Naked Puffer, Sphoeroides lispus

Naked Puffer, Sphoeroides lispus. Fish caught from coastal waters off Puerto Peñasco, Sonora, November 2021. Length: 12 cm (4.7 inches). Catch, photograph and identification courtesy of Chris Moore, Peoria, Arizona.

Naked Puffer, Sphoeroides lispus. Fish caught from coastal waters off Puerto Peñasco, Sonora, November 2021. Length: 14 cm (5.5 inches). Catch, photograph and identification courtesy of Luke Ovgard, Klamath Falls, Oregon.

Naked Puffer, Sphoeroides lispus. Fish provided by the commercial fishermen of Bahía Kino, Sonora, March 2015. Length: 15.2 cm (6.0 inches). Photograph courtesy of Maria Johnson, Prescott College Kino Bay Center, Kino Bay, Sonora.

Naked Puffer, Sphoeroides lispus. Fish caught from coastal waters off Cabo San Lucas, Baja California Sur, December 2013. Length: 20 cm (7.9 inches). Catch, photograph and identification courtesy of Eli (obsessiveangling.wordpress.com).

The Naked Puffer, Sphoeroides lispus, is a member of the Puffer or Tetraodontidae Family, and is known in Mexico as botete liso or simply botete. Globally, there are twenty-three species in the genus Sphoeroides, of which thirteen are found in Mexican waters, eight in the Atlantic and five in the Pacific Ocean.

The Naked Puffer has a moderately elongated oblong body that are inflatable. They are light brown to gray in color transitioning to off-white ventrally. The iris of their eyes is orange. They have 1 prominent bar between the eyes on their back and 3 indistinct bars behind their pectoral fins, under their dorsal fin, and on their tail base. Their body is covered with small white dots and streaks and their caudal fin has a very dark outer half with a white margin. Their head is relatively long and slender with a wide flat section between the eyes. Their eyes are set high on the sides of the head. They have strong beaks composed of four fused teeth. Their short-based anal fin has 7 or 8 rays and is slightly behind the similarly-shaped dorsal fin, which also has 7 or 8 rays, toward the rear of the body; their caudal fin has a straight or convex margin; and, they do not have pelvic fins. They do not have fin spines, scales, skin spines, or fleshy skin flaps.

The Naked Puffer is a bottom dweller found in sandy and weedy areas at depths up to 34  m (110 feet). They reach a maximum of 35 cm (14 inches) in length. They are exceedingly well camouflaged and have the ability to blow themselves up like balloons, presumably as a defense mechanism to deter predator attacks. The Naked Puffer is a rare 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. They were only introduced to science in 1996.

The Naked Puffer is a resident of Mexican waters of the Pacific Ocean but has a limited distribution being found the Pacific being found form Guerrero Negro, Baja California, southward along the central and southwest coast of Baja, along the entire east coast of Baja, and along the west coast of the mainland in the northern half of the Sea of Cortez.

The Naked Puffer is a fairly easy fish to identify due to its coloration and markings but is very similar to the Longnose Puffer, Sphoeroides lobatus (ventral row of black spots).

From a conservation perspective the Naked Puffer is currently considered to be of Least Concern with stable, widely distributed populations. They are caught infrequently and primarily by deep-water trawlers. Note: Like many Puffers, the Naked Puffer is reputed to be highly poisonous, even fatal, if eaten, due to the possible presence of the potent neurotoxins saxitoxin and/or tetrodotoxin, which is found in their skin, viscera, and gonads and is believed to protect them from predation by larger fish.