Black-spot keeled pufferfish, Triodontidae
Triodon macropterus (common name the threetooth puffer and the black-spot keeled pufferfish) 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. The threetooth puffer was first scientifically described by René Lesson in 1831 and is recognizable for its large belly flap which has the ability to blend into the body when fully retracted.
The name Triodon macropterus comes from the Ancient Greek τρι- (tri-, meaning 'three') and ὀδούς (or ὀδών, odoús, odṓn, meaning 'tooth'), and refers to the three fused teeth that make up a beak-like structure.
The threetooth puffer is native to the Indo-Pacific, where it is found mainly around Australia and off the coast of Asia at depths from 30–300 m (98–984 ft). Its habitat is pelagic, consisting of continental shelves, slopes, seamounts, and knolls.
Little is known about the diet of the threetooth puffer. However, a dissection of the stomach of a caught juvenile specimen uncovered traces of mysid crustacean, foraminifera, echinoids, and sponges.
The intestinal tract of the threetooth puffer (the esophagus, stomach, and intestines) is lined with several papillae, protrusions of the gut lumen. After the stomach, the tract branches off into a specialized sac-like compartment called Tyler's Pouch. Within the Tyler's Pouch the papillae are much larger in size and number compared to those prior. The role and function of Tyler's Pouch is largely unknown.
Triodon macropterus is harmless to humans unless eaten, at which point the species is considered poisonous.
