Porcupinefish, Diodon hystrix
The Porcupinefish, Diodon hystrix, whose common Spanish name is pez erizo pecoso, and known locally as botete, is a species in the Porcupinefish or Diodontidae Family, known collectively as pez erizo in Mexico. Globally, there are only seven species in the genus Diodon, four of which are found in Mexican waters, two in both the Atlantic and the Pacific, one in the Atlantic and one in the Pacific.
The Porcupinefish have robust inflatable bodies, which feature a wide blunt head, disproportionately large eyes, strong parrot-like teeth on both jaws, and a large mouth. Dorsally they are light gray brown in color with their shading changing to white ventrally. Their upper body, as well as their anal, caudal, and dorsal fins are covered with small black spots. Their body and head are covered with numerous, long, erectile, slender, and round spines; a row of 16 to 20 erectile spines runs from the top of their snout to their dorsal fins with the spines at the front of the head being shorter than the spines further back on the body. They also have one or two small spines on top of their caudal fin base.
The Porcupinefish are found in and around coral and rocky reefs at depths up to 445 feet; juveniles can be found in estuaries. They reach a maximum length of 91 cm (36 inches). Adults are generally found inshore and around areas that offer shelter such as caves, shipwrecks, reefs, and ledges. They are nocturnal and solitary creatures, commonly residing in holes and crevices within the reef complex. Juveniles are pelagic until reaching 20 cm (8 inches) in length, after which they become benthic. Their favorite food is live lightfoot sally crabs. They are preyed upon by large carnivorous fish including dorados, sharks, and wahoos. They are capable of expanding their body size by taking in water and inflating, which they use as an effective defense mechanism.
The Porcupinefish can be confused with the Balloonfish, Diodon holocanthus (smaller, narrower head with brown bars, fins without spots) and the Spotfin Burrfish, Chilomycterus reticulates (small number of short immovable spines, gray bars dorsally, white underbelly).
In Mexican waters the Porcupinefish are found in all waters of both the Atlantic and the Pacific with the exception that they are absent from the northern third of the Sea of Cortez.
The Porcupinefish is fairly common and readily accessible from the beach at certain times of the year in the greater Los Cabos area. Their favorite food is freshly collected live Lightfoot Sally Crabs. They should be considered to be a “catch and release” as they might contain the potent neurotoxin, tetrodotoxin and I strongly recommend that they not be used for human consumption. This species is also fairly common in public aquariums.
Porcupinefish, Diodon hystrix. Fish caught from shore at Km 21, Cabo Real, Baja California Sur, May 2003. Length 25 cm (10 inches). A fish with personality that will provide a unique photographic opportunity. Fish identification reconfirmed by H.J. Walker, Jr., Scripps Institution of Oceanography La Jolla, CA and Dr. Jeff Leis, Sydney, Australia.
Porcupinefish, Diodon hystrix. Set of embedded thorns removed from a 34 cm (13 inch) fish collected as a “floater” at sea off Point Palmilla, Baja California Sur, January 2015. Maximum spine length 2.7 cm (1.1 inches) and amazingly sharp.