Parrotfishes are a group of about 90 fish species regarded as a

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

(Scaridae), or a subfamily (Scarinae) of the

wrasse 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 81 genera, which are divided into 9 subgroups or tribes. They are typically small, most of them le ...

s. With about 95 species, this group's largest

species richness Species richness is the number of different species represented in an ecological community, landscape or region. Species richness is simply a count of species, and it does not take into account the abundances of the species or their relative a ...

is in the

Indo-Pacific The Indo-Pacific is a vast biogeographic region of Earth. In a narrow sense, sometimes known as the Indo-West Pacific or Indo-Pacific Asia, it comprises the tropical waters of the Indian Ocean, the western and central Pacific Ocean, and the ...

. They are found in

coral reef A coral reef is an underwater ecosystem characterized by reef-building corals. Reefs are formed of colonies of coral polyps held together by calcium carbonate. Most coral reefs are built from stony corals, whose polyps cluster in groups. Co ...

s, rocky coasts, and

seagrass Seagrasses are the only flowering plants which grow in marine environments. There are about 60 species of fully marine seagrasses which belong to four families (Posidoniaceae, Zosteraceae, Hydrocharitaceae and Cymodoceaceae), all in the orde ...

beds, and can play a significant role in

bioerosion Bioerosion describes the breakdown of hard ocean substrates – and less often terrestrial substrates – by living organisms. Marine bioerosion can be caused by mollusks, polychaete worms, phoronids, sponges, crustaceans, echinoids, and ...

Description

Parrotfish are named for their

dentition Dentition pertains to the development of teeth and their arrangement in the mouth. In particular, it is the characteristic arrangement, kind, and number of teeth in a given species at a given age. That is, the number, type, and morpho-physiolo ...

, which is distinct from other fish, including other

labrid 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 81 genera, which are divided into 9 subgroups or tribes. They are typically small, most of them le ...

s. Their numerous teeth are arranged in a tightly packed mosaic on the external surface of their jaw bones, forming a

parrot Parrots, also known as psittacines (), are birds of the roughly 398 species in 92 genera comprising the order Psittaciformes (), found mostly in tropical and subtropical regions. The order is subdivided into three superfamilies: the Psittacoid ...

-like beak with which they rasp

algae Algae (; singular alga ) is an informal term for a large and diverse group of photosynthetic eukaryotic organisms. It is a polyphyletic grouping that includes species from multiple distinct clades. Included organisms range from unicellular mic ...

from coral and other rocky substrates (which contributes to the process of

). Maximum sizes vary within the family, with the majority of species reaching in length. However, a few species reach lengths in excess of , and the green humphead parrotfish can reach up to . The smallest species is the bluelip parrotfish (''Cryptotomus roseus''), which has a maximum size of .

Mucus

Some parrotfish species, including the queen parrotfish (''Scarus vetula''), secrete a mucus cocoon, particularly at night.Cerny-Chipman, E.
Distribution of Ultraviolet-Absorbing Sunscreen Compounds Across the Body Surface of Two Species of Scaridae.

DigitalCollections@SIT
' 2007. Accessed 2009-06-21. Prior to going to sleep, some species extrude mucus from their mouths, forming a protective cocoon that envelops the fish, presumably hiding its scent from potential predators. This mucus envelope may also act as an early warning system, allowing the parrotfish to flee when it detects predators such as

moray eel Moray eels, or Muraenidae (), are a family of eels whose members are found worldwide. There are approximately 200 species in 15 genera which are almost exclusively marine, but several species are regularly seen in brackish water, and a few are f ...

s disturbing the membrane. The skin itself is covered in another mucous substance which may have antioxidant properties helpful in repairing bodily damage, or repelling parasites, in addition to providing protection from

UV light Ultraviolet (UV) is a form of electromagnetic radiation with wavelength from 10 nm (with a corresponding frequency around 30 PHz) to 400 nm (750 THz), shorter than that of visible light, but longer than X-rays. UV radiation i ...

Feeding

Most parrotfish species are

herbivore A herbivore is an animal anatomically and physiologically adapted to eating plant material, for example foliage or marine algae, for the main component of its diet. As a result of their plant diet, herbivorous animals typically have mouthpart ...

s, feeding mainly on

epilithic Lithophytes are plants that grow in or on rocks. They can be classified as either epilithic (or epipetric) or endolithic; epilithic lithophytes grow on the surfaces of rocks, while endolithic lithophytes grow in the crevices of rocks (and are also ...

algae.Bonaldo, R.M. & R.D. Rotjan (2018). The Good, the Bad, and the Ugly: Parrotfishes as Coral Predators. ''in'' Hoey, A.S. & R.M. Bonaldo, eds. Biology of Parrotfishes. CRC Press. A wide range of other small organisms are sometimes eaten, including invertebrates (

sessile Sessility, or sessile, may refer to: * Sessility (motility), organisms which are not able to move about * Sessility (botany), flowers or leaves that grow directly from the stem or peduncle of a plant * Sessility (medicine), tumors and polyps that ...

and

benthic The benthic zone is the ecological region at the lowest level of a body of water such as an ocean, lake, or stream, including the sediment surface and some sub-surface layers. The name comes from ancient Greek, βένθος (bénthos), meaning "t ...

species, as well as

zooplankton Zooplankton are the animal component of the planktonic community ("zoo" comes from the Greek word for ''animal''). Plankton are aquatic organisms that are unable to swim effectively against currents, and consequently drift or are carried along by ...

), bacteria and

detritus In biology, detritus () is dead particulate organic material, as distinguished from dissolved organic material. Detritus typically includes the bodies or fragments of bodies of dead organisms, and fecal material. Detritus typically hosts commun ...

. A few mostly larger species such as the green humphead parrotfish (''Bolbometopon muricatum'') feed extensively on living

coral Corals are marine invertebrates within the class Anthozoa of the phylum Cnidaria. They typically form compact colonies of many identical individual polyps. Coral species include the important reef builders that inhabit tropical oceans and sec ...

( polyps). None of these are exclusive

corallivore A corallivore is an animal that feeds on coral. Corallivores are an important group of reef organism because they can influence coral abundance, distribution, and community structure. Corallivores feed on coral using a variety of unique adaptati ...

s, but polyps can make up as much as half their diet or even more in the green humphead parrotfish. Overall it has been estimated that fewer than one percent of parrotfish bites involve live corals and all except the green humphead parrotfish prefer algae-covered surfaces over live corals. Nevertheless, when they do eat coral polyps, localized coral death can occur. Their feeding activity is important for the production and distribution of coral sands in the reef

biome A biome () is a biogeographical unit consisting of a biological community that has formed in response to the physical environment in which they are found and a shared regional climate. Biomes may span more than one continent. Biome is a broader ...

, and can prevent algal overgrowth of the reef structure. The teeth grow continuously, replacing material worn away by feeding. Whether they feed on coral, rock or seagrasses, the substrate is ground up between the

pharyngeal teeth Pharyngeal teeth are teeth in the pharyngeal arch of the throat of cyprinids, suckers, and a number of other fish species otherwise lacking teeth.lemon shark The lemon shark (''Negaprion brevirostris'') is a species of shark from the family Carcharhinidae and is classified as a Vulnerable species by the International Union for the Conservation of Nature. Lemon sharks can grow to in length. They are o ...

. On Caribbean coral reefs, parrotfish are important consumers of

sponge Sponges, the members of the phylum Porifera (; meaning 'pore bearer'), are a basal animal clade as a sister of the diploblasts. They are multicellular organisms that have bodies full of pores and channels allowing water to circulate through t ...

s. An indirect effect of parrotfish grazing on sponges is the protection of reef-building corals that would otherwise be overgrown by fast-growing sponge species. Analysis of parrotfish feeding biology describes three functional groups: excavators, scrapers and browsers. Excavators have larger, stronger jaws that can gouge the substrate, leaving visible scars on the surface. Scrapers have less powerful jaws that can but infrequently do leave visible scraping scars on the substrate. Some of these may also feed on sand instead of hard surfaces. Browsers mainly feed on seagrasses and their

epiphyte An epiphyte is an organism that grows on the surface of a plant and derives its moisture and nutrients from the air, rain, water (in marine environments) or from debris accumulating around it. The plants on which epiphytes grow are called phoroph ...

s. Mature excavating species include ''

Bolbometopon muricatum The green humphead parrotfish (''Bolbometopon muricatum'') is the largest species of parrotfish, growing to lengths of and weighing up to . It is found on reefs in the Indian and Pacific Oceans, from the Red Sea in the west to Samoa in the east ...

'', '' Cetoscarus'', '' Chlorurus'' and ''

Sparisoma viride The stoplight parrotfish (''Sparisoma viride'') is a species of marine ray-finned fish, a parrotfish from the Family (biology), family Scaridae, inhabiting coral reefs in Florida, Caribbean Sea, Gulf of Mexico, Bermuda and as far south as Brazil. ...

''. These excavating species all feed as scrapers in early juvenile stages, but '' Hipposcarus'' and '' Scarus'', which also feed as scrapers in early juvenile stages, retain the scraping feeding mode as adults. Browsing species are found in the genera '' Calotomus'', '' Cryptotomus'', '' Leptoscarus'', '' Nicholsina'' and ''Sparisoma''. Feeding modes reflect habitat preferences, with browsers chiefly living in grassy seabed, and excavators and scrapers on coral reefs. Recently, the microphage feeding hypothesis challenged the prevailing paradigm of parrotfish as algal consumers by proposing that:- “''most parrotfishes are microphages that target cyanobacteria and other protein-rich autotrophic microorganisms that live on (epilithic) or within (endolithic) calcareous substrata, are epiphytic on algae or seagrasses, or endosymbiotic within sessile invertebrates.”''

Life cycle

The development of parrotfishes is complex and accompanied by a series of changes in sex and colour (polychromatism). Most species are

sequential hermaphrodites Sequential hermaphroditism (called dichogamy in botany) is a type of hermaphroditism that occurs in many fish, gastropods, and plants. Sequential hermaphroditism occurs when the individual changes its sex at some point in its life. In particular, ...

, starting as females (known as the initial phase) and then changing to males (the terminal phase). In many species, for example the

stoplight parrotfish The stoplight parrotfish (''Sparisoma viride'') is a species of marine ray-finned fish, a parrotfish from the family Scaridae, inhabiting coral reefs in Florida, Caribbean Sea, Gulf of Mexico, Bermuda and as far south as Brazil. It mainly feeds ...

(''Sparisoma viride''), a number of individuals develop directly to males (i.e., they do not start as females). These directly developing males usually most resemble the initial phase, and often display a different mating strategy than the terminal phase males of the same species.Bester, C.
Stoplight parrotfish.
'' Florida Museum of Natural History, Ichthyology Department. Accessed 15-12-2009 A few species such as the Mediterranean parrotfish (''S. cretense'') are secondary

gonochorists In biology, gonochorism is a sexual system where there are only two sexes and each individual organism is either male or female. The term gonochorism is usually applied in animal species, the vast majority of which are gonochoric. Gonochorism c ...

. This means that some females do not change sex (they remain females throughout their lives), the ones that do change from female to male do it while still immature (reproductively functioning females do not change to males) and there are no males with female-like colors (the initial phase males in other parrotfish). The marbled parrotfish (''Leptoscarus vaigiensis'') is the only species of parrotfish known not to change sex. In most species, the initial phase is dull red, brown, or grey, while the terminal phase is vividly green or blue with bright pink, orange or yellow patches. In a smaller number of species the phases are similar, and in the Mediterranean parrotfish the adult female is brightly colored, while the adult male is gray. In most species, juveniles have a different color pattern from adults. Juveniles of some tropical species can alter their color temporarily to

mimic MIMIC, known in capitalized form only, is a former simulation computer language developed 1964 by H. E. Petersen, F. J. Sansom and L. M. Warshawsky of Systems Engineering Group within the Air Force Materiel Command at the Wright-Patterson AFB in ...

other species. Where the sexes and ages differ, the remarkably different phases often were first described as separate species. As a consequence early scientists recognized more than 350 parrotfish species, which is almost four times the actual number. Most tropical species form large schools when feeding and these are often grouped by size. Harems of several females presided over by a single male are normal in most species, with the males vigorously defending their position from any challenge. As pelagic spawners, parrotfish release many tiny, buoyant eggs into the water, which become part of the

plankton Plankton are the diverse collection of organisms found in Hydrosphere, water (or atmosphere, air) that are unable to propel themselves against a Ocean current, current (or wind). The individual organisms constituting plankton are called plankt ...

. The eggs float freely, settling into the coral until hatching. The sex change in parrotfishes is accompanied by changes in circulating steroids. Females have high levels of estradiol, moderate levels of T and undetectable levels of the major fish androgen 11-ketotestosterone. During the transition from initial to terminal coloration phases, concentrations of 11-ketotestosterone rise dramatically and estrogen levels decline. If a female is injected with 11-ketotestosterone, it will cause a precocious change in gonadal, gametic and behavioural sex. Image:Scarus psittacus femelle.jpg, Female '' Scarus psittacus'' (= initial phase) Image:Scarus psittacus mâle.jpg, Male '' Scarus psittacus'' (= terminal phase)

Economic importance

A commercial

fishery Fishery can mean either the enterprise of raising or harvesting fish and other aquatic life; or more commonly, the site where such enterprise takes place ( a.k.a. fishing ground). Commercial fisheries include wild fisheries and fish farms, both ...

exists for some of the larger species, particularly in the Indo-Pacific, but also for a few others like the Mediterranean parrotfish. Protecting parrotfishes is proposed as a way of saving Caribbean coral reefs from being overgrown with seaweed and sponges. Despite their striking colors, their feeding behavior renders them highly unsuitable for most marine aquaria. A new study has discovered that the parrotfish is extremely important for the health of the

Great Barrier Reef The Great Barrier Reef is the world's largest coral reef system composed of over 2,900 individual reefs and 900 islands stretching for over over an area of approximately . The reef is located in the Coral Sea, off the coast of Queensland, ...

; it is the only one of thousands of reef fish species that regularly performs the task of scraping and cleaning inshore coral reefs.

Taxonomy

Traditionally, the parrotfishes have been considered to be a

level

taxon In biology, a taxon (back-formation from ''taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular nam ...

, Scaridae. Although

phylogenetic In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups o ...

and evolutionary analyses of parrotfishes are ongoing, they are now accepted to be a

clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, ...

in the

tribe The term tribe is used in many different contexts to refer to a category of human social group. The predominant worldwide usage of the term in English language, English is in the discipline of anthropology. This definition is contested, in p ...

Cheilini, and are now commonly referred to as scarine labrids (subfamily Scarinae, family Labridae). Some authorities have preferred to maintain the parrotfishes as a family-level taxon,Randall, J. E. (2007). ''Reef and Shore Fishes of the Hawaiian Islands.'' resulting in Labridae not being

monophyletic In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic gro ...

(unless split into several families). Nonetheless, according to the

World Register of Marine Species The World Register of Marine Species (WoRMS) is a taxonomic database that aims to provide an authoritative and comprehensive list of names of marine organisms. Content The content of the registry is edited and maintained by scientific specialist ...

the group is divided into two subfamilies as follows : * sub-family Scarinae ** genus '' Bolbometopon'' Smith, 1956 (1 species) ** genus '' Cetoscarus'' Smith, 1956 (2 species) ** genus '' Chlorurus'' Swainson, 1839 (18 species) ** genus '' Hipposcarus'' Smith, 1956 (2 species) ** genus '' Scarus'' Forsskål, 1775 (53 species) * sub-family Sparisomatinae ** genus '' Calotomus'' Gilbert, 1890 (5 species) ** genus '' Cryptotomus'' Cope, 1870 (1 species) ** genus '' Leptoscarus'' Swainson, 1839 (1 species) ** genus '' Nicholsina'' Fowler, 1915 (3 species) ** genus '' Sparisoma'' Swainson, 1839 (15 species) More recent studies retain the Scaridae as a family but place it alongside the

s of the family Labridae and the weed whitings

Odacidae The Odacidae are a small family of ray-finned fishes formerly classified within the order Perciformes, commonly known as cales, and weed whitings. They are related to the much larger families of the wrasses and parrotfish. More recent workers ha ...

in the order

Labriformes Labriformes is an order of ray-finned fishes which includes the wrasse, cales and parrotfishes, within the clade Percomorpha. Some authors include the Labroformes as the clade Labroidei within the Perciformes while others include more familie ...

, part of the

Percomorpha Percomorpha () is a large clade of ray-finned fish that includes the tuna, seahorses, gobies, cichlids, flatfish, wrasse, perches, anglerfish, and pufferfish. Evolution Percomorpha are the most diverse group of teleost fish today. Teleosts, an ...

. They also do not support the division of the Scaridae into two subfamilies.

Gallery

Image:Scarus globiceps mâle.jpg, '' Scarus globiceps'' (male) File:Parrotfish turquoisse.jpg, '' Chlorurus microrhinos'' File:Bolbometopon muricatum.jpg, ''

'' File:Viridescent Parrotfish - Calotomus viridescens.jpg, '' Calotomus viridescens'' File:Cetoscarus ocellatus Great Barrier Reef.jpg, '' Cetoscarus ocellatus'' File:Chlorurus sordidus by Jaroslaw Barski.jpg, '' Chlorurus sordidus'' File:Hipposcarus longiceps.jpg, '' Hipposcarus longiceps'' File:Queen parrotfish Scarus vetula (2442375123).jpg, ''

Scarus vetula The queen parrotfish (''Scarus vetula'') is a species of marine ray-finned fish, a parrotfish, in the family Scaridae. It is found on reefs in the tropical West Atlantic Ocean and the Caribbean Sea. Other common names include blownose, blue chu ...

'' File:Stoplight-parrotfish.jpg, ''

Timeline of genera

ImageSize = width:1000px height:auto barincrement:15px PlotArea = left:10px bottom:50px top:10px right:10px Period = from:-65.5 till:10 TimeAxis = orientation:horizontal ScaleMajor = unit:year increment:5 start:-65.5 ScaleMinor = unit:year increment:1 start:-65.5 TimeAxis = orientation:hor AlignBars = justify Colors = #legends id:CAR value:claret id:ANK value:rgb(0.4,0.3,0.196) id:HER value:teal id:HAD value:green id:OMN value:blue id:black value:black id:white value:white id:cenozoic value:rgb(0.54,0.54,0.258) id:paleogene value:rgb(0.99,0.6,0.32) id:paleocene value:rgb(0.99,0.65,0.37) id:eocene value:rgb(0.99,0.71,0.42) id:oligocene value:rgb(0.99,0.75,0.48) id:neogene value:rgb(0.999999,0.9,0.1) id:miocene value:rgb(0.999999,0.999999,0) id:pliocene value:rgb(0.97,0.98,0.68) id:quaternary value:rgb(0.98,0.98,0.5) id:pleistocene value:rgb(0.999999,0.95,0.68) id:holocene value:rgb(0.999,0.95,0.88) BarData= bar:eratop bar:space bar:periodtop bar:space bar:NAM1 bar:NAM2 bar:space bar:period bar:space bar:era PlotData= align:center textcolor:black fontsize:M mark:(line,black) width:25 shift:(7,-4) bar:periodtop from: -65.5 till: -55.8 color:paleocene text:

Paleocene The Paleocene, ( ) or Palaeocene, is a geological epoch (geology), epoch that lasted from about 66 to 56 mya (unit), million years ago (mya). It is the first epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), E ...

from: -55.8 till: -33.9 color:eocene text:

Eocene The Eocene ( ) Epoch is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene' ...

from: -33.9 till: -23.03 color:oligocene text:

Oligocene The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but the ...

from: -23.03 till: -5.332 color:miocene text:

Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recen ...

from: -5.332 till: -2.588 color:pliocene text: Plio. from: -2.588 till: -0.0117 color:pleistocene text:

Pleist. The Pleistocene ( , often referred to as the ''Ice age'') is the geological epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed in ...

from: -0.0117 till: 0 color:holocene text: H. bar:eratop from: -65.5 till: -23.03 color:paleogene text:

Paleogene The Paleogene ( ; British English, also spelled Palaeogene or Palæogene; informally Lower Tertiary or Early Tertiary) is a geologic period, geologic period and system that spans 43 million years from the end of the Cretaceous Period million yea ...

from: -23.03 till: -2.588 color:neogene text:

Neogene The Neogene ( ), informally Upper Tertiary or Late Tertiary, is a geologic period and system that spans 20.45 million years from the end of the Paleogene Period million years ago ( Mya) to the beginning of the present Quaternary Period Mya. ...

from: -2.588 till: 0 color:quaternary text: Q. PlotData= align:left fontsize:M mark:(line,white) width:5 anchor:till align:left color:oligocene bar:NAM1 from: -33.9 till: 0 text: Scarus PlotData= align:center textcolor:black fontsize:M mark:(line,black) width:25 bar:period from: -65.5 till: -55.8 color:paleocene text: