''Atlantirivulus'' 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 ...

of fishes in the

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Rivulidae The Rivulidae are a family of killifishes in the order Cyprinodontiformes. They are commonly known as rivulids, South American killifish or New World killifish. The latter names are slightly misleading, however, as they are neither restricted to ...

. They are

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

to shallow swamps, creeks, streams and pools in the

Atlantic Forest The Atlantic Forest ( pt, Mata Atlântica) is a South American forest that extends along the Atlantic coast of Brazil from Rio Grande do Norte state in the northeast to Rio Grande do Sul state in the south and inland as far as Paraguay and th ...

in southeastern

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 ...

, ranging from

Rio de Janeiro Rio de Janeiro ( , , ; literally 'River of January'), or simply Rio, is the capital of the state of the same name, Brazil's third-most populous state, and the second-most populous city in Brazil, after São Paulo. Listed by the GaWC as a b ...

to Santa Catarina.Costa, W.J.E.M. (2014)
Four new species of the genus ''Atlantirivulus'' (Cyprinodontiformes: Rivulidae) from the Brazilian Atlantic Forest.
''Vertebrate Zoology, 64 (1): 9–21.'' Several of the species are highly threatened, while others survive in well-protected reserves. ''A. janeiroensis'' was initially feared extinct, but has since been rediscovered in two reserves. Similar to closely related genera such as ''

Anablepsoides ''Anablepsoides'' is a genus of killifish in the family Rivulidae native to tropical South America and the Lesser Antilles. The majority are from the Amazon and Orinoco basins, as well as freshwater systems in the Guiana Shield, but a few species ...

'', ''

Cynodonichthys ''Cynodonichthys'' is a genus of freshwater killifish in the family Rivulidae. They are found in Middle America, ranging from southern Mexico (north to Oaxaca and the Yucatán Peninsula), through Central America (where most species live), to Col ...

'', ''

Laimosemion ''Laimosemion'' is a genus of fish in the family Rivulidae from the Amazon basin and basins in the Guiana Shield in tropical South America. They mostly inhabit small streams, creeks, swamps and pools in lowlands, but locally occur to an altitude ...

'' and ''

Melanorivulus ''Melanorivulus'' is a genus of South American freshwater fish in the family Rivulidae. Most species are endemic to the Río de la Plata, eastern Amazon (west to Tapajós basin), Tocantins– Araguaia and São Francisco basins in Brazil, but a f ...

'', ''Atlantirivulus'' are non-annual

killifish A killifish is any of various oviparous (egg-laying) cyprinodontiform fish (including families Aplocheilidae, Cyprinodontidae, Fundulidae, Profundulidae and Valenciidae). All together, there are 1,270 species of killifish, the biggest family ...

. They are small fish, no more than in

total length Fish measurement is the measuring of individual fish and various parts of their anatomies. These data are used in many areas of ichthyology, including taxonomy and fisheries biology. Overall length * Standard length (SL) is the length of a fish ...

. Compared to many species in the family, the colors of ''Atlantirivulus'' are relatively dull.

Species

Until 2011, ''Atlantirivulus'' were included in ''

Rivulus ''Rivulus'' is a genus of small freshwater fish in the Cyprinodontiformes family Rivulidae. It was traditionally considered to be the largest genus in its family; however, the genus's size is currently in dispute. Wilson J. E. Costa split this ge ...

Köhler Köhler is a German surname, referring to a man making charcoal from wood. Geographical distribution As of 2014, 96.2% of all known bearers of the surname ''Köhler'' were residents of Germany (frequency 1:641) and 1.5% of Austria (1:4,238). ...

, 1906 * '' Atlantirivulus simplicis'' W. J. E. M. Costa, 2004 * '' Atlantirivulus unaensis'' W. J. E. M. Costa & De Luca, 2009

References

Rivulidae Freshwater fish genera {{Cyprinodontiformes-stub