Porcupinefish

Diodontidae

Round, spiny, and slightly goofy-looking, porcupinefish hover near overhangs and reef walls. When relaxed, their spines lie flat and they're surprisingly approachable. Never harass them into inflating — it's extremely stressful for the fish.

Last updated April 2026

Species

Porcupinefish

Diodon hystrix(4 photos)

Least ConcernUp to 90 cm3–50mCoral reefRocky reef

A round, spiky fish covered in long sharp spines — inflates into a ball when threatened. Brown with dark spots and large, expressive eyes.

Swims slowly along reef edges, often resting under table corals at night — avoid touching, as the spines can cause painful injuries.

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