Thornback Cowfish

Lactoria fornasini

Thornback Cowfish (Lactoria fornasini) is a small tropical boxfish with a rigid, boxy body and long horns, found on sheltered reefs, lagoons, and sandy seagrass flats. It is not a typical target for anglers and is best treated as a reef species of interest rather than a game fish.

Saltwater

Thornback Cowfish reference image — Rickard Zerpe, cc-by, via Wikimedia Commons. Source: Wikimedia Commons.

Identification points

Rigid, box-shaped body covered with hard bony plates
Two long forward-pointing horns above the eyes and additional rearward projections
Yellowish to tan body often marked with small dark spots or reticulations

Habitat

Shallow tropical marine habitats, especially sheltered coral reefs, reef edges, lagoons, seagrass beds, and sandy areas near structure; usually close to the bottom.

Bait notes

Not commonly targeted. If encountered by anglers, it may peck at very small natural baits like bits of shrimp, squid, or worm on light tackle, but it is best regarded as a bycatch species.

Behavior

Slow-moving and wary, it picks at small benthic invertebrates and algae near the substrate. When threatened it relies on armor and may emit a toxin; it is not a strong or fast swimmer.

Caution

Handle with care: cowfish can release ostracitoxin when stressed or injured, which can be dangerous to other fish in confined water. Do not place in livewells or aquariums with other fish; avoid eating unless locally verified as safe.

Fishing notes

Use ultra-light gear and small hooks if you are intentionally photographing or studying one, but avoid prolonged handling. In reef areas, expect incidental capture on small bait rigs near the bottom.