Hypoptopomatinae is a monophyletic assemblage within the family Loricariidae.[1] It is composed by 17 genera and approximately 80 species.[2] This subfamily represents about one-tenth of all loricariid species.[3]
It is divided into two tribes, Hypoptopomatini and Otothyrini.[1] However, in a 2005 analysis, Otothyrini was found to not be monophyletic, with its representatives comprising a paraphyletic group in relation to the tribe Hypoptopomatini.[4] The most recent hypoptopomatine genus, Gymnotocinclus, was not classified in either of the tribes.[5]
In almost all species of hypoptopomatinae there is a diploid number of 2n = 54; this group is karyotypically very conserved.[6]
Hypoptopomatinae is distributed throughout cis-AndeanSouth America from Venezuela to Northern Argentina.[2] 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.[7]
^ Carvalho, Tiago Pinto; Lehmann A., Pablo; Reis, Roberto E. (2008). "Gymnotocinclus anosteos, a new uniquely-plated genus and species of loricariid catfish (Teleostei: Siluriformes) from the upper rio Tocantins basin, central Brazil". Neotropical Ichthyology6 (3): 329-338.