Bluestreak Cleaner Wrasse

About

The bluestreak cleaner wrasse (Labroides dimidiatus) is one of the most ecologically important fish on any coral reef, and one of the most challenging to keep well in captivity. Found across an enormous range stretching from the Red Sea and East Africa all the way to the central Pacific, this species sets up dedicated cleaning stations on the reef where other fish, sometimes lining up in numbers, wait to have parasites, dead tissue, and mucus removed from their bodies, gills, and even mouths. That relationship is not incidental; it is the core of how this fish lives. In the wild, a cleaning station may be occupied by a bonded pair of adults, a group of juveniles, or a group of females with a dominant male. This species is a protogynous hermaphrodite, meaning a female will transition to a functional male if the dominant male of a group disappears. The signature behavior is a distinctive swaying, undulating dance used to advertise cleaning services to passing fish. Juveniles will often perform the same movement when a diver approaches closely. The fish itself is slender and pale with a bold dark horizontal stripe running from nose to tail. In the aquarium, meeting its dietary needs long-term is genuinely difficult, and it is best considered a species for experienced marine keepers with well-established reef systems.