The Hypoptopomatinae are 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 ...

catfish Catfish (or catfishes; order Siluriformes or Nematognathi) are a diverse group of ray-finned fish. Named for their prominent barbels, which resemble a cat's whiskers, catfish range in size and behavior from the three largest species alive, ...

es (order Siluriformes) of the family

Loricariidae The Loricariidae is the largest family of catfish (order Siluriformes), with 92 genera and just over 680 species. Loricariids originate from freshwater habitats of Costa Rica, Panama, and tropical and subtropical South America. These fish are not ...

, composed of 17

genera Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nomenclat ...

and approximately 80

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 ...

. This subfamily represents about one-tenth of all loricariid species. It has been divided into two tribes, Hypoptopomatini and Otothyrini. However, in a 2005 analysis, Otothyrini was found to not be monophyletic, with its representatives comprising a

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 ...

group in relation to the tribe Hypoptopomatini. More recent phylogenetic evidence shows that Hypoptopomatini and Otothyrini, while each are monophyletic tribes, do not form a monophyletic subfamily, and therefore should each be recognized as their own individual subfamilies. Problematically, the most recent hypoptopomatine genera, '' Gymnotocinclus'' and ''

Rhinolekos ''Rhinolekos'' is a genus of armored catfishes native to South America. This genus is only known from the Tocantizinho River and Paranaiba River drainage in Goiás, Brazil. Species There are currently 4 recognized species in this genus: * '' ...

'', were not classified in either of the tribes. Almost all species of Hypoptopomatinae have a

diploid number Ploidy () is the number of complete sets of chromosomes in a cell, and hence the number of possible alleles for autosomal and pseudoautosomal genes. Sets of chromosomes refer to the number of maternal and paternal chromosome copies, respective ...

of 2n = 54; this group is karyotypically very conserved. Hypoptopomatinae are distributed east of the

Andes The Andes, Andes Mountains or Andean Mountains (; ) are the longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range is long, wide (widest between 18°S – 20°S ...

in South America from

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 ...

to northern

Argentina Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, th ...

. Most of the hypoptopomatine species are usually found at or near the water surface, typically in close association with riverbank vegetation or some subsurface structure.

References

{{Taxonbar, from=Q136843 Loricariidae Taxa named by Rosa Smith Eigenmann Taxa named by Carl H. Eigenmann Fish subfamilies