# Trichomycterus

Trichomycterus is a genus of fish in the family Trichomycteridae, the largest genus of its family with over 170 species currently described. This genus is native to freshwater habitats in Central and South America. These fish are generally small, usually about 5 to 15 cm (2–6 in) in standard length, although the largest, T. rivulatus, can reach more than twice this size. Species differ from one another primarily in body proportions, fin ray counts and colouration. Despite their relatively small size, some, such as T. punctulatus, support fisheries and are important in the local cuisine.

## Taxonomy

This genus is defined by the lack of specializations found in other trichomycterids and is certainly polyphyletic. Although known to contain many species, Trichomycterus is poorly known with many of the known species based on brief descriptions. Many species have been described recently and many more are waiting to be described.
Some authors have tentatively defined putative monophyletic assemblages within the genus Trichomycterus based on the possession of unique morphological features. The Trichomycterus brasiliensis species-complex includes T. brasiliensis, T. iheringi, T. maracaya, T. mimonha, T. pirabitira, T. potschi, T. vermiculatus and several undescribed species apparently endemic to the main river basins draining the Brazilian Shield. However, an assemblage of species from south and southeastern Brazil is also supported that includes T. araxa, T. castroi, T. davisi, T. guaraquessaba, T. immaculatus, T. itatiayae, T. mboycy, T. mirissumba, T. naipi, T. nigricans, T. papilliferus, T. plumbeus, T. stawiarski, T. taroba, T. triguttatus and T. zonatus, T. aguarague, T. alterus, T. belensis, T. boylei and T. ramosus also form a diagnosable species assemblage.

## Distribution and habitat

Species of Trichomycterus inhabit a diversity of habitats throughout South and Central America from Costa Rica in the north to Patagonia in the south and from lowland Atlantic rainforest in the east to Andean highland streams in the west. They are, together with Astroblepus and Orestias, among the very few native fish genera at high altitude in the Andes and in some places, for example certain high-elevation localities in western Argentina, Trichomycterus are the only fishes. About 60 nominal species are endemic to the river basins draining the Andes and hills of the Guianan Shield and about 30 species are endemic to river basins draining the Brazilian Shield.
Despite the broad distribution of the genus, most species have limited distributions and usually are restricted to only one river. Wide-ranging species are most likely complexes of species that are difficult to differentiate, such as the T. brasiliensis species-complex. Trichomycterus gorgona, from a small stream on Gorgona Island located west of the Pacific coast of Colombia, is the first known trichomycterid to be endemic to an offshore island. Many species are troglobitic.

## Species

There are currently 174 recognized species in this genus:
| Trichomycterus aguarague L. A. Fernández & Osinaga, 2006 Trichomycterus albinotatus W. J. E. M. Costa, 1992 Trichomycterus alternatus (C. H. Eigenmann, 1917) Trichomycterus alterus (Marini, Nichols & La Monte, 1933) Trichomycterus anhanga Dutra, Wosiacki & de Pinna, 2012 Trichomycterus araxa W. J. E. M. Costa, Mattos, Sampaio, Giongo, Almeida, & Katz, 2022 Trichomycterus areolatus Valenciennes, 1846 Trichomycterus argos Lezama, Triques & P. S. Santos, 2012 Trichomycterus arhuaco Ardila Rodríguez, 2016 Trichomycterus arleoi (Fernández-Yépez, 1972) Trichomycterus atochae (W. R. Allen, 1942) Trichomycterus auroguttatus W. J. E. M. Costa, 1992 Trichomycterus bahianus W. J. E. M. Costa, 1992 Trichomycterus balios Ferrer & L. R. Malabarba, 2013 Trichomycterus ballesterosi Ardila Rodríguez, 2011 Trichomycterus banneaui (C. H. Eigenmann, 1912) Trichomycterus barbouri (C. H. Eigenmann, 1911) Trichomycterus belensis L. A. Fernández & Vari, 2002 Trichomycterus berthalutzae Costa, Barbosa & Katz 2024 Trichomycterus bogotensis (C. H. Eigenmann, 1912) Trichomycterus bomboizanus (Tortonese, 1942) Trichomycterus borellii Boulenger, 1897 Trichomycterus boylei (Nichols, 1956) Trichomycterus brachykechenos Ferrer & L. R. Malabarba, 2013 Trichomycterus brasiliensis Lütken, 1874 Trichomycterus brunoi M. A. Barbosa & W. J. E. M. Costa, 2010 Trichomycterus cachiraensis Ardila Rodríguez, 2008 Trichomycterus caipora S. M. Q. Lima, Lazzarotto & W. J. E. M. Costa, 2008 Trichomycterus caliensis (C. H. Eigenmann, 1912) Trichomycterus candidus (P. Miranda-Ribeiro, 1949) Trichomycterus caribensis Ardila Rodríguez 2024 Trichomycterus casitaensis Ardila Rodríguez, 2017 Trichomycterus castroi de Pinna, 1992 Trichomycterus catamarcensis L. A. Fernández & Vari, 2000 Trichomycterus caudofasciatus Alencar & W. J. E. M. Costa, 2004 Trichomycterus celsae Lasso A. & Provenzano, 2003 Trichomycterus chaberti Durand, 1968 Trichomycterus chapmani (C. H. Eigenmann, 1912) Trichomycterus chiltoni (C. H. Eigenmann, 1920) Trichomycterus choroloensis Trichomycterus chungaraensis Arratia, 1983 Trichomycterus claudiae M. A. Barbosa & W. J. E. M. Costa, 2010 Trichomycterus concolor W. J. E. M. Costa, 1992 Trichomycterus conradi (C. H. Eigenmann, 1912) Trichomycterus corduvensis Weyenbergh (de), 1877 Trichomycterus crassicaudatus Wosiacki & de Pinna, 2008 Trichomycterus cubataonis Bizerril, 1994 Trichomycterus dali Rizzato, E. P. D. Costa, Trajano & Bichuette, 2011 Trichomycterus davisi (Haseman, 1911) Trichomycterus diabolus Bockmann, Casatti & de Pinna, 2004 Trichomycterus diatropoporos Ferrer & L. R. Malabarba, 2013 Trichomycterus dispar (Tschudi, 1846) Trichomycterus dorsostriatus (C. H. Eigenmann, 1917) Trichomycterus duellmani Arratia & Menu-Marque, 1984 Trichomycterus emanueli (L. P. Schultz, 1944) Trichomycterus fabioheppi Costa, Barbosa & Katz 2024 Trichomycterus fassli (Steindachner, 1915) Trichomycterus florensis (P. Miranda-Ribeiro, 1943) Trichomycterus fuliginosus M. A. Barbosa & W. J. E. M. Costa, 2010 Trichomycterus gabrieli (G. S. Myers, 1926) Trichomycterus galvisi Trichomycterus garciamarquezi Ardila Rodríguez, 2016 Trichomycterus gasparinii M. A. Barbosa, 2013 Trichomycterus giarettai M. A. Barbosa & Katz, 2016 Trichomycterus giganteus S. M. Q. Lima & W. J. E. M. Costa, 2004 Trichomycterus goeldii Boulenger, 1896 Trichomycterus gorgona L. A. Fernández & Schaefer, 2005 Trichomycterus guaraquessaba Wosiacki, 2005 Trichomycterus guianensis (C. H. Eigenmann, 1909) Trichomycterus hasemani (C. H. Eigenmann, 1914) Trichomycterus heterodontus (C. H. Eigenmann, 1917) Trichomycterus hualco L. A. Fernández & Vari, 2009 Trichomycterus igobi Wosiacki & de Pinna, 2008 Trichomycterus iheringi (C. H. Eigenmann, 1917) Trichomycterus immaculatus (C. H. Eigenmann & R. S. Eigenmann, 1889) Trichomycterus itacambirussu Triques & Vono, 2004 Trichomycterus itacarambiensis Trajano & de Pinna, 1996 Trichomycterus itatiayae A. Miranda-Ribeiro, 1906 Trichomycterus jacupiranga Wosiacki & Oyakawa, 2005 Trichomycterus jequitinhonhae Triques & Vono, 2004 Trichomycterus johnsoni (Fowler, 1932) Trichomycterus kankuamo Ardila Rodríguez, 2016 Trichomycterus knerii Steindachner, 1882 Trichomycterus landinga Triques & Vono, 2004 Trichomycterus latidens (C. H. Eigenmann, 1917) Trichomycterus latistriatus (C. H. Eigenmann, 1917) Trichomycterus laucaensis Arratia, 1983 Trichomycterus lauryi Donin, Ferrer & Carvalho, 2020 Trichomycterus lewi Lasso A. & Provenzano, 2003 Trichomycterus longibarbatus W. J. E. M. Costa, 1992 Trichomycterus macareguaensis Trichomycterus macrophthalmus M. A. Barbosa & W. J. E. M. Costa, 2012 Trichomycterus macrotrichopterus M. A. Barbosa & W. J. E. M. Costa, 2010 Trichomycterus maculosus M. A. Barbosa & W. J. E. M. Costa, 2010 Trichomycterus maldonadoi Ardila Rodríguez, 2011 Trichomycterus manaurensis Ardila Rodríguez, 2016 Trichomycterus maracaiboensis (L. P. Schultz, 1944) Trichomycterus maracaya Bockmann & Sázima (fr), 2004 | Trichomycterus mariamole M. A. Barbosa & W. J. E. M. Costa, 2010 Trichomycterus mboycy Wosiacki & Garavello, 2004 Trichomycterus megantoni L. A. Fernández & Chuquihuamaní, 2007 Trichomycterus meridae Regan, 1903 Trichomycterus migrans (Dahl, 1960) Trichomycterus mimonha W. J. E. M. Costa, 1992 Trichomycterus mimosensis M. A. Barbosa, 2013 Trichomycterus minus L. A. Fernández & Vari, 2012 Trichomycterus mirissumba W. J. E. M. Costa, 1992 Trichomycterus mondolfi (L. P. Schultz, 1945) Trichomycterus montesi Ardila Rodríguez, 2016 Trichomycterus motatanensis (L. P. Schultz, 1944) Trichomycterus naipi Wosiacki & Garavello, 2004 Trichomycterus nietoi Ardila Rodríguez, 2014 Trichomycterus nigricans Valenciennes, 1832 Trichomycterus nigroauratus M. A. Barbosa & W. J. E. M. Costa, 2008 Trichomycterus nigromaculatus Boulenger, 1887 Trichomycterus novalimensis M. A. Barbosa & W. J. E. M. Costa, 2010 Trichomycterus ocanaensis Ardila Rodríguez, 2011 Trichomycterus oroyae (C. H. Eigenmann & R. S. Eigenmann, 1889) Trichomycterus pantherinus Alencar & W. J. E. M. Costa, 2004 Trichomycterus paolence (C. H. Eigenmann, 1917) Trichomycterus papilliferus Wosiacki & Garavello, 2004 Trichomycterus paquequerensis (P. Miranda-Ribeiro, 1943) Trichomycterus pascuali Ochoa, G. S. C. Silva, G. J. C. Silva, C. de Oliveira & Datovo, 2017 Trichomycterus pauciradiatus Alencar & W. J. E. M. Costa, 2006 Trichomycterus payaya Sarmento-Soares, Zanata & Martins-Pinheiro, 2011 Trichomycterus perkos Datovo, M. de Carvalho & Ferrer, 2012 Trichomycterus pirabitira M. A. Barbosa & Azevedo-Santos, 2012 Trichomycterus piratymbara Katz, M. A. Barbosa & W. J. E. M. Costa, 2013 Trichomycterus piurae (C. H. Eigenmann, 1922) Trichomycterus plumbeus Wosiacki & Garavello, 2004 Trichomycterus poikilos Ferrer & L. R. Malabarba, 2013 Trichomycterus potschi M. A. Barbosa & W. J. E. M. Costa, 2003 Trichomycterus pradensis Sarmento-Soares, Martins-Pinheiro, Aranda & Chamon, 2005 Trichomycterus pseudosilvinichthys L. A. Fernández & Vari, 2004 Trichomycterus punctatissimus Castelnau, 1855 Trichomycterus punctulatus Valenciennes, 1846 Trichomycterus puriventris M. A. Barbosa & W. J. E. M. Costa, 2012 Trichomycterus quechuorus (Steindachner, 1900) Trichomycterus ramosus L. A. Fernández, 2000 Trichomycterus regani (C. H. Eigenmann, 1917) Trichomycterus reinhardti (C. H. Eigenmann, 1917) Trichomycterus retropinnis Regan, 1903 Trichomycterus riojanus (C. Berg, 1897) Trichomycterus rivulatus Valenciennes, 1846 Trichomycterus roigi Arratia & Menu-Marque, 1984 Trichomycterus romeroi (Fowler, 1941) Trichomycterus rubbioli Bichuette & Rizzato, 2012 Trichomycterus rubiginosus M. A. Barbosa & W. J. E. M. Costa, 2010 Trichomycterus ruitoquensis Ardila Rodríguez, 2007 Trichomycterus sandovali Ardila Rodríguez, 2006 Trichomycterus santaeritae (C. H. Eigenmann, 1918) Trichomycterus santanderensis Castellanos-Morales, 2007 Trichomycterus santuarioensis Trichomycterus septemradiatus Katz, M. A. Barbosa & W. J. E. M. Costa, 2013 Trichomycterus simacotaensis Trichomycterus sketi Castellanos-Morales, 2011 Trichomycterus spegazzinii (C. Berg, 1897) Trichomycterus spelaeus DoNascimiento, Villarreal & Provenzano, 2001 Trichomycterus spilosoma (Regan, 1913) Trichomycterus stawiarski (P. Miranda-Ribeiro, 1968) Trichomycterus steindachneri DoNascimiento, Prada-Pedreros & Guerrero-Kommritz, 2014 Trichomycterus stellatus (C. H. Eigenmann, 1918) Trichomycterus straminius (C. H. Eigenmann, 1917) Trichomycterus striatus (Meek & Hildebrand, 1913) Trichomycterus taczanowskii Steindachner, 1882 Trichomycterus taenia Kner, 1863 Trichomycterus taeniops Fowler, 1954 Trichomycterus taroba Wosiacki & Garavello, 2004 Trichomycterus tenuis Weyenbergh (de), 1877 Trichomycterus tete M. A. Barbosa & W. J. E. M. Costa, 2011 Trichomycterus tetuanensis L. J. García-Melo, Villa-Navarro & DoNascimiento, 2016 Trichomycterus therma L. A. Fernández & Miranda-Chumacero, 2007 Trichomycterus tiraquae (Fowler, 1940) Trichomycterus torcoromaensis Ardila Rodríguez, 2016 Trichomycterus transandianus (Steindachner, 1915) Trichomycterus trefauti Wosiacki, 2004 Trichomycterus triguttatus (C. H. Eigenmann, 1918) Trichomycterus tropeiro Ferrer & L. R. Malabarba, 2011 Trichomycterus tupinamba Wosiacki & Oyakawa, 2005 Trichomycterus uisae Castellanos-Morales, 2008 Trichomycterus unicolor (Regan, 1913) Trichomycterus variegatus W. J. E. M. Costa, 1992 Trichomycterus vermiculatus (C. H. Eigenmann, 1917) Trichomycterus vitalbrazili Paulo J. Vilardo, Katz & W. J. E. M. Costa Trichomycterus vittatus Regan, 1903 Trichomycterus wapixana Henschel, 2016 Trichomycterus weyrauchi (Fowler, 1945) Trichomycterus ytororo Terán, Ferrer, Benítez, F. Alonso, G. Aguilera & Mirande, 2017 Trichomycterus yuska L. A. Fernández & Schaefer, 2003 Trichomycterus zonatus (C. H. Eigenmann, 1918) |