Rough Triggerfish

Rough Triggerfish, Canthidermis maculata

The Rough Triggerfish, Canthidermis maculata, whose common Spanish name is Cochito Manchado, is a member of the Triggerfish or Balistidae Family, known collectively as “Cochitos” in Mexico. The Rough Triggerfish is also knows as the Spotted Oceanic Triggerfish.

The Rough Triggerfish have elongated (45-47% of standard length), robust, compressed, and oblong bodies that 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 eight 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 caudal fin is doubly concave; their dorsal fin has three spines, the first of which can be locked erect and the second being one-half the size of the first; 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 are normally only observed around floating debris such as logs but have been found at depths up to 360 feet. They reach a maximum length of 50 cm (20 inches) and weigh up to 2.4 kg (5.2 pounds). They are found from Acapulco 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, extending the known northerly range for this species. They are a rare, deep water species and little is known about their behavioral patterns.

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

The Rough Triggerfish are exceedingly rare and therefore of limited interest.

Rough Triggerfish, Canthidermis maculata: Fish caught off the surface 10 miles north of Puerto Los Cabos, Baja Californa Sur, October 2003, with a hoop net. It was a part of a massive school mixed about 50:50 with Pacific Tripletails, Lobotes pacificus, under a very large floating tree. The fish were brought to the surface and became “balled up” in a group of about 500, fighting over chummed sardines. Size: 25 cm (10 inches). Fish identification courtesy of Dr. Ross Robertson, Smithsonian Tropical Research Institute, Panama.Rough Triggerfish, Canthidermis maculata: Fish caught off the surface 10 miles north of Puerto Los Cabos, Baja Californa Sur, October 2003, with a hoop net. It was a part of a massive school mixed about 50:50 with Pacific Tripletails under a very large floating tree. The fish were brought to the surface and became “balled up” in a group of about 500, fighting over chummed sardines. Length: 25 cm (10 inches). Fish identification courtesy of Dr. Ross Robertson, Smithsonian Tropical Research Institute, Panama.

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