Wrasse
Encyclopedia
The wrasses are a family
, Labridae, of marine fish
, many of which are brightly colored. The family is large and diverse, with over 600 species in 82 genera, which are divided into nine subgroups or tribes.
They are typically small fish, most of them less than 20 centimetres (7.9 in) long, although the largest, the Humphead wrasse
, can measure up to 2.5 metres (8.2 ft). They are efficient carnivores, feeding on a wide range of small invertebrates. Many smaller wrasses follow the feeding trails of larger fish, picking up invertebrates disturbed by their passing.
The word "wrasse" comes via Cornish
from the Welsh
word gwrach meaning an old woman or hag.
s and rocky shores where they live close to the substrate.
Wrasses have protractile mouths, usually with separate jaw teeth that jut outwards. Many species can be readily recognized by their thick lips, the inside of which is sometimes curiously folded, a peculiarity which gave rise the German name of "lip-fishes" (Lippfische.) The dorsal fin
has 8–21 spines and 6–21 soft rays, usually running most of the length of the back. Wrasse are sexually dimorphic. Many species are capable of changing sex. Juveniles are a mix of males and females (known as Initial Phase or IP individuals) but the largest adults become territory-holding (Terminal Phase or TP) males.
The wrasses have become a primary study species in fish-feeding biomechanics
due to their jaw structure. The nasal and mandibular
bones are connected at their posterior ends to the rigid neurocranium, and the superior and inferior articulations of the maxilla
are joined to the anterior tips of these two bones, respectively, creating a loop of 4 rigid bones connected by moving joints. This "four-bar linkage" has the property of allowing numerous arrangements to achieve a given mechanical result (fast jaw protrusion or a forceful bite), thus decoupling morphology from function. The actual morphology of wrasses reflects this, with many lineages displaying different jaw morphology that results in the same functional output in a similar or identical ecological niche.
hermaphrodite
s within a haremic
mating system
.
Hermaphroditism allows for complex mating systems. Labroids exhibit three different mating systems: polygynous, lek-like, and promiscuous
mating systems. Group spawning and pair spawning occur within mating systems. The type of spawning that occurs depends on male body size. Labroids typically exhibit broadcast spawning, releasing high amounts of plankton
ic eggs, which are broadcast by tidal
currents; adult labroids have no interaction with offspring. Wrasse of a particular subgroup of the Labridae family Labrini do not exhibit broadcast spawning.
, Centrolabrus, and Labrus
genera exhibit broodcare behavior.
Some wrasses are the known as Cleaner wrasse, the best-known of the cleaner fish
. They are symbiotic
, or more specifically, mutualistic fish, performing grooming functions for other species of fish, and benefiting themselves by feeding on what they remove. In this behaviour they are reminiscent of the Egyptian plover
, which is said to remove parasites from crocodiles.
The "client" fishes will congregate at wrasse cleaning station
s and wait for wrasses to swim into their open mouths and gill cavities to remove gnathiid
parasites.
Cleaner wrasses are best known for feeding on dead tissue and scales and ectoparasites, although they are also known to 'cheat
', consuming healthy tissue and mucus, which is energetically costly for the client fish to produce. The bluestreak cleaner wrasse
, Labroides dimidiatus is one of the commonest cleaners found on tropical reefs. Few cleaner wrasses have been observed being eaten by predators, possibly because parasite removal is more important for predator survival than the short-term gain of eating the cleaner.
Other wrasse species, rather than inhabiting fixed locations, make "house calls" — that is, their "clientele" are too territorial or shy to go to a cleaning station.
.
Wrasse are common in both public and home aquaria
. Some species are small enough to be considered reef safe
.
Wrasse may be employed as cleaner fish to combat sea-lice infestation in salmon farms
.
Labrines
Cheilines
Scarines
Pseudocheilines
Novaculines
Pseudolabrines
Labrichthyines
Julidines
Achoerodus
Ammolabrus
Anampses
Anchichoerops
Austrolabrus
Bodianus
Centrolabrus
Cheilinus
Cheilio
Choerodon
Cirrhilabrus
Clepticus
Conniella
Coris
Ctenolabrus
Cymolutes
Decodon
Diproctacanthus
Doratonotus
Dotalabrus
Epibulus
Eupetrichthys
Frontilabrus
Gomphosus
Halichoeres
Hemigymnus
Hologymnosus
Iniistius
Julichthys
Labrichthys
Labroides
Labropsis
Labrus
Lachnolaimus
Lappanella
Larabicus
Leptojulis
Macropharyngodon
Malapterus
Minilabrus
Nelabrichthys
Notolabrus
Novaculichthys
Novaculoides
Ophthalmolepis
Oxycheilinus
Oxyjulis
Paracheilinus
Parajulis
Pictilabrus
Polylepion
Pseudocheilinops
Pseudocheilinus
Pseudocoris
Pseudodax
Pseudojuloides
Pseudolabrus
Pteragogus
Semicossyphus
Stethojulis
Suezichthys
Symphodus
Tautoga
Tautogolabrus
Terelabrus
Thalassoma
Wetmorella
Xenojulis
Xiphocheilus
Xyrichtys
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
, Labridae, of marine fish
Fish
Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...
, many of which are brightly colored. The family is large and diverse, with over 600 species in 82 genera, which are divided into nine subgroups or tribes.
They are typically small fish, most of them less than 20 centimetres (7.9 in) long, although the largest, the Humphead wrasse
Humphead wrasse
The humphead wrasse is a wrasse that is mainly found in coral reefs in the Indo-Pacific region. It is also known as the Māori wrasse, Napoleon wrasse, Napoleonfish; or "So Mei" 蘇眉 and "Mameng" ....
, can measure up to 2.5 metres (8.2 ft). They are efficient carnivores, feeding on a wide range of small invertebrates. Many smaller wrasses follow the feeding trails of larger fish, picking up invertebrates disturbed by their passing.
The word "wrasse" comes via Cornish
Cornish language
Cornish is a Brythonic Celtic language and a recognised minority language of the United Kingdom. Along with Welsh and Breton, it is directly descended from the ancient British language spoken throughout much of Britain before the English language came to dominate...
from the Welsh
Welsh language
Welsh is a member of the Brythonic branch of the Celtic languages spoken natively in Wales, by some along the Welsh border in England, and in Y Wladfa...
word gwrach meaning an old woman or hag.
Distribution
Wrasses inhabit the Atlantic, Indian, and Pacific Oceans, usually in shallow water habitats such as coral reefCoral reef
Coral reefs are underwater structures made from calcium carbonate secreted by corals. Coral reefs are colonies of tiny living animals found in marine waters that contain few nutrients. Most coral reefs are built from stony corals, which in turn consist of polyps that cluster in groups. The polyps...
s and rocky shores where they live close to the substrate.
Anatomy
Dorsal fin
A dorsal fin is a fin located on the backs of various unrelated marine and freshwater vertebrates, including most fishes, marine mammals , and the ichthyosaurs...
has 8–21 spines and 6–21 soft rays, usually running most of the length of the back. Wrasse are sexually dimorphic. Many species are capable of changing sex. Juveniles are a mix of males and females (known as Initial Phase or IP individuals) but the largest adults become territory-holding (Terminal Phase or TP) males.
The wrasses have become a primary study species in fish-feeding biomechanics
Biomechanics
Biomechanics is the application of mechanical principles to biological systems, such as humans, animals, plants, organs, and cells. Perhaps one of the best definitions was provided by Herbert Hatze in 1974: "Biomechanics is the study of the structure and function of biological systems by means of...
due to their jaw structure. The nasal and mandibular
Mandibular
Mandibular may refer to:* Mandible, the lower jaw bone* Mandibular canal* Mandibular nerve...
bones are connected at their posterior ends to the rigid neurocranium, and the superior and inferior articulations of the maxilla
Maxilla
The maxilla is a fusion of two bones along the palatal fissure that form the upper jaw. This is similar to the mandible , which is also a fusion of two halves at the mental symphysis. Sometimes The maxilla (plural: maxillae) is a fusion of two bones along the palatal fissure that form the upper...
are joined to the anterior tips of these two bones, respectively, creating a loop of 4 rigid bones connected by moving joints. This "four-bar linkage" has the property of allowing numerous arrangements to achieve a given mechanical result (fast jaw protrusion or a forceful bite), thus decoupling morphology from function. The actual morphology of wrasses reflects this, with many lineages displaying different jaw morphology that results in the same functional output in a similar or identical ecological niche.
Reproductive Behavior
Most labroids are protogynousDichogamy
Sequential hermaphroditism is a type of hermaphroditism that occurs in many fish, gastropods and plants. Here, the individual is born one sex and changes sex at some point in their life. They can change from a male to female , or from female to male...
hermaphrodite
Hermaphrodite
In biology, a hermaphrodite is an organism that has reproductive organs normally associated with both male and female sexes.Many taxonomic groups of animals do not have separate sexes. In these groups, hermaphroditism is a normal condition, enabling a form of sexual reproduction in which both...
s within a haremic
Harem (zoology)
The term harem is used in zoology to describe the social organization of certain herbivore species, such as those in the Hominidae and Equidae families, into groups of females and young surrounding a single dominant male...
mating system
Mating system
A mating system is a way in which a group is structured in relation to sexual behaviour. The precise meaning depends upon the context. With respect to higher animals, it specifies which males mate with which females, under which circumstances; recognised animal mating systems include monogamy,...
.
Hermaphroditism allows for complex mating systems. Labroids exhibit three different mating systems: polygynous, lek-like, and promiscuous
Promiscuity
In humans, promiscuity refers to less discriminating casual sex with many sexual partners. The term carries a moral or religious judgement and is viewed in the context of the mainstream social ideal for sexual activity to take place within exclusive committed relationships...
mating systems. Group spawning and pair spawning occur within mating systems. The type of spawning that occurs depends on male body size. Labroids typically exhibit broadcast spawning, releasing high amounts of plankton
Plankton
Plankton are any drifting organisms that inhabit the pelagic zone of oceans, seas, or bodies of fresh water. That is, plankton are defined by their ecological niche rather than phylogenetic or taxonomic classification...
ic eggs, which are broadcast by tidal
Tide
Tides are the rise and fall of sea levels caused by the combined effects of the gravitational forces exerted by the moon and the sun and the rotation of the Earth....
currents; adult labroids have no interaction with offspring. Wrasse of a particular subgroup of the Labridae family Labrini do not exhibit broadcast spawning.
Broodcare Behavior of Labrine Tribe
The subgroup Labrini arose from a basal split within family Labridae during the Eocene period. Subgroup Labrini is composed of eight genera, wherein 15 out of 23 species exhibit broodcare behavior. Broodcare behavior ranges from simple to complex parental care of spawn; males build algae nests or crude cavities, ventilate eggs, and defend nests against conspecific males and predators. In species that express this behavior, eggs cannot survive without parental care. Species of SymphodusSymphodus
Symphodus is a genus of fish of Labridae family.- Species :*Symphodus bailloni - Baillon's wrasse*Symphodus cinereus - Grey wrasse*Symphodus doderleini Jordan, 1890...
, Centrolabrus, and Labrus
Labrus
Labrus is a genus of wrasses of the Labridae family, currently with four recognised species*Ballan wrasse, Labrus bergylta Ascanius, 1767 *Brown wrasse, Labrus merula Linnaeus, 1758 *Cuckoo wrasse, Labrus mixtus Linnaeus, 1758...
genera exhibit broodcare behavior.
Cleaner wrasse
Cleaner fish
Cleaner fish are fish that provide a service to other fish species by removing dead skin and ectoparasites. This is an example of mutualism, an ecological interaction that benefits both parties involved. A wide variety of fishes have been observed to display cleaning behaviors including wrasses,...
. They are symbiotic
Symbiosis
Symbiosis is close and often long-term interaction between different biological species. In 1877 Bennett used the word symbiosis to describe the mutualistic relationship in lichens...
, or more specifically, mutualistic fish, performing grooming functions for other species of fish, and benefiting themselves by feeding on what they remove. In this behaviour they are reminiscent of the Egyptian plover
Egyptian Plover
The Egyptian Plover is a wader, the only member of the genus Pluvianus. Formerly placed in the pratincole and courser family, Glareolidae, it is now regarded as the sole member of its own monotypic family Pluvianidae....
, which is said to remove parasites from crocodiles.
The "client" fishes will congregate at wrasse cleaning station
Cleaning station
A cleaning station is a location where fish, sea turtles, hippo and other aquatic life, freshwater and marine, congregate to be cleaned.The cleaning process includes the removal of parasites from the animal's body , and can be performed by various creatures A cleaning station is a location where...
s and wait for wrasses to swim into their open mouths and gill cavities to remove gnathiid
Gnathiidae
Gnathiidae is a family of isopod crustaceans. They occur in a wide range of depths, from the littoral zone to the deep sea. The adults are associated with sponges and may not feed...
parasites.
Cleaner wrasses are best known for feeding on dead tissue and scales and ectoparasites, although they are also known to 'cheat
Cheating (biology)
Cheating is a metaphor commonly used in behavioral ecology to describe organisms that receive a benefit at the cost of others. Cheating is common in many mutualistic and altruistic relationships. Natural selection favors cheating, but there are mechanisms to regulate cheating.- Theoretical Models...
', consuming healthy tissue and mucus, which is energetically costly for the client fish to produce. The bluestreak cleaner wrasse
Bluestreak cleaner wrasse
The bluestreak cleaner wrasse is one of several species of cleaner wrasse found on coral reefs in the Indian Ocean and much of the Pacific Ocean, as well as many seas, including the Red Sea and those around Southeast Asia...
, Labroides dimidiatus is one of the commonest cleaners found on tropical reefs. Few cleaner wrasses have been observed being eaten by predators, possibly because parasite removal is more important for predator survival than the short-term gain of eating the cleaner.
Other wrasse species, rather than inhabiting fixed locations, make "house calls" — that is, their "clientele" are too territorial or shy to go to a cleaning station.
Significance to humans
Humans eat wrasse in many places. In the western Atlantic, the most common food species is the tautogTautog
The tautog or blackfish also known as the "poor-man's lobster" , Tautoga onitis, is a fish of the wrasse family found in salt water from Nova Scotia to Georgia...
.
Wrasse are common in both public and home aquaria
Aquarium
An aquarium is a vivarium consisting of at least one transparent side in which water-dwelling plants or animals are kept. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, marine mammals, turtles, and aquatic plants...
. Some species are small enough to be considered reef safe
Reef safe
Reef safe is a distinction used in the saltwater aquarium hobby to indicate that a fish or invertebrate is safe to add to a reef aquarium. There is no fish that is completely reef safe. Every fish that is commonly listed as reef safe are species that usually do not readily consume small fish or...
.
Wrasse may be employed as cleaner fish to combat sea-lice infestation in salmon farms
Aquaculture of salmon
Salmon, along with carp, are the two most important fish groups in aquaculture. In 2007, the aquaculture of salmon and salmon trout was worth US$10.7 billion. The most commonly farmed salmon is the Atlantic salmon. Other commonly farmed fish groups include tilapia, catfish, sea bass, bream and...
.
Subgroups/Tribes
HypsigenyinesLabrines
Cheilines
Scarines
Pseudocheilines
Novaculines
Pseudolabrines
Labrichthyines
Julidines
Genera
AcantholabrusAcantholabrus
Acantholabrus is a genus of wrasse in the Labridae family. It contains one species, Acantholabrus palloni....
Achoerodus
Achoerodus
Achoerodus is a genus of wrasse in the Labridae family.-Species:* Achoerodus gouldii – Western Blue Groper * Achoerodus viridis – Eastern Blue Groper...
Ammolabrus
Anampses
Anampses
Anampses is a genus of wrasses in the family Labridae.- Species :* Bluespotted wrasse, Anampses caeruleopunctatus Rüppell, 1829* Red tail wrasse, Anampses chrysocephalus Randall, 1958* Pearl wrasse, Anampses cuvier Quoy & Gaimard, 1824...
Anchichoerops
Austrolabrus
Bodianus
Bodianus
Bodianus is a genus of wrasses in the family Labridae.- Species :* Lyretail hogfish, Bodianus anthioides * Axilspot hogfish, Bodianus axillaris * Bodianus bathycapros Gomon, 2006...
Centrolabrus
Cheilinus
Cheilinus
Cheilinus is a genus of wrasses in the family Labridae.- Species list :* Cheilinus abudjubbe Rüppell, 1835* Speckled maori wrasse, Cheilinus arenatus Valenciennes, 1840* Cheilinus aurantiacus Castelnau, 1872...
Cheilio
Choerodon
Choerodon
Choerodon is a genus of wrasses in the family Labridae.- Species :* Orange-dotted tuskfish, Choerodon anchorago * Choerodon azurio * Choerodon balerensis Herre, 1950...
Cirrhilabrus
Cirrhilabrus
Cirrhilabrus is a genus of wrasses in the family Labridae, commonly known as fairy wrasse. Popular among aquaria hobbyists, the fish are generally considered reef safe and often brightly colored.- History :...
Clepticus
Conniella
Coris
Ctenolabrus
Cymolutes
Decodon
Diproctacanthus
Doratonotus
Dotalabrus
Epibulus
Eupetrichthys
Frontilabrus
Gomphosus
Halichoeres
Halichoeres
The wrasse genus Halichoeres includes among others the ray-finned fish collectively called yellow wrasses.Fishbase lists 75 species:*Halichoeres adustus , Black wrasse...
Hemigymnus
Hologymnosus
Iniistius
Julichthys
Labrichthys
Labroides
Labropsis
Labrus
Labrus
Labrus is a genus of wrasses of the Labridae family, currently with four recognised species*Ballan wrasse, Labrus bergylta Ascanius, 1767 *Brown wrasse, Labrus merula Linnaeus, 1758 *Cuckoo wrasse, Labrus mixtus Linnaeus, 1758...
Lachnolaimus
Lappanella
Larabicus
Leptojulis
Macropharyngodon
Malapterus
Minilabrus
Nelabrichthys
Notolabrus
Notolabrus
Notolabrus is a genus of wrasses in the family Labridae.- Species :* Spotty, Notolabrus celidotus * Girdled wrasse, Notolabrus cinctus...
Novaculichthys
Novaculoides
Ophthalmolepis
Oxycheilinus
Oxyjulis
Paracheilinus
Paracheilinus
Paracheilinus is a genus of fish in the family Labridae.-Species:*Paracheilinus angulatus Randall & Lubbock, 1981.*Paracheilinus attenuatus Randall, 1999.*Paracheilinus bellae Randall, 1988....
Parajulis
Pictilabrus
Polylepion
Pseudocheilinops
Pseudocheilinus
Pseudocheilinus
Pseudocheilinus is a genus of fish in the family Labridae, or the wrasses. They are a marine, ray-finned fish. Pseudocheilinus is one of the smaller genera of wrasse.-Species:*Pseudocheilinus citrinus Randall, 1999....
Pseudocoris
Pseudodax
Pseudojuloides
Pseudojuloides
Pseudojuloides is a genus of wrasse in the family Labridae.- Species :* Genus Pseudojuloides** Pseudojuloides argyreogaster ** Polynesian wrasse, Pseudojuloides atavai Randall & Randall, 1981...
Pseudolabrus
Pseudolabrus
Pseudolabrus is a genus of wrasses in the family Labridae.- Species :* Genus Pseudolabrus** Pseudolabrus biserialis ** Red naped wrasse, Pseudolabrus eoethinus ** Pseudolabrus fuentesi...
Pteragogus
Semicossyphus
Semicossyphus
Semicossyphus is a genus of fish in the Labridae family.It contains the following species:* Asian sheepshead wrasse * California sheephead...
Stethojulis
Suezichthys
Suezichthys
Suezichthys is a genus of wrasses in the family Labridae.- Species :* Genus Suezichthys** Rainbow slender wrasse, Suezichthys arquatus Russell, 1985** Crimson cleaner fish, Suezichthys aylingi Russell, 1985...
Symphodus
Symphodus
Symphodus is a genus of fish of Labridae family.- Species :*Symphodus bailloni - Baillon's wrasse*Symphodus cinereus - Grey wrasse*Symphodus doderleini Jordan, 1890...
Tautoga
Tautogolabrus
Terelabrus
Thalassoma
Thalassoma
Thalassoma is a genus of wrasses in the family Labridae.- Species :* Thalassoma amblycephalum – Bluntheaded Wrasse * Thalassoma ascensionis – Greenfish...
Wetmorella
Xenojulis
Xiphocheilus
Xyrichtys
Xyrichtys
Xyrichtys is a genus of wrasses found in sandy-bottomed ocean habitats throughout the world. They are commonly known as razorfishes as they are very laterally compressed with a sharp bony ridge at the front of the head...