Trigger fish

Triggerfishes (Balistidae)  have a first dorsal fin spine that can be locked into an erect position. This is made possible by a ball and socket "trigger-like" mechanism. The base of the second spine slots into a groove in the first spine.Triggerfishes are about 40 species of often brightly colored fish of the family Balistidae. Often marked by lines and spots.Most are found in relatively shallow.

Lagoon trigger fish

The Trigger Fish can be found in great numbers in the Indo-Pacific, especially at coastal areas or in coral reefs. This gorgeous fish features an oval-shaped body and a large head that includes a small but very powerful mouth that it uses to crush shells. Even though some fish are widely known to have a very short-term memory, the Trigger Fish is surprisingly intelligent and can even learn from past experiences. Its diet consists of mostly sea urchins, mollusks and crustaceans, but some species will also eat small fish, plankton or algae.

Clown Trigger fish