Fish Identification Photos: Shortjaw Leatherjack, Oligoplites refulgens: The Shortjaw Leatherjack is a possibly the smallest and most seldomly seen member of the Carangidae or Jack Family found in Mexican waters.

The Shortjaw Leatherjack is characterized by its overall “jack-like” appearance, aerodynamic, very slender elongated body, silver color throughout, dark anal fin and yellow caudal and pectoral fins, and characteristic short upper jaw that ends before the rear edge of the eye pupil.

The Shortjaw Leatherjack can be easily confused with the Longjaw Leatherjack, Oligoplites altus (less aerodynamic with a longer jaw extending behind the eye) and the Yellowtail Leatherjack, Oligoplites saurus inornatus (longer jaw with clear anal and dorsal fins, and a yellow caudal fin).

The Jacks are found in all tropical and subtropical seas, with 140 individual species having been identified to date. They are voracious predators feeding primarily on small fishes. They frequently travel in large schools and roam considerable distances, normally following schools of smaller bait fish. They are generally silver in color, and exhibit a wide range in size from about 10 inches and 1 pound, to 6 feet and 90 pounds.

The Shortjaw Leatherjack is pelagic and found in all Mexican waters south of Magdalena Bay including the Sea of Cortez and mainland Mexico, but it appears to be absent around the oceanic islands. It is found in the first 100 feet of the water column over all types of terrain, and is reported to reach a length of 12 inches. They are viewed by locals in southern Baja California as a virtually unknown species.

Shortjaw Leatherjack, Oligoplites refulgens: Shows up when one purchases a “scoop of bait.” Caught in the surf zone, La Playita, San Jose del Cabo, Baja California Sur, Mexico, in December 2003, with a water temperature of 77 degrees, early morning, in 5 to 10-foot deep water, utilizing a net cast by a panguero bait salesmen. Size approximately 6 inches and virtually weightless. This is a very rare, seldom seen, species without a name in the local fishing community. Description and photo courtesy John Snow.