The Hawaiian cleaner wrasse or golden cleaner wrasse (''Labroides phthirophagus''), is a species of

wrasse The wrasses are a family, Labridae, of marine ray-finned fish, many of which are brightly colored. The family is large and diverse, with over 600 species in 81 genera, which are divided into nine subgroups or tribes. They are typically small, ...

(

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

Labroides ''Labroides'' is a genus of wrasses native to the Indian and Pacific Oceans. This genus is collectively known as cleaner wrasses, and its species are cleaner fish Cleaner fish are fish that show a specialist feeding strategy by providing a ...

'') found in the waters surrounding the

Hawaiian Islands The Hawaiian Islands () are an archipelago of eight major volcanic islands, several atolls, and numerous smaller islets in the Pacific Ocean, North Pacific Ocean, extending some from the Hawaii (island), island of Hawaii in the south to nort ...

. The fish is

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to Hawaii. These

cleaner fish Cleaner fish are fish that show a specialist feeding strategy by providing a service to other species, referred to as clients, by removing dead skin, ectoparasites, and infected tissue from the surface or gill chambers. This example of cleaning ...

inhabit coral reefs, setting up a territory referred to as a

cleaning station A cleaning station is a location where aquatic life congregate to be cleaned by smaller beings. Such stations exist in both freshwater and marine environments, and are used by animals including fish, sea turtles and hippos. The cleaning process ...

. They obtain a diet of small crustacean parasites by removing them from other reef fish in a

cleaning symbiosis Cleaning is the process of removing unwanted substances, such as dirt, infectious agents, and other impurities, from an object or environment. Cleaning is often performed for beauty, aesthetic, hygiene, hygienic, Function (engineering), function ...

Description

The Hawaiian cleaner wrasse grows to a maximum length of about . This fish is strikingly coloured; the anterior part is golden, with a dark lateral stripe running from the eye to the tail, becoming wider at the back. The posterior part of the fish has purple and violet colouration on the fins.

Distribution and habitat

This fish is

to the Hawaiian Islands and nearby

Johnston Atoll Johnston Atoll is an Unincorporated territories of the United States, unincorporated territory of the United States, under the jurisdiction of the United States Air Force (USAF). The island is closed to public entry, and limited access for mana ...

. It is typically found on coral and rocky reefs, but avoids the surge zone. It is found at depths down to about .

Ecology

The Hawaiian cleaner wrasse moves with a graceful flitting movement. At night it may rest in a balloon-like cocoon it builds from mucus. The species is

monogamous Monogamy ( ) is a relationship of two individuals in which they form a mutual and exclusive intimate partnership. Having only one partner at any one time, whether for life or serial monogamy, contrasts with various forms of non-monogamy (e.g. ...

, with a pair bond being formed during the breeding season. It is an obligate feeder on the

ectoparasite Parasitism is a Symbiosis, close relationship between species, where one organism, the parasite, lives (at least some of the time) on or inside another organism, the Host (biology), host, causing it some harm, and is Adaptation, adapted str ...

s of other fish to the extent that it will fail to thrive in an aquarium where these feeding needs are not met. The behaviour of this fish is very similar to that of the closely related

bluestreak cleaner wrasse The bluestreak cleaner wrasse (''Labroides dimidiatus'') is one of several species of cleaner wrasses found on coral reefs from Eastern Africa and the Red Sea to French Polynesia. Like other cleaner wrasses, it eats parasites and dead tissue off ...

(''Labroides dimidiatus''), widely found in the rest of Indo-Pacific region. Both species operate

s where larger fish (clients) visit and cooperate in the removal by the cleaner fish of their ectoparasites, loose flakes of skin and mucus. The arrangement is mutually beneficial, with the client fish having its parasites removed and the wrasse gaining protection and finding an easy meal. The process is not without danger for the cleaner fish as many of the client fish are

piscivore A piscivore () is a carnivorous animal that primarily eats fish. Fish were the diet of early tetrapod evolution (via water-bound amphibians during the Devonian period); insectivory came next; then in time, the more terrestrially adapted repti ...

s, but observations in the wild show an apparent absence of "cheating" by the client fish, which seem to appreciate the tactile stimulation provided by the cleaner fish moving around their skin and fins. It seems that cleaner fish build up a relationship with their clients and there is some communication between them. When the client arrives at a cleaning station, it observes what the cleaner fish is doing, if it already has a client, of the cleaner's previous client "jolts" (twitches in response to a cleaner "cheating" by taking a bite of the client's scales or mucus), in which case the prospective client may depart. If happy with what it sees, the client adopts a certain species-specific pose which invites the cleaner fish to set to work on it.

Status

This fish has a restricted range in the vicinity of the Hawaiian Islands but is relatively common there. Much of its range is within the

Papahānaumokuākea Marine National Monument The Papahānaumokuākea Marine National Monument (PMNM) (roughly ) is a World Heritage Site, World Heritage listed National monument (United States), U.S. national monument encompassing of ocean waters, including ten islands and atolls of th ...

, a well-managed

marine protected area A marine protected area (MPA) is a protected area of the world's seas, oceans, estuaries or in the US, the Great Lakes. These marine areas can come in many forms ranging from wildlife refuges to research facilities. MPAs restrict human activity ...

. No specific threats to this fish have been identified although degradation of its coral reef habitat is likely to have some impact on it. The

International Union for Conservation of Nature The International Union for Conservation of Nature (IUCN) is an international organization working in the field of nature conservation and sustainable use of natural resources. Founded in 1948, IUCN has become the global authority on the stat ...

has assessed its conservation status as being of "

least concern A least-concern species is a species that has been evaluated and categorized by the International Union for Conservation of Nature (IUCN) as not being a focus of wildlife conservation because the specific species is still plentiful in the wil ...

Aquatic Trade

This fish is sometimes taken out of the wild for aquarium trade around the world. It can be found on many aquatic fish websites.

References

{{Taxonbar, from=Q2613431 Fish of Hawaii Hawaiian cleaner wrasse Fish described in 1958