Flat Needlefish

Flat Needlefish, Ablennes hians

Flat Needlefish, Ablennes hians. Fish provided by the commercial fishermen of Bahía Kino, Sonora, November 2015. Length: 89 cm (2 feet 11 inches). Photograph and identification courtesy of Maria Johnson, Prescott College Kino Bay Center, Kino Bay, Sonora.

Flat Needlefish, Ablennes hians. Fish caught from coastal waters off Point Palmilla, Baja California Sur, January 2014. Length: 1.0 m (3 feet 3 inches).

Flat Needlefish, Ablennes hians. Fish caught from coastal waters off Cabo Real, Baja California Sur, March 2021. Length: 1.0 m (3 feet 4 inches).

The Flat Needlefish, Ablennes hians, is a member of the Needlefish or Belonidae Family, that is also known as the Barred Needlefish and in Mexico as agujón sable. Globally, this is only species in the genus Ablennes, and it is one of the few species found in Mexican waters of both the Atlantic and the Pacific Oceans.

The Flat Needlefish has a strongly compressed body with green-back, silvery sides, a white belly and anal, caudal and dorsal fins with red tingues. Their back has approximately twelve wide vertical bars on its sides, which are more prominent in juveniles and towards the rear of freshly-caught fish and disappear very quickly post collection. Their head has an elongated jaw with a relatively short beak and their mouth is equipped with an overabundance of sharp needle-like teeth. Their anal, caudal, and dorsal fins are tipped in red. Their eyes are yellow and their beaks are relatively short (16% to 18% of standard length) and feature mid-sized teeth. Their anal has 24 to 28 rays with a concave front lobe and a long base; their caudal fin is concave with equal sized lobes; their dorsal fin has 23 to 26 rays and is large with a concave front lobe and a long base; their pectoral fins have 13 to 15 rays and are concave and short; and, their pelvic fins are long. They do not have gill rakers. They are covered with scales.

The Flat Needlefish is an oceanic pelagic fish found in the first 13 m (40 feet) of the water column. They reach a maximum of 1.20 m (3 feet 11 inches) in length. As of January 1, 2023, the International Game Fish Association world record stood at 4.8 kg (10 lbs 9 oz) with the fish caught in coastal waters off Mozambique in December 1997. The Flat Needlefish is poorly studied with very limited information available about their lifestyle and behavioral patterns including specific details on age, growth, longevity, movement patterns, diet, habitat use, and reproduction.

The Flat Needlefish is a resident of all Mexican waters of the Atlantic Ocean including the Gulf of Mexico and the east coast of the Yucatán Peninsula in the Caribbean. In the Pacific they are found from Cedros Island, Baja California, southward along the central and southwest coasts of Baja, throughout the Sea of Cortez, and along the coast of the mainland from Mazatlán, Sinaloa, south to Guatemala.

The Flat Needlefish cannot be confused with any other Needlefish due to the black bars found on the sides of live fish and to their flat bodies.

From a conservation perspective the Flat Needlefish is currently considered to be of Least Concern with stable, widely distributed populations. Globally it is fished commercially at a minor level being caught with lures and seines. In Mexican waters it is viewed by locals as a pest with “too many green colored bones” to be utilized for food. They are either a “catch and release” or retained for use as cut bait for bottom fishing. When hooked they like to make mad, short dashes. They are excellent bait stealers inflicting major damage to and weakening monofilament lines with their many teeth.