Triodontidae

Threetooth puffer
Triodon macropterus, with extended belly flap
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Tetraodontiformes
Family:	Triodontidae Bleeker, 1865-69
Genus:	Triodon G. Cuvier, 1829
Species:	T. macropterus
Binomial name
Triodon macropterus Lesson, 1831

Triodon macropterus, also known as the threetooth puffer, is a tetraodontiform fish, the only living species in the genus Triodon and family Triodontidae. Other members of the family are known from fossils stretching back to the Eocene.

It is native to the Indo-Pacific, where found at depths to 300 m (980 ft). Its name comes from the Greek tria meaning "three" and odous meaning "tooth", and refers to the three fused teeth making up a beak-like structure.

The threetooth puffer reaches a maximum length of 54 cm (21 in). It has a distinctive shape, with a huge belly flap as large as or larger than its body; it inflates this with seawater when threatened. The flap bears an eye-spot, and is inflated by rotating the shaft-like pelvis downwards. This makes the animal appear much larger to predators, and less likely to be eaten.

The threetooth puffer is also known as the Black-spot keeled pufferfish, and was first scientifically described by Lesson in 1831.

Freshly caught specimen, belly flap half extended

Eye

Eye-looking lateral black spot

Teeth

Museum specimen

Drawing by Cuvier

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