Giant Mexican Needlefish, Tylosurus fodiator

Giant Mexican Needlefish, Tylosurus fodiator. Fish caught off the beach, at Km 21, Cabo Real, Baja California Sur, October 2006.  Length: 84 cm (2 feet 9 inches).

Giant Mexican Needlefish, Tylosurus fodiator. Fish caught from coastal waters off Cabo San Lucas, Baja California Sur, August 2004.  Length: 1.8 m (5 feet 10 inches).

Giant Mexican Needlefish, Tylosurus fodiator. Fish caught from the beaches of Cabo San Lucas, Baja California Sur, October 2018.  Length: 1.8 m (5 feet 10 inches). Photograph courtesy of Dr. John Warner, Colorado Springs, Colorado and caught with guide Martin Almazan.

The Giant Mexican Needlefish, Tylosurus fodiator, is a member of the Needlefish or Belonidae Family, that is also known as the Crocodile Needlefish, the Houndfish, and the Mexican Needlefish and in Mexico as agujón lisero and marao lisero. Globally, there are six species in the genus Tylosurus, of which three are found in Mexican waters, one, this species, in the Pacific and two in both the Atlantic and Pacific Oceans.

The Giant Mexican Needlefish has a slender elongated rounded body with a dark blue-green upper body, silvery sides, and a white belly with a black keel at the base of the caudal fin. They have large eyes and their jaws are relatively short, stout and straight.; their beaks are equipped with many long and pointed teeth. Their anal fin has 17 or 18 rays; their caudal fin is slightly forked with the lower lobe being longer than the upper lobe; their dorsal fin has 18 to 22 rays and a long base; their pectoral has 14 or 15rays; and, their pelvic fins are relatively long.

The Giant Mexican Needlefish is an oceanic pelagic fish found in the first 10 m (33 feet) of the water column that can also can be found close to shore. Scientifically they reach a maximum of 1.34 m (4 feet 3 inches) in length and 9.9 kg (21 lbs 13 oz), however both fishes above illustrate that they get much longer. The are various predators that feed primarily on small silvery fishes. Reproduction is oviparous and their eggs can be found attached to floating debris being attached my tendrils. The Giant Mexican Needlefish is rare and 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 Giant Mexican Needlefish is a resident of Mexican waters of the Pacific Ocean and is found from Guerrero Negro, Baja California, throughout the Sea of Cortez, and along the coast of the mainland south to Guatemala.

The Giant Mexican Needlefish is most likely confused with the California Needlefish, Strongylura exilis (yellow eyes and fins, thin body profile, anal fin before the dorsal fin), the Pacific Needlefish, Tylosurus  pacificus (short beak, massive teeth, long pectoral and pelvic fins) and the Keeljaw Needlefish, Tylosurus melanotus (keel on tip of chin).

Caudal fins. Top photo Giant Mexican Needlefish, Tylosurus fodiator. Bottom photo Pacific Needlefish, Tyosurus pacificus.

From a conservation perspective the Giant Mexican Needlefish is currently considered to be of Least Concern with stable, widely distributed populations. They are fished commercially regionally, sold fresh or salted, and prone to overfishing. They are considered to be traumatogenic, being capable of inflicting serious wounds in humans with their teeth. When hooked they become acrobatic, making spectacular jumps while bending themselves into complete circles, and make mad, short dashes. They are excellent bait stealers inflicting major damage to and weakening monofilament lines with their enormous teeth.