Genus (Animalia): Odonus

The redtoothed triggerfish (Odonus niger) is a triggerfish of the tropical Indo-Pacific area, and the sole member of its genus. Some other common names include blue triggerfish, redfang triggerfish, redtoothed filefish, and Niger triggerfish.

Description

Redtoothed triggerfish are normally deep purple with bluish-green markings on their heads and glowing light blue margins on the tail lobes and fins. Just like other fish in the family Balistidae, the tail is lyre-shaped. The mouth of the triggerfish seems to be grinning and it maintains tiny red teeth that are needle sharp with two teeth in the upper jaw which can be seen when its mouth is closed. These triggerfish are one of the more peaceful triggers in the family but can become threatening with age and can perform a grunting-type sound. They have the ability to change their color depending on their mood, food, feeding and water quality from purple to blue and to bluish-green.

Their pectoral fins are quite small; as a result they steer mostly with their dorsal and anal fins, which makes them very maneuverable, and they also use these fins to move with an exotic type of propulsion reminiscent of a propeller. It is one of the most singular swimming styles in the ocean.

Reference: Wikipedia