Billfish Family Photos and Information – Istiophoridae

The Billfish Family – Istiophoridae

Striped Marlin, Kajikia audax, a representative member of the Billfish or Istiophoridae Family. Photo courtesy of Marc Montocchio (, Morehead City , NC.

The fish of the Billfish or Istiophoridae family include the marlins, sailfish, and spearfish. Globally there are eleven known Istiophoridae that have been placed in five genera of which eight are found in Mexican waters, three in the Atlantic, three in the Pacific, and two that reside in both the Atlantic and the Pacific. All are large, oceanic, pelagic surface fish found in the upper layer of the water column in tropical and subtropical waters. In Mexico they are known as picudos. They all have long compressed bodies with a prolonged upper bill that forms a long spear with a rounded cross section, which is used as a spear to attack and stun prey. Their mouth is not protrusible and is equipped with fine, rasp-like teeth on both jaws. They have wide gill openings without gill rakers and double keels at the base of their strongly forked tail. Their first dorsal fin typically has a tall front lobe and a long base that is quite low and ends very close to the origin of the much smaller second dorsal fin. Their anal and dorsal fin can be depressed into grooves. Their caudal fins are large, strong, and forked. They have short and narrow pelvic fins and visible lateral lines. They are covered with narrow pointed scales.

The Billfish are generally blue on their back and upper sides and transition to silvery white ventrally. Some species have horizontally aligned spots or longitudinal lines on their body and/or black spots on their first dorsal fin membrane. They are voracious predators that follow schools of smaller fish and squid upon which they prey. They are very fast swimmers and some even migrate across oceans. They reach a maximum length of 4.0 meters (13 feet 1 inch).

The Billfish are renowned and prized gamefish pursued for their large size and fighting abilities with hundreds of millions of dollars spent each year by recreational anglers in their pursuit. Many billfish are caught commercially by longliners and sold primarily in Japan commanding high prices. However, none of these fish are considered “good eating” and we strongly urge that as many fish as possible be handled as “catch and release.”

There are currently five members of the Billfish Family presented in this website:

Black Marlin, Istiompax indica
Blue Marlin, Makaira nigricans
Sailfish, Istiophorus platypterus

Shortbill Spearfish, Tetrapturus angustirostris
Striped Marlin, Kajikia audax