Distribution:
Puffers are found in tropical and subtropical areas of all oceans of the world and a few species occur in freshwater.
Habitat:
Puffers occupy a wide variety of habitats ranging from coastal reefs and lagoons, estuaries, freshwaters and even the open ocean in the epipelagic zone.
Remarks:
Puffers typically have a small mouth and strong beak-like jaws divided into two upper and two lower teeth, the source of the scientific name of the family (tetra = four + odont = tooth). Puffers also have small gill slits located just in front of the pectoral fins. They lack fin spines, and the small dorsal and anal fins are located far back on the body which is either naked or covered with small prickles.
The common name of “puffer” is derived from the ability of these fishes to inflate their body when alarmed or threatened by swallowing water into their expandable stomachs (a behavior shared with the spiny boxfishes, Diodontidae). Puffers swim by rapidly beating their pectoral fins, often aided by sculling movements of the dorsal and anal fins. Many species are toxic, harboring a powerful neurotoxin in their tissues, especially in the internal organs.
There are two subfamilies, the Tetraodontinae, with about 100 species that include the world famous fugu, and the Canthigasterinae or sharpnose puffers that include a single genus and 26 species.
Reference:
Wheeler 1975;
Nelson 2006