A heavy tan fish to 91 cm (3 ft), spotted black over the body and the fins, with big green-gold eyes and spines lying flat along the skin. At rest it looks like a lumpy pufferfish; the spines only become obvious when they stand up, and they only stand up when the fish inflates.
Inflation is a one-trick defense with real costs. Water is pumped into an elastic stomach chamber until the body is a rigid ball two or three times its normal diameter, locking the spines outward; the fish cannot swim while inflated, takes minutes to recover afterward, and is exhausted by it. It is a last resort rather than a display, and lifting one out of the water to make it puff for a photograph can kill it.
The jaw is the other half of the animal. Four teeth fused into a solid beak crush urchins, hermit crabs and molluscs, and the bite is strong enough to take a finger from a careless fisherman handling one.
Like other porcupinefishes it carries tetrodotoxin in the skin, liver and gonads, accumulated from bacteria in its food. Nothing eats an adult, and nothing should.
The genus. Diodon Linnaeus 1758 - di- (two) + odon (tooth). ETYFish
The species. Diodon hystrix Linnaeus 1758 - porcupine. ETYFish
- heavy tan body covered in small black spots, including on the fins
- long spines lying flat along the body until the fish inflates
- large protruding eyes with a green-gold iris, and a beak of fused teeth
- length up to 91 cm
