Redbelly tilapia

{{Short description|Species of fish}} {{Confused|redbreast tilapia}} {{Speciesbox | image = St. Peter's Fish.jpg | image2 = Tizil u0.gif | status = LC | status_system = IUCN3.1 | status_ref = <ref name="iucn status 20 November 2021">{{cite iucn |author=Lalèyè, P. |date=2020 |title=''Coptodon zillii'' |volume=2020 |article-number=e.T183163A64508317 |doi=10.2305/IUCN.UK.2020-2.RLTS.T183163A64508317.en |access-date=20 November 2021}}</ref> | taxon = Coptodon zillii | authority = (Gervais, 1848) | synonyms = *''Acerina zillii'' Gervais, 1848 *''Chromis zillii'' (Gervais, 1848) *''Coptodus zillii'' (Gervais, 1848) *''Glyphisidon zillii'' (Gervais, 1848) *''Sarotherodon zillii'' (Gervais, 1848) *''Tilapia zillii'' (Gervais, 1848) *''Haligenes tristrami'' Günther, 1860 *''Chromis tristrami'' (Günther, 1860) *''Tilapia tristrami'' (Günther, 1860) *''Tilapia melanopleura'' Duméril, 1861 *''Chromis melanopleura'' (Duméril, 1861) *''Chromis andreae'' Günther, 1864 *''Chromis coeruleomaculatus'' Rochebrune, 1880 *''Chromis faidherbii'' Rochebrune, 1880 *''Chromis menzalensis'' Mitchell, 1895 *''Tilapia menzalensis'' (Mitchell, 1895) *''Tilapia multiradiata'' Holly, 1928 *''Tilapia shariensis'' Fowler, 1949 | synonyms_ref = <ref name = Fishbase>{{Fishbase|Coptodon|zillii|month=December|year=2019}}</ref> }}

The '''redbelly tilapia''' ('''''Coptodon zillii''''', syn. ''Tilapia zillii''), also known as the '''Zille's redbreast tilapia''' or '''St. Peter's fish''' (a name also used for other tilapia in Israel), is a species of fish in the cichlid family. This fish is found widely in fresh and brackish waters in the northern half of Africa and the Middle East.<ref name="iucn status 20 November 2021" /><ref name=fishbase>{{FishBase | genus = Coptodon | species = zillii | month = November | year = 2019}}</ref> Elsewhere in Africa, Asia, Australia and North America, it has been introduced as a food fish or as a control of aquatic vegetation. Where introduced, it sometimes becomes invasive, threatening the local ecology and species.<ref name=fishbase/><ref name=Genner2018>{{cite web | author1=Genner, M.J. | author2=G.F. Turner | author3=B.P. Ngatunga | year=2018 | title=A Guide to Tilapia Fishes of Tanzania | url=https://martingenner.weebly.com/uploads/1/6/2/5/16250078/tanzania_tilapia_guide_edition1_2018.pdf | access-date=10 November 2019 }}</ref><ref name=NASD>{{cite web | author1=Nico, L. | author2=M. Neilson | author3=B. Loftus | year=2019 | title=Tilapia zillii (Gervais, 1848) | url=https://nas.er.usgs.gov/queries/factsheet.aspx?speciesid=485 | publisher=U.S. Geological Survey, Nonindigenous Aquatic Species Database | access-date=10 November 2019 }}</ref><ref name=CABI>{{cite web | year=2019 | title=Tilapia zillii (redbelly tilapia) | url=https://www.cabi.org/isc/datasheet/61147 | publisher=CABI – Invasive Species Compendium | access-date=13 November 2019 }}</ref> The redbelly tilapia is an important food fish and sometimes aquacultured.<ref name=fishbase/><ref name=Genner2018/>

The species was named by Paul Gervais in honor of M. (probably Monsieur) Zill, a "distinguished naturalist" who collected the type specimen and sent it to Gervais.<ref name = ETYFish>{{cite web | url = http://www.etyfish.org/cichlidae7/ | title = Order CICHLIFORMES: Family CICHLIDAE: PSEUDOCRENILABRINAE (a-g) | access-date= 19 February 2021 | author1 = Christopher Scharpf | author2 = Kenneth J. Lazara | name-list-style = amp | work = The ETYFish Project Fish Name Etymology Database | publisher = Christopher Scharpf and Kenneth J. Lazara | date = 22 September 2018}}</ref>{{Failed verification|date=November 2021}}

==Native distribution and taxonomy== [[File:Coptodon zillii 291709306.jpg|left|thumb|223x223px|In Texas, as an introduced species.]] In Africa, the native range of the redbelly tilapia covers the northern half of the continent. In tropical West to Central Africa, from coastal southern Morocco and the Senegal River to the central Congo River basin, its range is almost continuous.<ref name=fishbase/><ref name=Clavero2017>{{cite journal | author1=Clavero, M. | author2=A. Qninba | author3=M. Riesco | author4=J. Esquivias | author5=J. Calzada | author6=M. Delibes | year=2017 | title=Moroccan desert rivers: fish on the arid extreme of Mediterranean streams | journal=Fishes in Mediterranean Environments | volume=003 | pages=1–21 | doi=10.29094/FiSHMED.2017.003 | doi-access=free }}</ref> In northeastern Africa the redbelly tilapia occurs throughout much of the Nile basin, from its delta in northern Egypt to Lake Albert in DR Congo–Uganda, as well Lake Turkana in Ethiopia–Kenya; it is not native to the other African Great Lakes, although it has been introduced to some of them.<ref name="iucn status 20 November 2021" /><ref name=fishbase/><ref name=Genner2018/> In the Maghreb and Sahara where fewer aquatic habitats are available, the range is much more spotty but with several relict populations in seasonal rivers, lakes and oases (gueltas).<ref name=Clavero2017/><ref name=Trape2016>{{cite journal | author=Trape, S. | year=2016 | title=A new cichlid fish in the Sahara: The Ounianga Serir lakes (Chad), a biodiversity hotspot in the desert | journal=Comptes Rendus Biologies | volume=339 | issue=11–12 | pages=529–536 | doi=10.1016/j.crvi.2016.08.003 | pmid=27720144 }}</ref> Outside Africa, its natural distribution is limited to the Jordan River system, including Lake Tiberias (Kinneret), in Israel, Jordan and Syria, as well as coastal systems in Israel.<ref name=fishbase/><ref name=Gophen2018>{{cite book | author=Gophen, M. | year=2018 | title=Ecological Research in the Lake Kinneret and Hula Valley (Israel) Ecosystems | pages=252–263 }}</ref>

Cichlids are numerous in Africa, but in parts of the redbelly tilapia's range it is one of the few members of the family. In the Maghreb and Sahara (excluding the species-rich Nile), the only others are the blue tilapia (''Oreochromis aureus'') and mango tilapia (''Sarotherodon galilaeus''), and a couple of ''Astatotilapia'' and ''Hemichromis'' species.<ref name=Clavero2017/><ref name=Trape2016/><ref name=Trape2018>{{cite journal | author=Trape, S. | year=2018 | title=Epiplatys bifasciatus (Steindachner, 1881) (Nothobranchiidae) and Hemichromis fasciatus Peters, 1852 (Cichlidae), two relict fish species in the Sahara desert | journal=Bonn Zoological Bulletin | volume=67 | issue=1 | pages=37–40 }}</ref> In Western Asia, the only other native cichlids are a few species of oreochromine tilapias and the Jordan mouthbrooder (''Astatotilapia flaviijosephi'').<ref name=Gophen2018/><ref name=Werner2004>{{cite journal | author1=Werner, N.Y. | author2=O. Mokady | year=2004 | title=Swimming out of Africa: mitochondrial DNA evidence for late Pliocene dispersal of a cichlid from Central Africa to the Levant | journal=Biological Journal of the Linnean Society | volume=82 | issue=1 | pages=103–109 | doi=10.1111/j.1095-8312.2004.00321.x | s2cid=55300630 | doi-access=free }}</ref>

Although genetic studies have shown that most populations of the redbelly tilapia are very closely related,<ref name=Dunz2013>{{cite journal | author1=Dunz, A.R. | author2=U.K. Schliewen | year=2013 | title=Molecular phylogeny and revised classification of the haplotilapiine cichlid fishes formerly referred to as "Tilapia" | journal=Molecular Phylogenetics and Evolution | volume=68 | issue=1 | pages=64–80 | doi=10.1016/j.ympev.2013.03.015 | pmid=23542002 }}</ref> a few from the outer margins of its range are of questionable taxonomic status and require further study. A population in the Kisangani region, although closely related, appears to be separate.<ref name=Dunz2013/> Similarly, those found in coastal northwestern Africa are genetically quite distinct from the other populations.<ref name=Clavero2017/> In the Nile system, it has been observed that populations in its delta, the northern White Nile and lakes near Fayum differ from each other in morphology and colors, but whether this is taxonomically significant is unclear. In contrast, the virtually unknown ''C. ismailiaensis'' of northeastern Egypt might only be an aberrant redbelly tilapia; it primarily differs in its unspotted tail.<ref name=Neumann2016>{{cite journal | author1=Neumann, D. | author2=H. Obermaier | author3=T. Moritz | year=2016 | title=Annotated checklist for fishes of the Main Nile Basin in the Sudan and Egypt based on recent specimen records (2006-2015) | journal=Cybium | volume=40 | issue=4 | pages=287–317 | doi=10.26028/cybium/2016-404-004 }}</ref>

==Habitat and ecology== left|thumb|In Taiwan The redbelly tilapia has a preference for shallow waters with vegetation,<ref name=fishbase/> but it also occurs in more open habitats like sandy shores and as deep as {{cvt|30|m|-2}}.<ref name="iucn status 20 November 2021" />

Although primarily a species of fresh and brackish water habitats, it tolerates high salinities, up to 4% (sea water is {{circa}} 3.5%), but the upper breeding limit is at 2.9%.<ref name=Gophen2018/> The redbelly tilapia also can live in a wide range of water temperatures, but in the northern part of its range it sometimes falls below its requirements (minimum {{cvt|6.5-13|C|F|disp=sqbr}}, depending on a range of factors), resulting in large numbers dying.<ref name=Gophen2018/> In Alabama, it was necessary to introduce them each year to maintain a population, as they die during the winter.<ref name=NASD/> The upper limit typically is {{cvt|36|C|F}}, but it can survive to {{cvt|42.5|C|F}}.<ref name=fishbase/>

==Appearance== The redbelly tilapia can reach up to {{cvt|300|g}} in weight and {{cvt|40|cm}} in length, but usually is no more than {{cvt|30|cm|0}}.<ref name=fishbase/> In the Middle East, adults typically are {{cvt|12-22|cm|0}} long.<ref name=Gophen2018/> Males tend to grow larger than females, but otherwise the sexes are similar.<ref name=Genner2018/> left|thumb|Young redbelly tilapia Its base color is brownish-olivaceous and the belly is yellowish or whitish. It often (for example, when agitated) has a faint/poorly defined dark pattern consisting of two horizontal lines on the body crossed by about half a dozen vertical bars. Breeding adults are more greenish overall, have iridescent blue-green spots on the head and bright pinkish-red underparts.<ref name=fishbase/><ref name=UCDavis>{{cite web | title=California Fish Website — Tilapia | url=http://calfish.ucdavis.edu/species/?ds=698&uid=22 | publisher=University of California | year=2019 | access-date=12 November 2019 }}</ref> This species very closely resembles the redbreast tilapia (''C. rendalli'') and the two are difficult to distinguish; many reports of introduced populations may involve either species.<ref name=Genner2018/><ref name=NASD/> The two have separate natural distribution (redbelly tilapia in the northern half of Africa, redbreast tilapia in the southern half), but through introductions their ranges now overlap. Whether they can hybridize is unknown.<ref name=Genner2018/> It has hybridized with the spotted tilapia (''Pelmatolapia mariae''),<ref name=Taylor1968>{{cite journal | author1=Taylor, J.N. | author2=D.B. Snyder | author3=W.R. Courtenay, Jr. | year=1986 | title=Hybridization between Two Introduced, Substrate-Spawning Tilapias (Pisces: Cichlidae) in Florida | journal=Copeia | volume=1986 | issue=4 | pages=903–909 | doi=10.2307/1445286 | jstor=1445286 }}</ref> a quite distant relative.<ref name=Dunz2013/>

==Behavior== As typical of ''Coptodon'', the redbelly tilapia is a substrate spawner and brooder. The "nest" typically is a small depression in the bottom that is dug by both parents,<ref name=Genner2018/><ref name=NASD/> but sometimes the eggs are placed on the top of a stone or the "nest" is an up to {{convert|85|cm|ftin|adj=mid|-deep}} tunnel that is dug into muddy substrate.<ref name=Gophen2018/> Several pairs may breed quite closely together forming a colony. Each female lays 1,000–6,000 eggs per spawning and she may spawn multiple times in a season.<ref name=UCDavis/> Both parents guard the eggs and fry.<ref name=Genner2018/><ref name=NASD/><ref name=Gophen2018/> In tropical locations it breeds year-round, although peaking in the rainy season.<ref name="iucn status 20 November 2021" /><ref name=NASD/> In colder subtropical regions like Israel it only breeds in the summer,<ref name=NASD/><ref name=Gophen2018/> at water temperatures of at least {{cvt|20|C|F}}.<ref name=UCDavis/> All other cichlids native to Western Asia are mouthbrooders.<ref name=Gophen2018/>

The redbelly tilapia mostly feeds on algae and higher plants (both aquatic plants and land plants that become accessible to the fish), but it also takes smaller quantities of invertebrates and fish eggs.<ref name=Genner2018/><ref name=NASD/> Young redbelly tilapias feed extensively on tiny crustaceans.<ref name=UCDavis/>

==References== {{Reflist}}

* https://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=169813

Redbelly tilapia Category:Taxa named by Paul Gervais Category:Fish described in 1848