Blue streak wrasses are brilliant blue with a broad jet-black band that runs from the tip of the snout to the end of the tail, starting out narrow at the anterior end and gradually broadening towards the posterior end. Their diet consists primarily of parasitic copepods and other invertebrates that are taken from the mouth and gill openings of larger fish. They also feed occasionally on free-swimming crustaceans. Blue streak wrasses are known as common cleaner fish that set up cleaning stations on various parts of coral reefs, usually 3-10ft. deep. They attract larger fish to their stations by making strange, oscillatory swimming movements, and the fish then stop to get cleaned.
Wrasses enter the mouth and gill openings and remove any ectoparasites and diseased tissue.
The larger fish not only refrain from devouring these small cleaner fish, but actually readily open their mouth and gill cavities so that they are able to clean. Reproduction Wrasses practice external fertilization in which the female's eggs are released into the water. Large males defend reef territories and attract multiple females to these territories, usually by performing a beautiful mating dance. Females live within these territories and spawn with the male. If the territorial male leaves or dies, the most dominant female will take his role and become male within the next 24 hours.