Diodon hystrix is a circumtropical fish. Bulky fish with yellow, brown to gray color and white belly,large eyes and big head. Its head, body and fins are covered in dozens of small black spots, and it has many movable spines spread across its body. It looks similar in appearance to D. holocanthus, but that lacks the black spots on the fins.
Listed as Least Concern on the ICUN Red list. The species is generally common in tropical waters and there are no known threats.
Circumtropical species. From the Eastern Pacific: California, USA to Chile, including the Galapagos Islands. Western Atlantic: Bermuda, Massachusetts (USA), and northern Gulf of Mexico to Brazil. Eastern Atlantic: 30°N to 23°S. Western Indian Ocean: Red Sea to Madagascar, Reunion and Mauritius. It has been reported from the Mediterranean, but these sightings are unconfirmed. Porcupinefish are commonly seen in caves and holes in shallow seaward reefs and lagoons, in a depth rang of 3-50 meters.
Juveniles to about 20 cm are pelagic, adults are benthic. Individuals can reach an age of 10 years!
Up to 69 cm, but usually smaller, around 5o cm.
Diodon hystrix feeds on small, hard-shelled invertebrates such as crabs, gastropods and sea urchins.
They are nocturnal, which explains why you find them around caves during the day.