Porcupinefish, Diodon hystrix
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, California and Dr. Jeff Leis, Sydney, Australia.
Porcupinefish, Diodon hystrix. Set of embedded thorns removed from a 34 cm (13 inches) 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.
Porcupinefish, Diodon hystrix. Underwater photographs taken in Zihuantanejo Bay, Guerrero, March 2018. Photographs courtesy of Ron Woheau, Zihuantanejo.
Porcupinefish, Diodon hystrix. Photograph and identification courtesy of Maude Jette, Dive Zihuantanejo, www.Divezihuatanejo.com, January 2019.
Porcupinefish, Diodon hystrix. Underwater photograph taken in coastal waters off Puerto Vallarta, Jalisco, July 2023. Photograph courtesy of Kevin Erwin, Seattle, Washington.
The Porcupinefish, Diodon hystrix, is a member of the Porcupinefish or Diodontidae Family, that is also known as the Spot-fin Porcupinefish and in Mexico as pez pecoso or simply botete. Globally, there are seven species in the genus Diodon, of which four are found in Mexican waters, one in the Atlantic, one in the Pacific and two in both the Atlantic and Pacific Oceans.
The Porcupinefish has a robust inflatable body with 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 1 or 2 small spines on top of their caudal fin base.
The Porcupinefish is found in and around coral and rocky reefs at depths up to 136 m (445 feet); juveniles can be found in estuaries. They reach a maximum of 91 cm (3 feet 0 inches) in length. As of January 1, 2024, the International Game Fish Association world record stood at 4.36 kg (9 lbs 5 oz) with the fish caught in coastal waters off the Cook Islands in November 2014. 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 Sally Lightfoot 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 is poorly studied with very limited information available about their lifestyle and behavioral patterns including specific details on age, growth, longevity, movement patterns, diet, habitat use, and reproduction.
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).
The Porcupinefish is a resident of all Mexican waters of both the Atlantic and the Pacific with the exception that they are absent from the northern third of the Sea of Cortez.
From a conservation perspective the Porcupinefish is currently considered to be of Least Concern with stable, widely distributed populations. They are fairly common and readily accessible from the beach at certain times of the year in the greater Los Cabos area. They should be considered to be a “catch and release” as they might contain the potent neurotoxin, tetrodotoxin and they not be used for human consumption. This species is also fairly common in public aquariums. They are also dried and sold a curios by certain cultures. In Southeast Asia they can be found for sale in the local fish markets.