Cichla temensis
| Cichla temensis | |
|---|---|
| |
Scientific classification
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| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Actinopterygii |
| Order: | Cichliformes |
| Family: | Cichlidae |
| Genus: | Cichla |
| Species: | C. temensis
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| Binomial name | |
| Cichla temensis Humboldt,1821
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| Synonyms | |
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Cichla temensis,thespeckled peacock bass,painted pavon,royal pavon,speckled pavon,three-barred peacock bass,orstriped tucunare,is a very largeSouth American cichlid.Reaching nearly 1 m (3.3 ft) in length, it is the largest cichlid of theAmericas,and one of thelargest extant cichlidsin the world. It is an importantpredatorin its native waterways, as well as a prizedfood fishandgame fish,which has led to a number of attemptedintroductionsoutside of its native range.
Description
[edit]C. temensisresembles otherpeacock bassspecies, but is generally more elongate and slender in body shape.[2]It is one of the largest cichlids in the world, reaching a maximum recorded length of 99 centimetres (39 in) and 12.2 kg (27 lb) in weight,[3][4]with only the Africangiant cichlid(Boulengerochromis microlepis) possibly reaching similar proportions.[5] C. temensisis characterized by possessing a post-orbitalband(the dark marking between the eye and the opening of thegills), as opposed to otherCichlaspecies which have either irregular blotches or lack them entirely. It is closest in overall patterning toC. pinimaandC. vazzoleri.[3]
Adults are highly variable in colour pattern, which has historically caused confusion; some authors speculated that the variants were aseparate speciesorsexual dimorphism.Only in 2012 was it firmly established that the differing colormorphswereseasonal;dark individuals with dense, light-hued speckles - called the speckled peacock ortucunaré paca- are the non-breeding individuals, while breeding adults - the three-barred peacock ortucunaré açu- lose the pale speckles entirely but develop agolden-olivecoloration whichcontrastshighly with the dark bars on their flanks, and a vibrantly coloredventralregion. During the breeding season, some males also develop abulbous forehead;or the nuchal hump, which is the only visible point of difference between the genders. The study also distinguished 2 other morphs, or grades, intermediate between the two mentioned prior. The 4 distinct grades were confirmed not to be the result of sexual dimorphism orregional variationthrough analysis ofmorphologyandgenetics.This variation in pattern is greater than what was observed between individuals ofC. orinocensisandC. monoculus.[6]
Distribution
[edit]
C. temensisis native to theOrinocoandRio Negrobasins, as well as several smaller rivers in the centralAmazon(Uatumã,Preto da Eva,Puraquequara,andTefé), inBrazil,Colombia,Venezuela,andGuyana.[3][2]
Introductionattempts have been made outside its native range, but it has not managed to become established inFloridaorTexasdue to extreme temperatures.[7][8]In contrast, it has flourished in tropicalSingapore[9][unreliable source?][8]andMalaysia.[10][unreliable source?]
Biology
[edit]The species isbenthopelagic,foundnear the shorelineoflagoonsand areas of the mainriver channelwith sandy or rocky banks.[3]In itsnative range,it is essentially restricted toblackwater riversand their tributaries.[2]They are comfortable in waterways with little cover, but non-breeding individuals may shelter near submerged wooden debris to avoid predation.[11][4]The species had mostly been studied during the dry season; its habits during the rainy season are less known.C. temensisare largely sedentary, but occasionally, some individuals are known to have migrated acrossflood plainsto other rivertributariesduring the rainy season.[12][4]
Feeding
[edit]C. temensisis adiurnalpredator,hunting fishthat it can swallow whole; it has been described as a potentialkeystone predator.[4]The coloration of the non-breedingtucunaré paca,a dark olive with extensive speckling all over, is theorized to provide an excellentcamouflagein thetannin-stained waters and the dappled light in theflooded forests,allowing it toambushprey in the tangled environs.[6]Small prey items include the tetraHemigrammus analis,Nannostomuspencil fish,anostomids,andpike cichlids.C. temensisis noted to hunt larger prey than othersympatricpeacock bass, hunting down a variety of fish such as the characiformesSemaprochilodus kneriandAcestrorhynchus heterolepis,Pimelodella sp.,armoured catfish,andcichlidsincludingsmaller peacock bass,although cannibalism might be more prevalent in fish stuck in isolated lagoons and reservoirs during the dry season, and the exact species of consumed peacock bass cannot be determined. Juvenile prochilods onmigrationare preyed on heavily by theopportunisticpeacock bass, at times comprising nearly half of thebiomassconsumed byC. temensis.This glut of food allows the peacock bass to reach ahealthy breeding condition.[3][13][11][14]
Spawning
[edit]
Cichla temensisbegin breeding at the end of thedry season,and part of the population likely continues breeding in the ensuing rising-water period andrainy season.Due to strongseasonal variationand extent of providedparental care,the species is typically restricted to breeding once a year in its naturalflood-pulse riverhabitat. Thetucunaré açuare visibly "blockier" in appearance than non-breeding adults, having a higher ratio of height:standard length;some of this is due to the formation offat depositson the body.C. temensismay begin breeding at atotal lengthof ~300 millimetres (12 in); males tend to be bigger than their partners, ranging from ~20% to more than 300% the weight of the female.[4]
Pairs prepare a site with adequatehardscape- such as a rock or live or dead standing tree - at a depth of 1–1.5 metres (3.3–4.9 ft) to adhere their eggs to. The male clears the area of detritus and may dig small pits to position the newly-hatched larvae. The female'sfecundityranges from under 2000 eggs to over 10000, which may be correlated to her body mass. While they do notmouthbroodtheirfrylike some other cichlids, one or both parents vigilantly guard their brood - and the subsequentschoolof fry - from potential predators,fastingall throughout this period. The fry hatch after 48 hours, and become free swimming after 2-3 days of absorbing theiryolk.Theplanktivorousfry are guarded for about 2 months or until they reach about 60 mmstandard length,after which they disperse and begin their independent lives. Dispersed juvenile fish may form shoals with their fellows.[6][13][4]Peacock bass are prone to interspecific hybridization;Cichla temensisitself has been found to naturally hybridize withCichla monoculusin the Central Amazon.[15]
Natural threats
[edit]Theamazon river dolphinand the piranhaSerrasalmus manuelihave been noted to attack various species of peacock bass, includingC. temensis,that were hooked or beingreleased.[11]Additionally,piscivorous snake[disambiguation needed]s,black caiman,andgiant river otteralso preys onC. temensis.[4]This peacock bass isparasitizedby the crustaceansAmazolernaea sanneraeandArgulus multicoloralong with thetrematodesAspidocotylus cochleariformisandClinostomum heluans.[16]
Commercial value
[edit]
C. temensisis fished bothcommerciallyand forsport;it is a populargamefishakin to other peacock bass due to its energetic fight when hooked. Fishing for peacock bass is regulated in Florida, althoughC. temensisitself was not successfully established and was not restocked.[17][8]The species, alongside other peacock bass, is fished intensively in its native range, but the effects of this fishery is not well studied despite its importance; some authorities deem it as the most important inland fishery of South America, but research into distinctstocksare ongoing.[4][12][18]
References
[edit]
- ^Frederico, R.G. (2023)."Cichla temensis".IUCN Red List of Threatened Species.2023:e.T164491891A164491901.doi:10.2305/IUCN.UK.2023-1.RLTS.T164491891A164491901.en.Retrieved2 January2024.
- ^abcKullander, Sven; Efrem Ferreira (2006). "A review of the South American cichlid genusCichla,with descriptions of nine new species (Teleostei: Cichlidae) ".Ichthyological Explorations of Freshwaters.17(4).
- ^abcdeFroese, Rainer;Pauly, Daniel (eds.)."Cichla temensis".FishBase.October 2017 version.
- ^abcdefghReiss, Paul (2015).Aspects of the life history of Cichla temensis (Perciformes: Cichlidae) and its relationship to the Amazon Basin's flood pulse.Rutgers University Libraries(Thesis).Rutgers University.doi:10.7282/T32B911F.Retrieved5 July2024.
- ^"The 10 biggest cichlids".Practical Fishkeeping. 13 June 2016.Retrieved17 October2017.
- ^abcReiss, Paul; Kenneth W. Able; Mario S. Nunes; Tomas Hrbek (2012)."Color pattern variation in Cichla temensis (Perciformes: Cichlidae): resolution based on morphological, molecular, and reproductive data".Neotrop. Ichthyol.10(1): 59–70.doi:10.1590/S1679-62252012000100006.
- ^Nico, L. (2011).Cichla temensis.USGS,Nonindigenous Aquatic Species Database,Gainesville, FL,USAA
- ^abc"Speckled Pavon (Cichla temensis) Ecological Risk Screening Summary"(PDF).fws.gov.US Fish and Wildlife Service.Retrieved5 July2024.
- ^"Peacock Bass (introduced)".Ecology Asia.Retrieved17 October2017.
- ^"Peacock Bass Fishing in Malaysia".SFA.Sport Fishin Asia.Retrieved5 July2024.
- ^abcJepsen, D. B.; Winemiller, K. O.; Taphorn, D. C. (1997)."Temporal patterns of resource partitioning among Cichla species in a Venezuelan blackwater river".Wiley Online Library.51(6).Journal of Fish Biology:1085–1108.Bibcode:1997JFBio..51.1085J.doi:10.1111/j.1095-8649.1997.tb01129.x.Retrieved5 July2024.
- ^abWillis, Stuart C.; Winemiller, Kirk O.; Montaña, Carmen G.; Macrander, Jason; Reiss, Paul; Farias, Izeni P.; Orti, Guillermo."Population genetics of the speckled peacock bass (Cichla temensis), South America's most important inland sport fishery"(PDF).aquaticecology.tamu.edu.Conservation Genetics.Retrieved6 July2024.
- ^abWinemiller, Kirk O.; Taphorn, Donald C.; Barbarino-Duque, Anielo (1997)."Ecology of Cichla (Cichlidae) in Two Blackwater Rivers of Southern Venezuela".Copeia(4).Copeia:690–696.doi:10.2307/1447287.JSTOR1447287.Retrieved5 July2024.
- ^Winemiller, Kirk O.; Jepsen, David B."Migratory Neotropical Fish Subsidize Food Webs of Oligotrophic Blackwater Rivers"(PDF).Winemiller Aquatic Ecology Lab.Texas A&M University.Retrieved5 July2024.
- ^Teixeira, Aylton Saturnino; de Oliveira, Suzana da Silva (2005)."Evidence for a natural hybrid of peacock bass (Cichla monoculus vs Cichla temensis) based on esterase electrophoretic patterns".PubMed.4(1).Genetic Molecular Research:74–83.PMID15841438.Retrieved5 July2024.
- ^"Cichla temensis Humboldt, 1821".WoRMS.World Register of Marine Species.Retrieved5 July2024.
- ^Inchausti, Max."Peacock Bass Fishing: A Beginner's Guide".Field & Stream.Retrieved5 July2024.
- ^Lubich, Chiara; Campos, Caroline; Freitas, Carlos; Siqueira-Souza, Flávia (2021)."Effects of Fishing on the Population of Speckled Pavon Cichla temensis in the Middle Negro River (Amazonas State, Brazil): A Decrease in the Size of the Trophy Fish?".Transactions of the American Fisheries Society.150(6).American Fisheries Society:667–678.Bibcode:2021TrAFS.150..667L.doi:10.1002/tafs.10329.Retrieved6 July2024.