The Rivulidae are a

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

killifish A killifish is any of various oviparous (egg-laying) cyprinodontiform fish, including families Aplocheilidae, Pantanodontidae, Cyprinodontidae, Fundulidae, Nothobranchiidae, Profundulidae, Aphaniidae and Valenciidae. All together, there ar ...

es in the

order Order, ORDER or Orders may refer to: * A socio-political or established or existing order, e.g. World order, Ancien Regime, Pax Britannica * Categorization, the process in which ideas and objects are recognized, differentiated, and understood ...

Cyprinodontiformes Cyprinodontiformes is an order (biology), order of Actinopterygii, ray-finned fish, comprising mostly small, freshwater fish. Many popular aquarium fish, such as killifish and Poeciliidae, live-bearers, are included. They are closely related t ...

. 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

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o ...

, though most are in fact found there, nor are they the only killifishes from the

Americas The Americas, sometimes collectively called America, are a landmass comprising the totality of North America and South America.''Webster's New World College Dictionary'', 2010 by Wiley Publishing, Inc., Cleveland, Ohio. When viewed as a sing ...

. Occasionally, they are still referred to as rivulines, a term dating back to when they were considered a

subfamily In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end botanical subfamily names with "-oideae", and zo ...

of the Aplocheilidae. The subfamilial name "Rivulinae" was already established for

noctuid moth The Noctuidae, commonly known as owlet moths, cutworms or armyworms, are a family of moths. Taxonomically, they are considered the most controversial family in the superfamily Noctuoidea because many of the clades are constantly changing, along w ...

s by

Augustus Radcliffe Grote Augustus Radcliffe Grote (February 7, 1841 – September 12, 1903) was a British entomologist who Species description, described over 1,000 species of Lepidoptera, butterflies and moths.Osborn, H. 1937. Fragments of Entomological History. Columb ...

in 1895. That name, though it is the

senior homonym In biology, a homonym is a name for a taxon that is identical in spelling to another such name, that belongs to a different taxon. The rule in the International Code of Zoological Nomenclature is that the first such name to be published is the s ...

, may be suppressed because the name Rivulinae for the fish subfamily is widespread, whereas the moth taxon is little used. The use of Rivulidae as the name for this family may need to be ruled in by the

International Commission on Zoological Nomenclature The International Commission on Zoological Nomenclature (ICZN) is an organization dedicated to "achieving stability and sense in the scientific naming of animals". Founded in 1895, it currently comprises 26 commissioners from 20 countries. Orga ...

. The alternative family-group name Cynolebiidae Hoedeman 1961 has been proposed as an alternative to Rivulidae. Costa unified the three families within the suborder

Aplocheiloidei Aplocheiloidei is a suborder of the Order (biology), order Cyprinodontiformes consisting of three Family (biology), families which are commonly known as killifishes. Families The three families within the suborder Aplocheiloidei are: * Aplochei ...

into a single family Aplocheilidae, with the subfamilies Aplocheilinae, Nothobranchiinae and the Cynolebiinae. However, the 5th edition of ''

Fishes of the World ''Fishes of the World'' is a standard reference for the systematics of fishes. It was first written in 1976 by the American ichthyologist Joseph S. Nelson (1937–2011). Now in its fifth edition (2016), the work is a comprehensive overview of t ...

'' retains the three families Aplocheilidae,

Nothobranchiidae Nothobranchiidae are a Family (biology), family of Osteichthyes, bony fishes containing roughly 300 species, also known as African rivulines. They are small killifish, usually measuring about . They are limited to Africa, living in fresh water bu ...

and Rivulidae.

Genera

The following genera are classified in the family Rivulidae: The taxonomy of this family is subject to some discussion among workers and some of the listed genera are considered to be

paraphyletic Paraphyly is a taxonomic term describing a grouping that consists of the grouping's last common ancestor and some but not all of its descendant lineages. The grouping is said to be paraphyletic ''with respect to'' the excluded subgroups. In co ...

, for example it has been posited that ''

Leptolebias ''Leptolebias'' is a ray-finned fish genus of the killifish family Rivulidae. Like many of their relatives, they are rather ambiguously known as "pearlfish". They are endemic to the coastal areas of Brazil, where they inhabit ephemeral pools in ...

'' is paraphyletic if the species placed in ''

Leptopanchax ''Leptopanchax'' is a genus of small fish, up to long, in the family Rivulidae. They are found in southeastern Brazil from Paraná to Rio de Janeiro. Depending on the exact species, they inhabit small seasonal channels in the Atlantic rainfore ...

'' are retained within it, as per

Fishbase FishBase is a global species database of fish species (specifically finfish). It is the largest and most extensively accessed online database on adult finfish on the web.

. * ''

Anablepsoides ''Anablepsoides'' is a genus of killifish in the family (biology), family Rivulidae native to tropical South America and the Lesser Antilles. The majority are from the Amazon basin, Amazon and Orinoco basins, as well as freshwater systems in the ...

Huber Huber is a German-language surname. It derives from the German word meaning hide, a unit of land a farmer might possess, granting them the status of a free tenant. It is in the top ten most common surnames in the German-speaking world, especial ...

, 1992 * ''

Aphyolebias ''Aphyolebias'' is a genus of New World killifish from the family Rivulidae. Although this genus is recognised by Fishbase In 1998, it was suggested that several species from the genus '' Moema'' be moved to the new ''Aphyolebias''. Genetic rese ...

'' Costa, 1998 * ''

Atlantirivulus ''Atlantirivulus'' is a genus of fishes in the family Rivulidae. They are endemic to shallow swamps, creeks, streams and pools in the Atlantic Forest in southeastern Brazil, ranging from Rio de Janeiro to Santa Catarina. Several of the species ...

'' Costa, 2008 * ''

Austrofundulus ''Austrofundulus'' is a genus of killifish in the family Rivulidae native to northern Colombia, northern Venezuela and southwestern Guyana. They are annual killifish where adults generally have a short life in temporary ponds or swamps and the eg ...

Myers Myers as a surname has several possible origins, e.g. Old French ("physician"), Old English ("mayor"), and Old Norse ("marsh"). People * Abram F. Myers (1889–after 1960), chair of the Federal Trade Commission and later general counsel and b ...

, 1932 * ''

Austrolebias ''Austrolebias nigripinnis'', also known as blackfin pearlfish, is an ephemeral killifish in the family Rivulidae. These annual killifish lives in temporary water bodies during the season, thus it undergoes its entire life cycle within the peri ...

'' Costa, 1998 * ''

Campellolebias ''Campellolebias'' is a genus of killifish in the family Rivulidae from southeast Brazil. They are restricted to seasonal blackwater pools in forests in coastal parts of Santa Catarina and São Paulo states. They are small fish, up to in tota ...

'' Vaz-Ferreira & Sierra de Soriano, 1974 * ''

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 C ...

Meek Meekness is an attribute of human nature and behavior that has been defined as an amalgam of righteousness, inner humility, and patience. Meekness has been contrasted with humility alone insomuch as humility simply refers to an attitude towards o ...

, 1904 * ''

Cynolebias ''Cynolebias'' is a genus of freshwater annual killifish in the family Rivulidae. They are endemic to northeastern Brazil, generally in temporary waters such as ponds in the Caatinga and adjacent regions. By far the highest species richness is ...

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 descri ...

, 1876 * '' Cynopoecilus'' Regan, 1912 * '' Gnatholebias'' Costa, 1998 * '' Hypsolebias'' Costa, 2006 * '' Kryptolebias'' Costa, 2004 * ''

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 ...

'' Huber, 1999 * ''

'' Myers, 1952 * '' Llanolebias'' Hrbek & Taphorn, 2008 * '' Maratecoara'' Costa, 1995 * ''

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 ...

'' Costa, 2006 * '' Micromoema'' Costa, 1998 * '' Millerichthys'' Costa, 1995 * '' Moema'' Costa, 1989 * '' Mucurilebias'' Costa, 2014 * '' Nematolebias'' Costa, 1998 * '' Neofundulus'' Myers, 1924 * '' Notholebias'' Costa, 2008 * '' Ophthalmolebias'' Costa, 2006 * '' Papiliolebias'' Costa, 1998 * '' Pituna'' Costa, 1989 * '' Plesiolebias'' Costa, 1989 * '' Prorivulus'' Costa, Lima & Suzart, 2004 * '' Pterolebias'' Garman, 1895 * '' Rachovia'' Myers, 1927 * '' Renova'' Thomerson & Taphorn, 1995 * ''

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 g ...

'' Poey, 1860 * '' Simpsonichthys'' Carvalho, 1959 * '' Spectrolebias'' Costa & Nielsen, 1997 * '' Stenolebias'' Costa, 1995 * '' Terranatos'' Taphorn & Thomerson, 1978 * '' Trigonectes'' Myers, 1925 * '' Xenurolebias'' Costa, 2006

References

{{Taxonbar, from=Q132133 * Percomorpha families Taxa named by George S. Myers