''Ochmacanthus'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

pencil catfish Trichomycteridae is a family of catfishes commonly known as pencil catfishes or parasitic catfishes. This family includes the candiru fish (''Vandellia cirrhosa''), feared by some people for its alleged habit of entering into the urethra of hum ...

es native to

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southe ...

. These

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 appropriate s ...

are distributed in

. ''O. alternus'' and ''O. orinoco'' originate from the Rio Negro and

Orinoco River The Orinoco () is one of the longest rivers in South America at . Its drainage basin, sometimes known as the Orinoquia, covers , with 76.3 percent of it in Venezuela and the remainder in Colombia. It is the fourth largest river in the wor ...

basins of

Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...

and

Venezuela Venezuela (; ), officially the Bolivarian Republic of Venezuela ( es, link=no, República Bolivariana de Venezuela), is a country on the northern coast of South America, consisting of a continental landmass and many islands and islets in th ...

. ''O. batrachstoma'' inhabits the

Paraguay River The Paraguay River (Río Paraguay in Spanish, Rio Paraguai in Portuguese, Ysyry Paraguái in Guarani) is a major river in south-central South America, running through Brazil, Bolivia, Paraguay and Argentina. It flows about from its headwaters in ...

basin in Brazil. ''O. flabelliferus'' lives in river drainages in

Guyana Guyana ( or ), officially the Cooperative Republic of Guyana, is a country on the northern mainland of South America. Guyana is an indigenous word which means "Land of Many Waters". The capital city is Georgetown. Guyana is bordered by the ...

and Venezuela. ''O. reinhardtii'' is known from the

Amazon River The Amazon River (, ; es, Río Amazonas, pt, Rio Amazonas) in South America is the largest river by discharge volume of water in the world, and the disputed longest river system in the world in comparison to the Nile. The headwaters of t ...

basin in Brazil and drainages in

French Guiana French Guiana ( or ; french: link=no, Guyane ; gcr, label=French Guianese Creole, Lagwiyann ) is an overseas departments and regions of France, overseas department/region and single territorial collectivity of France on the northern Atlantic ...

Species

There are currently 5 recognized species in this genus: * ''

Ochmacanthus alternus ''Ochmacanthus'' is a genus of pencil catfishes native to South America. These species are distributed in South America. ''O. alternus'' and ''O. orinoco'' originate from the Rio Negro and Orinoco River basins of Brazil and Venezuela. ''O. batra ...

'' G. S. Myers, 1927 * ''

Ochmacanthus batrachostoma ''Ochmacanthus'' is a genus of pencil catfishes native to South America. These species are distributed in South America. ''O. alternus'' and ''O. orinoco'' originate from the Rio Negro and Orinoco River basins of Brazil and Venezuela. ''O. batra ...

'' ( A. Miranda-Ribeiro, 1912) Neto, C.S. & de Pinna, M. (2016): Redescription of ''Ochmacanthus batrachostoma'' (Miranda-Ribeiro, 1912) (Siluriformes: Trichomycteridae): a possible case of incipient paedomorphism. ''Neotropical Ichthyology, 14 (1): e150030.'' * ''

Ochmacanthus flabelliferus ''Ochmacanthus'' is a genus of pencil catfishes native to South America. These species are distributed in South America. ''O. alternus'' and ''O. orinoco'' originate from the Rio Negro and Orinoco River basins of Brazil and Venezuela. ''O. batra ...

Eigenmann Eigenmann is a surname. Notable persons with that surname include: * Andi Eigenmann (born 1990), Filipino actress * Carl H. Eigenmann (1863–1927), German–American ichthyologist, husband of Rosa Eigenmann * Eduardo de Mesa Eigenmann, birth name ...

, 1912 * ''

Ochmacanthus orinoco ''Ochmacanthus'' is a genus of pencil catfishes native to South America. These species are distributed in South America. ''O. alternus'' and ''O. orinoco'' originate from the Rio Negro and Orinoco River basins of Brazil and Venezuela. ''O. batra ...

'' G. S. Myers, 1927 * ''

Ochmacanthus reinhardtii ''Ochmacanthus'' is a genus of pencil catfishes native to South America. These species are distributed in South America. ''O. alternus'' and ''O. orinoco'' originate from the Rio Negro and Orinoco River basins of Brazil and Venezuela. ''O. batra ...

'' (

Steindachner Franz Steindachner (11 November 1834 in Vienna – 10 December 1919 in Vienna) was an Austrian zoologist, ichthyologist, and herpetologist. He published over 200 papers on fishes and over 50 papers on reptiles and amphibians. Steindachner describ ...

, 1882)

References

Trichomycteridae Fish of South America Fish of the Amazon basin Fish of Brazil Fish of French Guiana Fish of Guyana Fish of Venezuela Freshwater fish genera Catfish genera Taxa named by Carl H. Eigenmann {{Trichomycteridae-stub