Rough Triggerfish

Rough Triggerfish, Canthidermis maculata

Rough Triggerfish, Canthidermis maculata, Juvenile. Fish provided by the commercial fishermen of the greater Los Cabos area, Baja California Sur, October 2009. Length: 5.8 cm (2.3 inches). Identification courtesy of H.J. Walker, Jr., Scripps Institution of Oceanography, La Jolla, California.

Rough Triggerfish, Canthidermis maculata. Fish caught from coastal waters off Ardita, Colombia, June 2019. Length: 30 cm (12 inches). Catch, photograph and identification courtesy of Chris Wheaton, Fullerton, California.

Rough Triggerfish, Canthidermis maculata. Fish caught from coastal waters off Key West, Florida, August 2014. Length: 33 cm (13 inches). Catch and photograph courtesy of Dean Kimberly, Atlanta, Georgia.

Rough Triggerfish, Canthidermis maculata. Fish caught from coastal waters of Mazatlán, Sinaloa, October 2012. Length: 36 cm (14 inches). Catch and photograph courtesy of George Brinkman, Guelph, Ontario, Canada.

Rough Triggerfish, Canthidermis maculata. Fish caught from oceanic waters in the Central Pacific (2oN, 140oW), October 2015. Length: 44 cm (17 inches). Catch and photograph courtesy of Dan Fuller, San Diego, California.

Rough Triggerfish, Canthidermis maculata. Fish caught from coastal waters off  Vanuatu, October 2012. Length: 46 cm (18 inches). Catch, photograph and identification courtesy of George Brinkman, Guelph, Ontario, Canada.

Rough Triggerfish, Canthidermis maculata. Underwater photograph taken in coastal waters off Kailua-Kona, Hawaii, November  2015. Photograph courtesy of Bob Hillis, Ivins, Utah.

The Rough Triggerfish, Canthidermis maculata, is a member of the Triggerfish or Balistidae Family, that is also known as the Spotted Oceanic Triggerfish and in Mexico as cochito manchado. There are three global members of the Canthidermis Genus, all three of which are found in Mexican waters, one in the Atlantic, one in the Pacific and one in both the Atlantic and Pacific Oceans.

The Rough Triggerfish have elongated robust, compressed, and oblong bodies with a depth that is 44% to 48% of standard length. They are black to grayish dark blue and are covered with small white spots. Their head has a rounded profile, modest-sized eyes, a small mouth that opens at the front, and powerful jaws with 8 heavy human-like teeth on the upper and lower jaws. Their anal fin and second dorsal fin are long and curved and their anterior rays are very elevated and much longer than their posterior rays. Their anal fin has 20 to 22 rays; their caudal fin is doubly concave; their first dorsal fin has 3 spines, the first of which can be locked erect and the second being one-half the size of the first; their second dorsal fin has 23 to 25 rays; their pectoral fins have 13 to 15 rays; and, their pelvic fins are minute. They have thick leathery skin.

The Rough Triggerfish are an ocean pelagic species that is normally found far out at sea. They collect around floating debris such as logs but have been found at depths up to 110 m (360 feet). They reach a maximum of 50 cm (20 inches) in length and 2.4 kg (5.2 lbs) in weight. As of January 1, 2023, the International Game Fish Association world record stood at 1.02 kg (2 lbs 4 oz) with the fish caught in coastal waters off the Kona Coast, Hawaii in May 2011. The Rough Triggerfish is  a rare, deep water , and 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 Rough Triggerfish is a resident of all Mexican waters of the Atlantic Ocean including the Gulf of Mexico and the Caribbean. In the Pacific they are found from Acapulco, Guerrero south along the coast of the mainland to Guatemala and around all the oceanic islands. I have caught a fish that was about 10 miles north of La Playita and 30 miles into the Sea of Cortez, and have juveniles collected off the southwest coast of Baja extending the known northerly range for this species.

The Rough Triggerfish is an easy fish to identify and cannot be confused with any other species.

From a conservation perspective the Rough Triggerfish is currently considered to be of Least Concern with stable, widely distributed populations. They are exceedingly rare and therefore of limited interest.