Houndfish, Tylosurus crocodilus
Houndfish, Tylosurus crocodilus, Juvenile. Fish caught from coastal waters off Melbourne, Florida, January 2022. Length: 48 cm (19 inches). Catch, photograph and identification courtesy of James Lafontaine, Long Island, New York.
Houndfish, Tylosurus crocodilus. Fish caught from coastal waters off Ft. Lauderdale, Florida, January 2022. Length: 62 cm (2 feet 0 inches). Catch, photograph and identification courtesy of Ben Cantrell, Sebastian, Florida.
The Houndfish, Tylosurus crocodilus, is a member of the Needlefish or Belonidae Family, and are also known as the Crocodile Needlefish and the Hound Needlefish and in Mexico as aguja, agujón del Atlántico and marao ojón. There are six species in the genus Tyosurus of which two are found in Mexican waters of the Atlantic Ocean and one in the Pacific Ocean. The Giant Mexican Needlefish, Tylosurus fodiator, found in Mexican waters of the Pacific was historically considered to be a subspecies of Tylosurus crocodilus, until it recently became a standalone species.
The Houndfish has a very elongated slender, rounded body with a stout, straight, beak that has extremely elongated jaws that form a long upcurved beak that is equipped with numerous long needle-like teeth. They have a dark green upper body that transitions to dark blue and then to silver ventrally. This countershading affords them camouflage to avoid predation. Their anal fin is elevated and has 19 to 22 rays; their caudal fin is slightly forked with a much longer lower lobe; their caudal peduncle has a prominent raised black keel; their dorsal fin originates slightly in front of the anal fin and is elevated and has a long base with 21 to 25 rays; their pectoral fins have 13 to 15 rays; and, their pelvic fins are relatively long. Their body is covered with scales before the dorsal fin. They do not have gill rakers. Juveniles have an elevated black low on the posterior of their dorsal fins and are unique amongst the needlefish with teeth than point backwards.
The Houndfish are found in the first 10 m (33 feet) of the water column. They are the largest member of the family and reach a maximum of 1.5 m (5 feet 11 inches) in length and 6.4 kg (14 lbs 1 oz) in weight. As of January 1, 2024, the International Game Fish Association world record stood at 4.88 kg (10 lbs 12 oz), with the fish caught from coastal waters off Nassau, Bahamas, March 2013. The Houndfish is an epipelagic species that is common surface coastal waters near jetties, piers, and reefs that is found offshore on occasion either as solitary individuals or in small schools. Adults are voracious predators feeding primarily on fish and limited amounts of crustaceans. Reproduction is oviparous with females laying approximately 3,500 large spherical eggs which attach themselves to floating vegetation.
The Houndfish 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.
The Houndfish can be confused with the Atlantic Agujón, Tylosurus acus (slender, curved long beak; long anal and dorsal fin lobes), the Flat Needlefish, Ablennes hians (body compressed; 12 black bars on the sides; caudal fin concave) and the Giant Mexican Needlefish, Tyosurus fodiator (virtually identical but a resident of the Pacific Ocean).
From a conservation perspective, the Houndfish is currently considered to be of Least Concern, with stable, widely distributed populations. They are currently considered to be Tarumatogenic due to their size, massive numbers of teeth and their habit of breeching near boats than can cause puncture wounds in humans they should be considered and handled as very dangerous animals. In some regions they are fished and sold commercially, normally at night with the aid of artificial lights, with purse seines and drift nets. However, their meat is green significant diminishing their value. They are also pursued by recreational anglers being caught on live bait or surface lures.