Boxfish
box_fish
Thornback Cowfish
Lactoria fornasini
About
Shaped more like a box than a fish, the thornback cowfish grows up to 23 cm and gets around by slow, careful paddling rather than speed, relying on its armoured body for protection.
Also known as: thorny-back cow-fish, spiny-backed cow-fish, thorny-back cowfish, cofferfish
- Length
- 23 cm
- Depth
- 6–30 m
How to tell it apart
Other boxfish share the same fused, box-like shell shape. The single large spine rising from the middle of this species' back ridge is the mark that gives it away as the thornback cowfish rather than a spineless or smaller-spined relative.
Appearance
This fish's body is covered in fused, hexagon-shaped plates that form a solid, box-like shell, with only the eyes, mouth, fins and tail poking out. The shell gives it a purse-like outline: a fairly straight snout, a somewhat rounded back, flanks that curve inward, and a rounded belly. A large spine sticks up from the ridge along its back. Smaller spines sit in front of each eye, and another pair of spines project near the anal fin. The tail fin is fan-shaped. Colour varies and can shift to match the surroundings, usually pale tan marked with wiggly lines and spots in yellow, mauve or blue.
Habitat
It lives over sand, rubble, coral and algae, both in lagoons and on the seaward side of reefs. It is usually found from about 6 to 30 metres deep, though it has been recorded as deep as 132 metres. It is usually seen alone, and males defend a territory during the breeding season.
Did you know?
This species was first formally described in 1846 by the Italian zoologist Giovanni Giuseppe Bianconi, from a specimen collected in Mozambique.
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