''Acropora'' is a genus of small polyp stony

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 se ...

in the phylum

Cnidaria Cnidaria () is a phylum under kingdom Animalia containing over 11,000 species of aquatic animals found both in freshwater and marine environments, predominantly the latter. Their distinguishing feature is cnidocytes, specialized cells that ...

. Some of its

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriat ...

are known as table coral,

elkhorn coral Elkhorn coral (''Acropora palmata'') is an important reef-building coral in the Caribbean. The species has a complex structure with many branches which resemble that of elk antlers; hence, the common name. The branching structure creates habit ...

, and staghorn coral. Over 149 species are described. ''Acropora'' species are some of the major reef corals responsible for building the immense calcium carbonate substructure that supports the thin living skin of a reef.

Anatomy and distribution

Depending on the species and location, ''Acropora'' species may grow as plates or slender or broad branches. Like other corals, ''Acropora'' corals are colonies of individual polyps, which are about 2 mm across and share tissue and a

nerve net A nerve net consists of interconnected neurons lacking a brain or any form of cephalization. While organisms with bilateral body symmetry are normally associated with a condensation of neurons or, in more advanced forms, a central nervous syst ...

. The polyps can withdraw back into the coral in response to movement or disturbance by potential predators, but when undisturbed, they protrude slightly. The polyps typically extend further at night to help capture plankton and organic matter from the water. The species are distributed in the Indo-Pacific (over 100 species) and Caribbean (3 species). However, the true number of species is unknown: firstly, the validity of many of these species is questioned as some have been shown to represent hybrids, for example ''Acropora prolifera''; and secondly, some species have been shown to represent cryptic species complexes.

Threats

Symbiodinium : ''This is about the genus sometimes called Zoox. For the company, see Zoox (company)'' ''Symbiodinium'' is a genus of dinoflagellates that encompasses the largest and most prevalent group of endosymbiotic dinoflagellates known. These unicell ...

'',

symbiotic Symbiosis (from Greek , , "living together", from , , "together", and , bíōsis, "living") is any type of a close and long-term biological interaction between two different biological organisms, be it mutualistic, commensalistic, or para ...

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 micr ...

, live in the corals'

cell Cell most often refers to: * Cell (biology), the functional basic unit of life Cell may also refer to: Locations * Monastic cell, a small room, hut, or cave in which a religious recluse lives, alternatively the small precursor of a monastery ...

s and produce energy for the animals through

photosynthesis Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that, through cellular respiration, can later be released to fuel the organism's activities. Some of this chemical energy is stored in ...

. Environmental destruction has led to a dwindling of populations of ''Acropora'', along with other coral species. ''Acropora'' is especially susceptible to

bleaching Bleach is the generic name for any chemical product that is used industrially or domestically to remove color (whitening) from a fabric or fiber or to clean or to remove stains in a process called bleaching. It often refers specifically, to ...

when stressed. Bleaching is due to the loss of the coral's zooxanthellae, which are a golden-brown color. Bleached corals are stark white and may die if new ''Symbiodinium'' cells cannot be assimilated. Common causes of bleaching and coral death include pollution, abnormally warm water temperatures, increased

ocean acidification Ocean acidification is the reduction in the pH value of the Earth’s ocean. Between 1751 and 2021, the average pH value of the ocean surface has decreased from approximately 8.25 to 8.14. The root cause of ocean acidification is carbon dioxid ...

, sedimentation, and eutrophication. In 2014 the U.S. Fish and Wildlife Service listed ten ''Acropora'' species as 'threatened'.

Reef-keeping

Most ''Acropora'' species are brown or green, but a few are brightly colored, and those rare corals are prized by aquarists. Captive propagation of ''Acropora'' is widespread in the reef-keeping community. Given the right conditions, many ''Acropora'' species grow quickly, and individual colonies can exceed a meter across in the wild. In a well-maintained reef aquarium, finger-sized fragments can grow into medicine ball-sized colonies in one to two years. Captive specimens are steadily undergoing changes due to selection which enable them to thrive in the home aquarium. In some cases, fragments of captive specimens are used to repopulate barren reefs in the wild. ''Acropora'' species are challenging to keep in a home aquarium. They require bright light, stable temperatures, regular addition of calcium and alkalinity supplements, and clean, turbulent water. Common parasites of colonies in

reef aquarium A reef aquarium or reef tank is a marine aquarium that prominently displays live corals and other marine invertebrates as well as fish that play a role in maintaining the tropical coral reef environment. A reef aquarium requires appropriatel ...

s are "Acropora-eating flatworms" ''Amakusaplana acroporae'', and "red bugs" ('' Tegastes acroporanus'').

Species

The following species are recognised in the genus ''Acropora'': *'' Acropora abrolhosensis'' Veron, 1985 *'' Acropora abrotanoides'' (Lamarck, 1816) *'' Acropora acervata'' (Dana, 1846) *'' Acropora aculeus'' (Dana, 1846) *'' Acropora acuminata'' (Verrill, 1864) *'' Acropora alvarezi''† Wallace, 2008 *'' Acropora anglica''† (Duncan, 1866) *'' Acropora anthocercis'' (Brook, 1893) *'' Acropora arabensis'' Hodgson and Carpenter, 1995 *'' Acropora arafura'' Wallace, Done & Muir, 2012 *'' Acropora aspera'' (Dana, 1846) *'' Acropora austera'' (Dana, 1846) *'' Acropora awi''

Wallace Wallace may refer to: People * Clan Wallace in Scotland * Wallace (given name) * Wallace (surname) * Wallace (footballer, born 1986), full name Wallace Fernando Pereira, Brazilian football left-back * Wallace (footballer, born 1987), full name ...

and Wolstenholme, 1998 *'' Acropora bartonensis''† Wallace, 2008 *''

Acropora batunai ''Acropora batunai'' is a species of acroporid coral that was described by Carden Wallace in 1997. Found in protected, shallow reefs, it occurs in a marine environment at depths of up to . The species is rated as vulnerable on the IUCN Red L ...

, 1997 *'' Acropora borneoensis''† (Felix, 1921) *'' Acropora branchi'' Riegl, 1995 *'' Acropora britannica''† Wallace, 2008 *'' Acropora bushyensis'' Veron and Wallace, 1984 *'' Acropora capillaris'' (Klunzinger, 1879) *'' Acropora cardenae'' Wells, 1986 *'' Acropora carduus'' (Dana, 1846) *'' Acropora caroliniana'' Nemenzo, 1976 *'' Acropora cerealis'' (Dana, 1846) *''

Acropora cervicornis The staghorn coral (''Acropora cervicornis'') is a branching, stony coral with cylindrical branches ranging from a few centimetres to over two metres in length and height. It occurs in back reef and fore reef environments from depth. The upp ...

'' (Lamarck, 1816) - staghorn coral *'' Acropora chesterfieldensis'' Veron and Wallace, 1984 *'' Acropora clathrata'' (Brook, 1891) *''

Acropora cytherea ''Acropora cytherea'' is a stony coral which forms horizontal table like structures. It occurs in the Indo-Pacific Ocean in areas with little wave action, favouring back reef environments from depth. Description ''Acropora cytherea'' is a col ...

'' (Dana, 1846) *'' Acropora darrellae''† Santodomingo, Wallace & Johnson, 2015 *'' Acropora deformis''† (Michelin, 1840) *'' Acropora dendrum'' (Bassett-Smith, 1890) *'' Acropora derawaensis'' Wallace, 1997 *'' Acropora desalwii'' Wallace, 1994 *'' Acropora digitifera'' (Dana, 1846) *'' Acropora divaricata'' (Dana, 1846) *'' Acropora donei'' Veron and Wallace, 1984 *'' Acropora downingi'' Wallace, 1999 *'' Acropora duncani''† (Reuss, 1866) *''

Acropora echinata ''Acropora echinata'' is a species of acroporid coral that was first described by Dana in 1846. Found in shallow, tropical, sheltered reefs in marine environments, it is found at depths of in clear water. The species is listed as vulnerable o ...

'' (Dana, 1846) *'' Acropora elegans'' (Milne-Edwards and Haime, 1860) *'' Acropora elenae''† Santodomingo, Wallace & Johnson, 2015 *'' Acropora elseyi'' (Brook, 1892) *'' Acropora emanuelae''† Santodomingo, Wallace & Johnson, 2015 *'' Acropora eurystoma'' (Klunzinger, 1879) *'' Acropora fastigata'' Nemenzo, 1967 *'' Acropora fennemai''† (Gerth, 1921) *'' Acropora fenneri'' Veron, 2000 *'' Acropora filiformis'' Veron, 2000 *'' Acropora florida'' (Dana, 1846) *'' Acropora gemmifera'' (Brook, 1892) *'' Acropora glauca'' (Brook, 1893) *'' Acropora globiceps'' (Dana, 1846) *'' Acropora gomezi'' Veron, 2000 *'' Acropora grandis'' (Brook, 1892) *''

Acropora granulosa ''Acropora granulosa'' is a species of acroporid coral found in the northern and southwest Indian Ocean, the Red Sea, Australia, the East China Sea, Japan, the oceanic central and western Pacific Ocean, and the central Indo-Pacific. It occurs in ...

'' (Milne-Edwards and Haime, 1860) *'' Acropora haidingeri''† (Reuss, 1864) *'' Acropora halmaherae'' Wallace and Wolstenholme, 1998 *'' Acropora hasibuani''† Santodomingo, Wallace & Johnson, 2015 *'' Acropora hemprichii'' (Ehrenberg, 1834) *'' Acropora herklotsi''† (Reuss, 1866) *'' Acropora hoeksemai'' Wallace, 1997 *'' Acropora horrida'' (Dana, 1846) *'' Acropora humilis'' (Dana, 1846) *'' Acropora hyacinthus'' (Dana, 1846) *'' Acropora indonesia'' Wallace, 1997 *'' Acropora intermedia'' (Brook, 1891) *'' Acropora jacquelineae'' Wallace, 1994 *'' Acropora japonica'' Veron, 2000 *'' Acropora kimbeensis'' Wallace, 1999 *'' Acropora kirstyae'' Veron and Wallace, 1984 *'' Acropora kosurini'' Wallace, 1994 *'' Acropora lamarcki'' Veron, 2000 *'' Acropora latistella'' (Brook, 1892) *'' Acropora laurae''† Santodomingo, Wallace & Johnson, 2015 *'' Acropora lavandulina''† (Michelin, 1840) *'' Acropora listeri'' (Brook, 1893) *'' Acropora loisetteae'' Wallace, 1994 *'' Acropora lokani'' Wallace, 1994 *'' Acropora longicyathus'' (Milne-Edwards and Haime, 1860) *'' Acropora loripes'' (Brook, 1892) *'' Acropora lovelli'' Veron and Wallace, 1984 *'' Acropora lutkeni'' Crossland, 1952 *'' Acropora macrocalyx''† Wallace & Bosselini, 2015 *'' Acropora microclados'' (Ehrenberg, 1834) *'' Acropora microphthalma'' (Verrill, 1869) *'' Acropora millepora'' (Ehrenberg, 1834) *'' Acropora monticulosa'' (Brueggemann, 1879) *'' Acropora mossambica'' Riegl, 1995 *'' Acropora multiacuta'' Nemenzo, 1967 *'' Acropora muricata'' (Linnaeus, 1758) *'' Acropora nana'' (Studer, 1878) *'' Acropora nasuta'' (Dana, 1846) *'' Acropora natalensis'' Riegl, 1995 *'' Acropora ornata''† (DeFrance, 1828) *'' Acropora palmata'' (Lamarck, 1816) - elkhorn coral *'' Acropora palmerae'' Wells, 1954 *'' Acropora paniculata'' Verrill, 1902 *'' Acropora papillare'' Latypov, 1992 *'' Acropora pectinata'' Veron, 2000 *'' Acropora pharaonis'' (Milne-Edwards and Haime, 1860) *'' Acropora pichoni'' Wallace, 1999 *'' Acropora piedmontensis''† Wallace & Bosselini, 2015 *'' Acropora plumosa'' Wallace and Wolstenholme, 1998 *'' Acropora polystoma'' (Brook, 1891) *''

Acropora prolifera ''Acropora prolifera'', the fused staghorn coral, is a branching, colonial, stony coral found in shallow parts of the Caribbean Sea, the Bahamas and southern Florida. Description ''Acropora prolifera'' is very similar to staghorn coral (''A ...

'' (Lamarck, 1816) - fused staghorn coral *'' Acropora proteacea''† Wallace, 2008 *'' Acropora proximalis'' Veron, 2000 *'' Acropora pulchra'' (Brook, 1891) *'' Acropora renemai''† Santodomingo, Wallace & Johnson, 2015 *'' Acropora retusa'' (Dana, 1846) *'' Acropora ridzwani'' Ditlev, 2003 *'' Acropora robusta'' (Dana, 1846) *'' Acropora roemeri''† (Duncan, 1866) *'' Acropora rongelapensis'' Richards & Wallace, 2004 *'' Acropora roseni'' Wallace, 1999 *'' Acropora rudis'' (Rehberg, 1892) *'' Acropora rufa'' Veron, 2000 *'' Acropora russelli'' Wallace, 1994 *'' Acropora salentina''† Wallace & Bosselini, 2015 *'' Acropora samoensis'' (Brook, 1891) *'' Acropora sarmentosa'' (Brook, 1892) *'' Acropora secale'' (Studer, 1878) *'' Acropora selago'' (Studer, 1878) *'' Acropora seriata'' (Ehrenberg, 1834) *'' Acropora serrata'' Lamarck *'' Acropora simplex'' Wallace and Wolstenholme, 1998 *'' Acropora sirikitiae'' Wallace, Phongsuwan & Muir, 2012 *'' Acropora slovenica''† Wallace & Bosselini, 2015 *'' Acropora solanderi''† (Defrance, 1828) *'' Acropora solitaryensis'' Veron and Wallace, 1984 *'' Acropora sordiensis'' Riegl, 1995 *'' Acropora spathulata'' (Brook, 1891) *''

Acropora speciosa ''Acropora speciosa'' is a species of acroporid coral found in the Red Sea, the Gulf of Aden, the southwest and northern Indian Ocean, the central Indo-Pacific, Southeast Asia, Japan, the East China Sea The East China Sea is an arm of ...

'' (Quelch, 1886) *'' Acropora spicifera'' (Dana, 1846) *'' Acropora squarrosa'' (Ehrenberg, 1834) *''

Acropora striata ''Acropora striata'' is a species of acroporid coral found in the southwest Indian Ocean, the central Indo-Pacific, Japan and the East China Sea. It can also be found in the Marshall Islands, the Society Islands, the Cook Islands ) , i ...

'' (Verrill, 1866) *'' Acropora subglabra'' (Brook, 1891) *'' Acropora subulata'' (Dana, 1846) *'' Acropora suharsonoi'' Wallace, 1994 *'' Acropora sukarnoi'' Wallace, 1997 *'' Acropora tanegashimensi'' -s Veron, 1990 *'' Acropora tenella'' (Brook, 1892) *''

Acropora tenuis ''Acropora tenuis'' is a species of acroporid coral found in the Red Sea, the Gulf of Aden, the southwest, northwest and northern Indian Ocean, the Persian Gulf, the central Indo-Pacific, Australia, Southeast Asia, Japan, the East China Sea ...

'' (Dana, 1846) *'' Acropora torihalimeda'' Wallace, 1994 *'' Acropora tortuosa'' (Dana, 1846) *'' Acropora tuberculosa'' (Milne Edwards, 1860) *'' Acropora turaki'' Wallace, 1994 *'' Acropora valenciennesi'' (Milne-Edwards and Haime, 1860) *'' Acropora valida'' (Dana, 1846) *'' Acropora variolosa'' (Klunzinger, 1879) *'' Acropora vaughani'' Wells, 1954 *'' Acropora verweyi'' Veron and Wallace, 1984 *'' Acropora walindii'' Wallace, 1999 *'' Acropora willisae'' Veron and Wallace, 1984 *'' Acropora wilsonae''† Wallace, 2008 *'' Acropora yongei'' Veron and Wallace, 1984

References

External links