Porcupinefishes also known as burrfishes or spiny puffers belong to the family „Diodontidae“. No other family has the following combination of characters: large spines on body; no pelvic fins; inflatable body; and teeth fused into a single beak-like unit in each jaw, without median suture dividing upper and lower jaws into right and left halves. 19 species of Porcupinefishes commonly found in tropical oceans all over the world near tropical reefs.
They range from 30 to 90 cm long. When threatened, the fish may swallow water or air and inflate its body into a ball. Their skin is usually spotted. The upper and lower teeth are each fused, producing a beaklike mouth. Pufferfishes eat crustaceans and mollusks like smelt, squid and krill. They use their teeth to scrape and crush the shells of crustaceans.
The porcupine fish is related to the puffer fish (Family Tetraodontidae). Adults live close to the shore and by reefs. They can be found hiding under small cliffs. The young porcupinefishes live in the open ocean. Porcupinefishes cannot swim very fast, but if an enemy get too close the it puffs up. Sharks are the only real predators.