Houndfish, Tylosurus cocrodilus
The Houndfish, Tylosurus crocodilus, whose common Spanish name is agujón lisero, is the largest member in the family Belonidae, the Needlefishes, known as agujónes in Mexico. It is also known as the Crocodile Needlefish and the Giant Mexican Needlefish. Globally, there are only six species in the genus Tylosurus, of which three are found in Mexican waters, two in both the Atlantic and the Pacific and one in just the Pacific. This is one of the few species found in Mexican waters of both oceans.
The Houndfish have slender elongated rounded bodies with a dark blue-green upper body, silvery sides, and a white belly. They have large eyes and their beaks are stout, straight, of modest equal lengths (16-18% of standard length), and equipped with many very large, long, and pointed teeth. Their caudal fin is lunate with the lower lobe being much longer than the upper lobe. Their pectoral and pelvic fins are relatively long.
The Houndfish are an oceanic pelagic fish found in the first ten feet of the water column. They reach a maximum length of 162 cm (64 inches) and a maximum girth of 41 cm (16 inch), as documented by a fish that was caught off the beach near La Paz by Neil Kelly. They travel in large massive schools showing up in a chum line and can be taken as a by-catch on live bait. They are finicky eaters that like to play with their food and are difficult to hook. They are more inshore than other Needlefish; if you catch a Needlefish off the beach it will most likely be this species. They are found in all Mexican waters of the Pacific, with the exception of waters north of Cedros Island along the west coast of Baja. They are a poorly studied species and very little is known about their behavioral patterns.
The Houndfish can be easily confused with the California Needlefish, Strongylura exilis (yellow eyes and fins, thin body profile) and the Pacific Agujón, Tylosurus pacificus (long up-curved beak, forked caudal fin, short pectoral fins).
The Houndfish are viewed by locals as a pest with “too many 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 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.