsal fin is in two parts, the first consisting of eight spines and the second of one spine followed by 19 to 22 soft rays. The anal fin consists of two anteriorly detached spines followed by one spine and 16 to 18 soft rays.

The horse-eye jack is commonly found in the subtropical Atlantic Ocean from Bermuda and the northern Gulf of Mexico and south to Rio de Janeiro. In the eastern Atlantic, it is found from St. Paul's Rocks to Ascension Island and, rarely, in the Gulf of Guinea.

It is a pelagic fish. It can be found on reefs and offshore oil rigs. The juvenile can be found closer to shore along sandy and muddy bottoms. The species may venture into brackish waters and can live in river mouths, but it is typically found in saltwater up to 140 m in depth.

The adult horse-eye jack commonly swims with others in a school, either as one species or mixed with crevalle jack. Sometimes it also swims as a pair with a member of a very different species, such as Halichoeres radiatus, a type of wrasse.

The fish is generally wary of scuba divers; it will move slowly away as divers approach. However, schools have been known to crowd around divers, apparently attracted to the bubbles the diver exhales.