Groupers are a diverse group of marine

ray-finned fish Actinopterygii (; ), members of which are known as ray-finned fish or actinopterygians, is a class of bony fish that comprise over 50% of living vertebrate species. They are so called because of their lightly built fins made of webbings of sk ...

in the family Epinephelidae, in the order

Perciformes Perciformes (), also called the Acanthopteri, is an order or superorder of ray-finned fish in the clade Percomorpha. ''Perciformes'' means " perch-like". Among the well-known members of this group are perches and darters ( Percidae), and als ...

. Groupers were long considered a

subfamily In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end botanical subfamily names with "-oideae", and zo ...

of the seabasses in

Serranidae Serranidae is a large family (biology), family of fishes belonging to the order Perciformes. The family contains about 450 species in 65 genera, including the sea basses and the groupers (subfamily Epinephelinae). Although many species are small, ...

, but are now treated as distinct. Not all members of this family are called "groupers". The common name "grouper" is usually given to fish in one of two large

genera Genus (; : genera ) is a taxonomic rank above species and below family as used in the biological classification of living and fossil organisms as well as viruses. In binomial nomenclature, the genus name forms the first part of the binomial s ...

: ''

Epinephelus ''Epinephelus'' is a genus of marine ray-finned fish, groupers from the subfamily Epinephelinae, part of the family Serranidae, which also includes the anthias and sea basses. They are predatory fish, largely associated with reefs and are fo ...

'' and '' Mycteroperca''. In addition, the species classified in the small genera ''Anyperidon'', ''Cromileptes'', ''Dermatolepis'', ''Graciela'', ''Saloptia'', and ''Triso'' are also called "groupers". Fish in the genus '' Plectropomus'' are referred to as "coral groupers". These genera are all classified in the subfamily Epiphelinae. However, some of the hamlets (genus ''Alphestes''), the hinds (genus ''Cephalopholis''), the lyretails (genus ''Variola''), and some other small genera (''Gonioplectrus'', ''Niphon'', ''Paranthias'') are also in this subfamily, and occasional species in other serranid genera have common names involving the word "grouper". Nonetheless, the word "grouper" on its own is usually taken as meaning the family Epinephelidae.

Description

Groupers are

teleost Teleostei (; Ancient Greek, Greek ''teleios'' "complete" + ''osteon'' "bone"), members of which are known as teleosts (), is, by far, the largest group of ray-finned fishes (class Actinopterygii), with 96% of all neontology, extant species of f ...

s, typically having a stout body and a large mouth. They are not built for long-distance, fast swimming. They can be quite large: in length, over a meter. The largest is the Atlantic goliath grouper (''Epinephelus itajara'') which has been weighed at and a length of , though in such a large group, species vary considerably. They swallow prey rather than biting pieces off of them. They do not have many teeth on the edges of their jaws, but they have heavy crushing tooth plates inside the

pharynx The pharynx (: pharynges) is the part of the throat behind the human mouth, mouth and nasal cavity, and above the esophagus and trachea (the tubes going down to the stomach and the lungs respectively). It is found in vertebrates and invertebrates ...

. They habitually eat

fish A fish (: fish or fishes) is an aquatic animal, aquatic, Anamniotes, anamniotic, gill-bearing vertebrate animal with swimming fish fin, fins and craniate, a hard skull, but lacking limb (anatomy), limbs with digit (anatomy), digits. Fish can ...

octopus An octopus (: octopuses or octopodes) is a soft-bodied, eight-limbed mollusc of the order Octopoda (, ). The order consists of some 300 species and is grouped within the class Cephalopoda with squids, cuttlefish, and nautiloids. Like oth ...

es, and

crustacean Crustaceans (from Latin meaning: "those with shells" or "crusted ones") are invertebrate animals that constitute one group of arthropods that are traditionally a part of the subphylum Crustacea (), a large, diverse group of mainly aquatic arthrop ...

s. Some species prefer to ambush their prey, while others are active predators. Reports of fatal attacks on humans by the largest species, such as the giant grouper (''Epinephelus lanceolatus''), are unconfirmed. Their mouths and

gill A gill () is a respiration organ, respiratory organ that many aquatic ecosystem, aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow r ...

s form a powerful vacuum that pulls their prey in from a distance. They also use their mouths to dig into sand to form their shelters under big rocks, jetting it out through their gills. Research indicates roving coralgroupers (''Plectropomus pessuliferus'') sometimes cooperate with giant morays in hunting. Groupers are also one of the only animals that eat invasive red lionfish.

Systematics

Etymology

The word "grouper" is from the Portuguese name, ''garoupa'', which has been speculated to come from an indigenous South American language. In Australia, "groper" is used instead of "grouper" for several species, such as the Queensland grouper (''Epinephelus lanceolatus''). In New Zealand, "groper" refers to a type of wreckfish, ''Polyprion oxygeneios'', which goes by the name '' hapuka'' (from the

Māori language Māori (; endonym: 'the Māori language', commonly shortened to ) is an Eastern Polynesian languages, Eastern Polynesian language and the language of the Māori people, the indigenous population of mainland New Zealand. The southernmost membe ...

). In the

Philippines The Philippines, officially the Republic of the Philippines, is an Archipelagic state, archipelagic country in Southeast Asia. Located in the western Pacific Ocean, it consists of List of islands of the Philippines, 7,641 islands, with a tot ...

, groupers are generally known as ''lapu-lapu'' in

Luzon Luzon ( , ) is the largest and most populous List of islands in the Philippines, island in the Philippines. Located in the northern portion of the List of islands of the Philippines, Philippine archipelago, it is the economic and political ce ...

, while in the

Visayas The Visayas ( ), or the Visayan Islands (Bisayan languages, Visayan: ''Kabisay-an'', ; Filipino language, Filipino: ''Kabisayaan'' ), are one of the three Island groups of the Philippines, principal geographical divisions of the Philippines, a ...

and

Mindanao Mindanao ( ) is the List of islands of the Philippines, second-largest island in the Philippines, after Luzon, and List of islands by population, seventh-most populous island in the world. Located in the southern region of the archipelago, the ...

they are known as ''pugapo''. It is known as ''kerapu'' in both Indonesian and Malay. In the

Middle East The Middle East (term originally coined in English language) is a geopolitical region encompassing the Arabian Peninsula, the Levant, Turkey, Egypt, Iran, and Iraq. The term came into widespread usage by the United Kingdom and western Eur ...

, the fish is known as ' hammour', and is widely eaten, especially in the

Persian Gulf The Persian Gulf, sometimes called the Arabian Gulf, is a Mediterranean seas, mediterranean sea in West Asia. The body of water is an extension of the Arabian Sea and the larger Indian Ocean located between Iran and the Arabian Peninsula.Un ...

region. In Latin America, the fish is known as ' mero'. The species in the tribes Grammistini and Diploprionini secrete a mucus-like toxin in their skin called grammistin, and when they are confined in a restricted space and subjected to stress, the mucus produces a foam that is toxic to nearby fish. These fishes are often called soapfishes. They have been classified either as their own families or within subfamilies, although the fifth Edition of the ''Fishes of the World'' classifies these two groups as tribes within the subfamily Epinephelinae. However, '' Eschmeyer's Catalog of Fishes'' presently treats these as distinct families.

Classification

Based on '' Eschmeyer's Catalog of Fishes:'' * Family Epinephelidae Bleeker, 1874 (groupers) ** '' Aethaloperca'' Fowler, 1904 ** '' Alphestes'' Bloch & Schneider, 1801 ** '' Anyperodon'' Günther, 1859 ** '' Cephalopholis'' Bloch & Schneider, 1801 ** '' Chromileptes'' Swainson, 1839 ** '' Dermatolepis''

Gill A gill () is a respiration organ, respiratory organ that many aquatic ecosystem, aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow r ...

, 1861 ** ''

'' Bloch, 1793 ** '' Gonioplectrus'' Gill, 1862 ** '' Gracila'' Randall, 1964 ** '' Hyporthodus'' Gill, 1861 ** '' Mycteroperca'' Gill, 1862 ** '' Paranthias'' Guichenot, 1868 ** '' Plectropomus'' Pken, 1817 ** '' Saloptia'' J.L.B. Smith, 1964 ** '' Triso'' Randall, Johnson & Lowe, 1989 ** '' Variola'' Swainson, 1839

Reproduction

Groupers are mostly monandric protogynous hermaphrodites, i.e., they mature only as females and can change sex after sexual maturity.Erisman, B. E., M. T. Craig, and P. A. Hastings. 2009. A phylogenetic test of the size-advantage model: Evolutionary changes in mating behavior influence the loss of sex change in a fish lineage. American Naturalist 174:83-99.DeMartini, E. E., A. R. Everson and R. S. Nichols. 2011. Estimates of body sizes at maturation and sex change and the endemic Hawaiian grouper's spawning seasonality and sex ratio (''Hyporthodus queries'', f. Epinephelidae). Fishery Bulletin 109:123-134. Some species of groupers grow about a kilogram per year and are generally adolescents until they reach three kilograms when they become female. The largest males often control harems containing three to 15 females.Sadovy, Y. and P. L. Colin. 1995. Sexual development and sexuality in the Nassau grouper. Journal of Fish Biology 46:961-976. Groupers often pair spawn, which enables large males to competitively exclude smaller males from reproducing.Allsop, D. J. and S. A. West. 2003. Constant relative age and size at sex change for sequentially hermaphroditic fish. Journal of Evolutionary Biology 16:921-929.Munoz, R. C. and R. R. Warner. 2003. A new version of the size-advantage hypothesis for sex change: Incorporating sperm competition and size-fecundity skew. American Naturalist 161:749-761.Kuwamura, T. 2004. Sex change in fishes: Its process and evolutionary mechanism. Zoological Science 21:1248-1248. As such, if a small female grouper were to change sex before it could control a harem as a male, its fitness would decrease. If no male is available, the largest female that can increase fitness by changing sex will do so. However, some groupers are gonochoristic. Gonochorism, or a reproductive strategy with two distinct sexes, has evolved independently in groupers at least five times. The evolution of gonochorism is linked to group spawning high amounts of habitat cover.Erisman, B. E., J. A. Rosales-Cassian and P. A. Hastings. 2008. There is evidence of gonochorism in a grouper, ''Mycteroperca rosacea'', from the Gulf of California, Mexico. Environmental Biology of Fishes 82:23-33. Both group spawning and habitat cover increase the likelihood of a smaller male reproducing in the presence of large males. The fitness of male groupers in environments where competitive exclusion of smaller males is impossible is correlated with sperm production and thus

testicle A testicle or testis ( testes) is the gonad in all male bilaterians, including humans, and is Homology (biology), homologous to the ovary in females. Its primary functions are the production of sperm and the secretion of Androgen, androgens, p ...

size.Molloy, P. P., N. B. Goodwin, I. M. Cote, J. D. Reynolds, and M. J. G. Gage. 2007. Sperm competition and sex change: A comparative analysis across fishes. Evolution 61:640-652. Gonochoristic groupers have larger testes than protogynous groupers (10% of body mass compared to 1% of body mass), indicating the evolution of gonochorism increased male grouper fitness in environments where large males were unable to competitively exclude small males from reproducing.

Parasites

Like other fish, groupers harbor

parasite 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, including digeneans,

nematode The nematodes ( or ; ; ), roundworms or eelworms constitute the phylum Nematoda. Species in the phylum inhabit a broad range of environments. Most species are free-living, feeding on microorganisms, but many are parasitic. Parasitic worms (h ...

cestode Cestoda is a class of parasitic worms in the flatworm phylum (Platyhelminthes). Most of the species—and the best-known—are those in the subclass Eucestoda; they are ribbon-like worms as adults, commonly known as tapeworms. Their bodies co ...

monogenea Monogeneans, members of the class Monogenea, are a group of ectoparasitic flatworms commonly found on the skin, gills, or fins of fish. They have a direct lifecycle and do not require an intermediate host. Adults are hermaphrodites, meaning they ...

ns,

isopod Isopoda is an Order (biology), order of crustaceans. Members of this group are called isopods and include both Aquatic animal, aquatic species and Terrestrial animal, terrestrial species such as woodlice. All have rigid, segmented exoskeletons ...

s, and

copepod Copepods (; meaning 'oar-feet') are a group of small crustaceans found in nearly every freshwater and saltwater habitat (ecology), habitat. Some species are planktonic (living in the water column), some are benthos, benthic (living on the sedimen ...

s. A study conducted in

New Caledonia New Caledonia ( ; ) is a group of islands in the southwest Pacific Ocean, southwest of Vanuatu and east of Australia. Located from Metropolitan France, it forms a Overseas France#Sui generis collectivity, ''sui generis'' collectivity of t ...

has shown that

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 group ...

-associated groupers have about ten species of parasites per fish species. Species of '' Pseudorhabdosynochus'', monogeneans of the family

Diplectanidae The Diplectanidae are a family of monopisthocotylean monogeneans. They are all parasitic on the gills of fish (marine or freshwater). Diplectanids are small animals, generally around 1 mm in length. As parasites, they can be extremely numero ...

are typical of and especially numerous on groupers.

Modern use

Many groupers are important food fish; some are now farmed. Unlike most other fish species, which are chilled or frozen, groupers are usually sold alive in markets. Many species are popular

game fish Game fish, sport fish or quarry refer to popular fish species pursued by recreational fishing, recreational fishers (typically angling, anglers), and can be freshwater fish, freshwater or saltwater fish. Game fish can be fish as food, eaten aft ...

for sea-angling. Some species are small enough to be kept in aquaria, though even the small species are inclined to grow rapidly. Groupers are commonly reported as a source of ciguatera fish poisoning.

DNA barcoding DNA barcoding is a method of species identification using a short section of DNA from a specific gene or genes. The premise of DNA barcoding is that by comparison with a reference library of such DNA sections (also called " sequences"), an indiv ...

of grouper species might help control Ciguatera fish poisoning since fish are easily identified, even from meal remnants, with molecular tools.

Size

Malaysian newspaper '' The Star'' reported a grouper being caught off the waters near Pulau Sembilan in the

Strait of Malacca The Strait of Malacca is a narrow stretch of water, long and from wide, between the Malay Peninsula to the northeast and the Indonesian island of Sumatra to the southwest, connecting the Andaman Sea (Indian Ocean) and the South China Sea (Pa ...

in January 2008. Shenzhen News in China reported that a grouper swallowed a whitetip reef shark at the Fuzhou Sea World aquarium. In September 2010, a Costa Rican newspaper reported a grouper in Cieneguita, Limón. The weight of the fish was , and it was lured using one kilogram of bait. In November 2013, a grouper had been caught and sold to a hotel in Dongyuan, China. In August 2014, off Bonita Springs in

Florida Florida ( ; ) is a U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders the Gulf of Mexico to the west, Alabama to the northwest, Georgia (U.S. state), Georgia to the north, the Atlantic ...

(USA), a big grouper took in one gulp a 4-foot shark that an angler had caught.

References

External links

The Ultimate Guide to Fly Fishing for Grouper
*ARKive �
images and movies of the humpback grouper ''(Chromileptes altivelis)''
* {{Authority control Epinephelinae Serranidae Commercial fish Fish common names Cuisine of the Southern United States