The Rivulidae are a

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 ...

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 ...

es in the order

Cyprinodontiformes Cyprinodontiformes is an order of ray-finned fish, comprising mostly small, freshwater fish. Many popular aquarium fish, such as killifish and live-bearers, are included. They are closely related to the Atheriniformes and are occasionally inc ...

. 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 relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southe ...

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

Americas The Americas, which are sometimes collectively called America, are a landmass comprising the totality of North and South America. The Americas make up most of the land in Earth's Western Hemisphere and comprise the New World. Along with th ...

. 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 subfamily botanical names with "-oideae", and zoologi ...

of the

Aplocheilidae Aplocheilidae, the Asian killifishes or Asian rivulines, is a family of fish in the order Cyprinodontiformes found in Asia. Some authorities use this family-group name, which is well-established, for a single lumped aplocheiloid family as it giv ...

. 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. They are considered the most controversial family in the superfamily Noctuoidea because many of the clades are constantly changing, along with the other f ...

s by

Augustus Radcliffe Grote Augustus Radcliffe Grote (February 7, 1841 – September 12, 1903) was a British entomologist who described over 1,000 species of butterflies and moths.Osborn, H. 1937. Fragments of Entomological History. Columbus, OH: Published by the autho ...

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 se ...

, 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 Cyprinodontiformes consisting of three families which are commonly known as killifishes. Families The three families within the suborder Aplocheiloidei are: * Aplocheilidae Bleeker, 1859 * Nothobran ...

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'' by the American ichthyologist Joseph S. Nelson (1937–2011) is a standard reference for fish systematics. Now in its fifth edition (2016), the work is a comprehensive overview of the diversity and classification of the ...

'' retains the three families Aplocheilidae,

Nothobranchiidae Nothobranchiidae are a family of 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 but being also somewhat salt-tol ...

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 In taxonomy (general), taxonomy, a group is paraphyletic if it consists of the group's most recent common ancestor, last common ancestor and most of its descendants, excluding a few Monophyly, monophyletic subgroups. The group is said to be pa ...

, 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.Costa, W.J.E.M. (2016)Comparative morphology and classification of South American cynopoeciline ...

'' 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 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 speci ...

Huber Huber is a German-language surname. It derives from the German word ''Hube'' 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, ...

, 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 res ...

Costa Costa may refer to: Biology * Rib (Latin: ''costa''), in vertebrate anatomy * Costa (botany), the central strand of a plant leaf or thallus * Costa (coral), a stony rib, part of the skeleton of a coral * Costa (entomology), the leading edge of th ...

, 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.Costa, W.J.E.M. (2014)Fo ...

'' 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 ...

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 (born 1889), chair of the Federal Trade Commission and later general counsel and board chai ...

, 1932 * ''

Austrolebias ''Austrolebias'' is a genus of killifish in the family Rivulidae. These annual killifish live in temporary pools, swamps and streams in the Río de la Plata, Patos– Mirim and Mamoré basins in South America. Most species are small, less than ...

'' 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 Co ...

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 i ...

'' Steindachner, 1876 * '' Cynopoecilus''

Regan The family name Regan, along with its cognates O'Regan, O Regan, Reagan, and O'Reagan, is an Anglicized form of the Irish surname Ó Riagáin or Ó Ríogáin, from Ua Riagáin. The meaning is likely to have originated in ancient Gaelic ''ri'' ...

, 1912 * '' Gnatholebias'' Costa, 1998 * ''

Hypsolebias ''Hypsolebias'' is a genus of small fish in the family (biology), family Rivulidae that are endemic the Caatinga, Cerrado and nearby regions in Brazil. The greatest species richness is in the São Francisco River basin, but there are also species ...

'' 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 f ...

'' Costa, 2006 * '' Micromoema'' Costa, 1998 * '' Millerichthys'' Costa, 1995 * '' Moema'' Costa, 1989 * ''

Mucurilebias ''Mucurilebias leitaoi'' is a species of rivulid killifish endemic to Brazil where it occurs, or formerly occurred, in the basin of the Mucuri River. This species can reach a length of TL. This species has not been seen since the original se ...

'' 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 Garman is a surname or first name. Notable people with the name include: Sports * Ann Garman, All-American Girls Professional Baseball League player * Judi Garman (born 1954), American softball coach * Mike Garman (born 1949), American baseball pla ...

, 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 ge ...

'' Poey, 1860 * ''

Simpsonichthys ''Simpsonichthys'' is a genus of killifish from the family Rivulidae the species of which are endemic to temporary freshwater habitats like ponds in the upper Paraná, upper Araguaia, upper Jequitinhonha and São Francisco basins on the centra ...

'' Carvalho, 1959 * '' Spectrolebias'' Costa & Nielsen, 1997 * '' Stenolebias'' Costa, 1995 * ''

Terranatos The saberfin killie (''Terranatos dolichopterus'') is a species of killifish from the family Rivulidae endemic to the Orinoco River basin of Venezuela. This annual killifish grows to in total length. This species is the only known member of it ...

'' Taphorn & Thomerson, 1978 * '' Trigonectes'' Myers, 1925 * '' Xenurolebias'' Costa, 2006

References

* Ray-finned fish families Taxa named by George S. Myers {{Cyprinodontiformes-stub