Smooth Trunkfish, Lactophrys triqueter

Smooth Trunkfish, Lactophrys triqueter. Fish caught from coastal waters off Marathon, Florida, July 2018. Length: 15 cm (5.9 inches). Catch, photograph and identification courtesy of Eli (obsessiveangling.wordpress.com).

Smooth Trunkfish, Lactophrys triqueter. Fish caught off the Anglin’s Fishing Pier, Lauderdale-by-the-Sea, Florida, March 2015. Length: 20 cm (7.9 inches). Catch, photograph and identification courtesy of George Brinkman, Guelph, Ontario, Canada.

Smooth Trunkfish, Lactophrys triqueter. Fish caught off the Anglin’s Fishing Pier, Lauderdale-by-the-Sea, Florida, November 2014. Length: 22 cm (8.7 inches). Catch, photograph and identification courtesy of Ryan Crutchfield, Tampa, Florida.

Smooth Trunkfish, Lactophrys triqueter. Fish caught from coastal waters off Big Pine Key, Florida, April 2019. Length: 22 cm (8.7 inches). Catch, photograph and identification courtesy of Luke Ovgard, Klamath Falls, Oregon.

Smooth Trunkfish, Lactophrys triqueter. Fish caught off the Anglin’s Fishing Pier, Lauderdale-by-the-Sea, Florida, November 2014. Length: 22 cm (8.7 inches). Catch, photograph, and identification courtesy of Josh Leisen (joshadventures.com), Gaylord, Michigan.

Smooth Trunkfish, Lactophrys triqueter. Underwater photograph taken in coastal waters of Yal-Ku, Quintana Roo, April 2016. Photograph courtesy of Juan Rojo, Akumal.

Smooth Trunkfish, Lactophrys triqueter. Underwater photograph taken in coastal waters off Bonaire, December 2019. Photograph and identification courtesy of Bob Hillis, Ivins, Utah.

The Smooth Trunkfish, Lactophrys triqueter, is a member of the Boxfish or Ostraciidae Family, and is known in Mexico as chapín baqueta. There are three global members in the genus Lactophrys, all three are residents of Mexican waters of the Atlantic Ocean.

The Smooth Trunkfish has an oblong thick body with a humped back and are enclosed in a bony box formed by thickened, joined, enlarged, and hexagonal scale plates. They are brown-black and are covered with numerous small spots that are white, cream or yellow. They have an area with scales on their lower mid-body made up of hexagonal groups of pale spots with a honeycomb pattern. Their fins are yellowish with dark bases and tips. Their eyes and the tip of their snout are black. Juveniles are black with large white or yellow spots. The box has openings for the mouth, eyes, gill slits, fins, and tail. Their body is triangular-shaped being narrow on top and wide at the base. Their head has a pointed snout with protuberant fleshy lips encircling a small mouth that opens in the front and is equipped with small conical teeth and short gill slits. Their anal and dorsal fins are set well back on the body; their caudal fin is fan-like and rounded; and, they do not have pelvic fins. All fins are without spines. Their lateral line is inconspicuous.

The Smooth Trunkfish is a slow swimmer found in and around coral and over sandy seabeds at depths up to 50 m (165 feet). The adults are stationary while juveniles are pelagic and sometimes enter estuaries. They reach a maximum of 47 cm (19 inches) in length. The Smooth Trunkfish is normally found as solitary individuals but can occasionally be seen in small groups. They are protected by a slime coat covering the body that contains ostracitoxin that provides them with defense against predation. It also makes them unsuitable for use in aquariums. They probe the bottom generating a jet stream of water ejected through the mouth to expose benthic invertebrates including acorn worms, mollusks, peanut worms, polychaete worms, and sponges on which they feed. The Smooth Trunkfish is 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 Smooth Trunkfish is a resident of all Mexican waters of the Atlantic Ocean including the Gulf of Mexico and the Caribbean.

The Smooth Trunkfish is similar in size and shape to several other trunkfish. They are most likely confused with the Spotted Trunkfish, Lactoprys bicaudalis, (dark spots covering its body).

From a conservation perspective the Smooth Trunkfish is currently considered to be of Least Concern with stable widely distributed populations. They are of limited interest to most other than to divers as they are visually awesome; they have also been used on a limited basis to make a nice table decor when allowed to dry.