Bluestreak Cleaner Wrasse (Labroides dimidiatus)
Observed: Koh Chang Reefs, 2015
Observed By: Hanah Weerkamp
The wrasse family are the carwashes of the ocean. These unique fishes subsist on the parasites and dead tissue that grow on other fish species. They establish cleaning stations where all kinds of fish swim up for a clean-up. This removes irritating and harmful parasites from the fish and provides a food source for the wrasse. Even sharks and other predatory species will call a truce with the wrasse in order for a much-needed cleanup.
Bluestreak cleaner wrasse Wikipedia