Garra is a genus of fish in the family Cyprinidae. These fish are one example of the "log suckers", sucker-mouthed barbs and other cyprinids commonly kept in aquaria to keep down algae. The doctor fish of Anatolia and the Middle East belongs in this genus. The majority of the more than 160 species of garras are native to Asia, but about one-fifth of the species are from Africa (East, Middle and West, but by far the highest species richness in Ethiopia).
Description and ecology These species are slim cyprinids with a flat belly and a sucking mouth; their shape indicates that they are at least in tendency rheophilic. They are distinguished from other cyprinids by a combination of features: As in their closest relatives, their lower lip is expanded at its posterior rim to form a round or oval sucking pad, the vomero-palatine organ is much reduced or completely lost, the pectoral fins have at least the first two rays enlarged and usually unbranched, the supraethmoid is wider than long when seen from above, and the cleithrum is narrow and elongated to the front.
From other Garrini (or Garraina), the genus Garra can be distinguished as follows: their pharyngeal teeth are arranged in three rows (like 2,4,5–5,4,2), the dorsal fin has 10 or 11 rays and starts slightly anterior to the pelvic fins, while the anal fin starts well behind the pelvic fins and has 8 or 9 rays. As far as is known, the diploid karyotype of garras is 2n = 50.
Garras are not or barely noticeably sexually dimorphic and generally cryptically coloured benthic freshwater fish. Six species in the genus (G. andruzzii, G. dunsirei, G. lorestanensis, G. tashanensis, G. typhlops and some populations of G. barreimiae) are cave-adapted, lacking pigmentation and/or eyes. Garras are omnivorous, eating alga, plankton and small invertebrates that they suck off substrate like rocks or logs. The food is scraped off with the sharp keratinized borders of the jaws and ingested via suction, created by contracting and relaxing the buccopharynx. As typical for Cypriniformes, the garras lack a stomach entirely, their oesophagus leading directly to the sphincter of the intestine. Different Garra species eat animal and vegetable matter in different proportions, which can – as typical for vertebrates – usually be recognized by the length of their intestine compared to related species: more herbivorous species have a longer intestine. Indeed, intestinal length in this genus is remarkably constant within species and varies a lot between species, meaning that it is useful to distinguish species and that dietary shifts have played a significant role in the evolution of garras.
When the females are ready to spawn, they are markedly plump and swollen; the ripe roe may fill almost four-fifths of their body cavity. The testicles of reproductive males are large too. The average Garra egg is 1.77 mm in diameter and a clutch contains several hundred eggs – up to a thousand or so in large females. The breeding behaviour is generally not well known and breeding is not often achieved in the aquarium; presumably, like many of their relatives they migrate upstream or (if they otherwise inhabit lakes) into the rivers to spawn.
Taxonomy The genus was established by Francis Buchanan-Hamilton in 1822 as a subgenus of Cyprinus (which at that time was a "basket genus" for carp-like cyprinids); he did not designate a type species, though as the only member of this subgenus was Garra lamta it became the type species of the genus after Pieter Bleeker did a taxonomic revision in 1863. The garras and their closest relatives are sometimes placed in a subfamily Garrinae, but this seems hardly warranted. More often, this group is included in the Labeoninae, or together with these in the Cyprininae. In the former case, the garras are members of the labeonine tribe Garrini, in the latter they are in the subtribe Garraina of tribe Labeonini. The genus Discogobio was considered a close relative, but this is no longer thought to be the case.
Phylogeny The following maximum likelihood phylogenetic tree is based on a dataset of nuclear and mitochondrial DNA, from Yang et al. 2012, with updated binomial names:
"Garra" imberba and "G." micropulvinus were recovered in a more derived position than Garra sensu stricto; the two were recovered within the same clade as Discogobio and Pseudocrossocheilus, so they were subsequently reassigned to new genera.
Species These are the currently recognized species in this genus:
Garra abhoyai Hora, 1921 Garra aethiopica (Pellegrin, 1927) Garra allostoma T. R. Roberts, 1990 Garra alticaputus Arunachalam, Nandagopal & Mayden, 2013 Garra alticauda L. Cao, Nyingi, Bart & E. Zhang, 2023 Garra amirhosseini Esmaeili, Sayyadzadeh, Coad & Eagderi, 2016 Garra andruzzii (Vinciguerra, 1924) (Somalian cavefish) Garra annandalei Hora, 1921 Garra apogon (Norman, 1925) Garra arunachalami J. J. Johnson & R. Soranam, 2001 Garra arunachalensis Nebeshwar & Vishwanath, 2013 Garra arupi Nebeshwar, Vishwanath & D. N. Das, 2009 Garra barreimiae Fowler & Steinitz, 1956 Garra bicornuta Narayan Rao, 1920 Garra biloborostris Roni & Vishwanath, 2017 Garra bimaculacauda Thoni, Gurung & Mayden, 2016 Garra binduensis U. Das, Kosygin & Panigrahi, 2016 Garra birostris Nebeshwar & Vishwanath, 2013 Garra bispinosa E. Zhang, 2005 Garra blanfordii (Boulenger, 1901) Garra borneensis (Vaillant, 1902) Garra bourreti (Pellegrin, 1928) Garra buettikeri Krupp, 1983 Garra caudomaculata (Battalgil, 1942) (Antakya minnow) Garra centrala V. H. Nguyễn, T.H.N. Vũ & T.D.P. Nguyễn, 2015 Garra ceylonensis Bleeker, 1863 (Ceylon logsucker) Garra chakpiensis Nebeshwar & Vishwanath, 2015 Garra chathensis Ezung, Shangningam & Pankaj, 2020 Garra chaudhurii Hora, 1921 Garra chebera Habteselassie, Mikschi, Ahnelt & Waidbacher, 2010 Garra chindwinensis Premananda, Kosygin, Saidullah, 2017 Garra chingaiensis Abonmai, Linthoingambi, Ngangbam, Thoidingjam & K. R. Singh, 2023 Garra chivaensis Moyon & L. Arunkumar, 2020 Garra clavirostris Roni, Sarbojit & Vishwanath, 2017 Garra compressa Kosygin & Vishwanath, 1998 Garra congoensis Poll, 1959 Garra cornigera Shangningam & Vishwanath, 2015 Garra culiciphaga (Pellegrin, 1927) (Redstripe barb) Garra cyclostomata Đ. Y. Mai, 1978 Garra cyrano Kottelat, 2000 Garra dampaensis Lalronunga, Lalnuntluanga & Lalramliana, 2013 Garra deccanensis Jadhav, Karuthapandi, Shangningam, Jaiswal & Shankar, 2022 Garra dembecha Getahun & Stiassny, 2007 Garra dembeensis (Rüppell, 1835) (Dembea stone lapper) Garra dengba S.-Q. Deng, L. Cao & E. Zhang, 2018 Garra dohjei Marngar, Mawlong & Lokeshwor, 2024 Garra dulongensis (Chen, X. F. Pan, X. Hong & J. X. Yang, 2006) Garra dunsirei Banister, 1987 Garra duobarbis Getahun & Stiassny, 2007 Garra elegans (Günther, 1868) Garra elongata Vishwanath & Kosygin, 2000 Garra emarginata Kurup & Radhakrishnan, 2011 Garra ethelwynnae Menon, 1958 Garra festai (Tortonese, 1939) Garra flavatra S. O. Kullander & F. Fang, 2004 Garra fluviatilis Kangrang, Thoni, Mayden & Beamish, 2016 Garra fuliginosa Fowler, 1934 Garra gallagheri Krupp, 1988 (Black Garra) Garra geba Getahun & Stiassny, 2007 Garra ghorensis Krupp, 1982 Garra gotyla (J. E. Gray, 1830) (Sucker head) Garra gracilis (Pellegrin & Chevey, 1936) Garra gravelyi (Annandale, 1919) Garra gymnothorax Berg, 1949 (Chest scaleless garra) Garra hexagonarostris Nebeshwar, Rameshori & Prabina, 2024 Garra hindii (Boulenger, 1905) Garra hormuzensis Zamani-Faradonbe, E. Zhang & Keivany, 2021 Garra hughi Silas, 1955 Garra ignestii (Gianferrari, 1925) Garra imberbis (Vinciguerra, 1890) Garra irangensis Premananda, 2023 Garra jaldhakaensis Kosygin, Shangningam, Singh & U. Das, 2021 Garra jamila Moritz, Straube & Neumann, 2019 Garra jenkinsonianum Hora, 1921 Garra jerdoni F. Day, 1867 Garra jordanica Hamidan, Geiger & Freyhof, 2014 Garra joshuai (Silas, 1954) Garra kalakadensis Rema Devi, 1993 Garra kalpangi Nebeshwar, Bagra & D. N. Das, 2012 Garra kangrae Prashad, 1919 Garra kemali (Hankó, 1925) (Eregil minnow) Garra kempi Hora, 1921 Garra khawbungi Arunachalam, Nandagopal & Mayden, 2014 Garra kimini Arunachalam, Nandagopal & Mayden, 2014 Garra klatti (Kosswig, 1950) Garra koladynensis Nebeshwar & Vishwanath, 2017 Garra laishrami Surachita, Chowdhury & Palita, 2023 Garra lamta (F. Hamilton, 1822) Garra lancrenonensis Blache & Miton, 1960 Garra langlungensis Ezung, Shangningam & Pankaj, 2021 Garra lautior Banister, 1987 Garra lissorhynchus (McClelland, 1842) Garra litanensis Vishwanath, 1993 Garra longchuanensis Q. Yu, X. Z. Wang, H. Xiong & S. P. He, 2016 Garra longipinnis Banister & M. A. Clarke, 1977 Garra lorestanensis Mousavi-Sabet & Eagderi, 2016 Garra lungongza Ngangbam & Lithoingambi, 2023 Garra magnacavus Shangningam, Kosygin & Sinha, 2019 Garra magnidiscus Tamang, 2013 Garra makiensis (Boulenger, 1904) Garra mamshuqa Krupp, 1983 Garra manipurensis Vishwanath & Sarojnalini, 1988 Garra matensis Nebeshwar & Vishwanath, 2017 Garra mcclellandi (Jerdon, 1849) Garra menderesensis (Küçük, Bayçelebi, Güçlü & Gülle, 2015) Garra menoni Rema Devi & T. J. Indra, 1984 Garra meymehensis Zamani-Faradonbe, Keivany, Dorafshan & E. Zhang, 2021 Garra mini Rahman, Mollah, Norén & S. O. Kullander, 2016 Garra minibarbata L. Cao, Nyingi, Bart & E. Zhang 2023 Garra minimus Arunachalam, Nandagopal & Mayden, 2013 Garra mirofrontis X. L. Chu & G. H. Cui, 1987 Garra mlapparaensis Kurup & Radhakrishnan, 2011 Garra mondica Sayyadzadeh, Esmaeili & Freyhof, 2015 Garra montisalsi Hora, 1921 Garra motuoensis Z. Gong, Freyhof, J. Wang, M. Liu, F. Liu, P. C. Lin, Y. Jiang & H. Z. Liu 2018 Garra moyonkhulleni Moyon & Arunkumar, 2018 Garra mullya (Sykes, 1839) (sucker fish) Garra naganensis Hora, 1921 Garra nambulica Vishwanath & Joyshree, 2005r. Garra namyaensis Shangningam & Vishwanath, 2012 Garra nana (Heckel, 1843) Garra napata Moritz, Straube & Neumann, 2019 Garra nasuta (McClelland, 1838) Garra nepalensis Rayamajhi & Arunachalam, 2017 Garra nethravathiensis Arunachalam & Nandagopal, 2014 Garra ngatangkha Arunkumar & Moyon, 2019 Garra ngopi Tenali, Chandran, R. K. Singh & Sarkar, 2024 Garra nigricauda Arunachalam, Nandagopal & Mayden, 2013 Garra nigricollis S. O. Kullander & F. Fang, 2004 Garra notata (Blyth, 1860) Garra nudiventris (Berg, 1905) Garra orientalis Nichols, 1925 Garra ornata (Nichols & Griscom, 1917) Garra orontesi Bayçelebi, Kaya, Turan & Freyhof, 2021 Garra palaniensis (Rema Devi & Menon, 1994) Garra palaruvica Arunachalam, Raja, Nandagopal & Mayden, 2013 Garra panitvongi Tangjitjaroen, Z. S. Randall, Tongnunui, Boyd & Page, 2023 Garra paralissorhynchus Vishwanath & K. Shanta Devi, 2005 Garra parastenorhynchus Thoni, Gurung & Mayden, 2016 Garra paratrilobata Roni, Chinglemba, Rameshori & Vishwanath, 2019 Garra periyarensis K. C. Gopi, 2001 Garra persica Berg, 1914 Garra phewakholaensis Limbu, Rajbanshi & Raza 2024 Garra phillipsi Deraniyagala, 1933 (Phillips's garra) Garra platycephala Narayan Rao, 1920 Garra poecilura S. O. Kullander & F. Fang 2004 Garra poilanei Petit & T. L. Tchang, 1933 Garra prashadi Hora, 1921 Garra propulvinus S. O. Kullander & F. Fang 2004 Garra qiaojiensis H. W. Wu & Yao, 1977 Garra quadratirostris Nebeshwar & Vishwanath, 2013 Garra quadrimaculata (Rüppell 1835) Garra quangtriensis V. H. Nguyễn, T.H.N. Vũ & T. D. P. Nguyễn, 2015 Garra rakhinica S. O. Kullander & F. Fang 2004 Garra ranganensis Tamang, Sinha, Abujam & Kumar, 2019 Garra regressa Getahun & Stiassny, 2007 Garra rezai Mousavi-Sabet, Eagderi, Saemi-Komsari, Kaya & Freyhof, 2022 Garra rhynchota Koller, 1926 Garra robertsi Thoni & Mayden, 2015 Garra roseae Mousavi-Sabet, Saemi-Komsari, Doadrio & Freyhof, 2019 Garra rossica (A. M. Nikolskii, 1900) Garra rotundinasus E. Zhang, 2006 Garra rufa (Heckel, 1843) (Red garra) Garra rupecula (McClelland, 1839)