Sea Wonder: Golden Smooth Trunkfish

The golden smooth trunkfish is a jewel of the national marine sanctuary system. It is a variety of smooth trunkfish that exists only in two places in the world, one of which is Flower Garden Banks National Marine Sanctuary.

Appearance

Smooth trunkfish (Lactophrys triqueter) are triangular shaped fish with an average length of eight inches and a maximum length of 19 inches. Smooth trunkfish belong to the Boxfish family, with several species found in the tropical Western Atlantic. Their tails look feathered like brushes and their snout is long and pointed, ending with lip-like structures and a small mouth. Due to their bulky shape and rigid exterior, they aren’t the best swimmers. 

Their coloration is generally dark — especially around the eyes and mouth — with white spots. However, the golden smooth trunkfish is unique in that it is yellow in color with white spots. Both species have a bony armor for defense and honeycomb markings on their mid-body. Scientists don’t yet know what causes the color difference between these two populations of the same species, but the golden version is much more of a rarity than its darker counterpart. 

Habitat

Smooth trunkfish call home coral reefs and sandy seabeds at a depth of around 50 meters. They prefer warmer waters between 72 and 79 degrees F. Their range in the western Atlantic Ocean is as far north as Canada and as far south as Brazil, including waters in the Caribbean, Gulf of Mexico, and Bermuda. While you might find smooth trunkfish in Florida Keys National Marine Sanctuary, the golden smooth trunkfish is only found in Flower Garden Banks National Marine Sanctuary and the Bay Islands in Honduras! 

Diet & Life History

The smooth trunkfish is generally a solitary animal, though we sometimes see them traveling together in small groups for short periods of time. They feed on invertebrates like mollusks, worms, crustaceans, algae, and sponges by pushing jets of water from their mouths and disrupting the sands and sediments in which their targets live. 

In addition to their hard exterior, smooth trunkfish can produce a toxin through their body mucus that is used for defense. 

Threats and Conservation

Golden smooth trunkfish are not generally fished for human consumption on a large scale, and their populations are considered healthy across their range. However, overfishing, habitat destruction, coral bleaching events, warming ocean temperatures, and ocean acidification all affect the species and their prey.