Delturus
Delturus is a genus of freshwater ray-finned fishes belonging to the family Loricariidae, the suckermouth armored catfishes. It is the type genus of the subfamily Delturinae, the catfishes in this subfamily are known as primitive suckermouth catfishes. These catfishes are endemic to Brazil.
Taxonomy
Delturus was first proposed as a genus in 1889 by the American ichthyologists Carl H. Eigenmann and Rosa Smith Eigenmann with two species, D. angulicauda and D. parahybae, contained within it and with D. parahybae being designated as the type species. In 2006 Roberto Esser [dos Reis], E. H. L. Pereira & Jonathan W. Armbruster proposed the new subfamily Delturinae for ths genus and the related genus, Hemipsilichthys. The subfamily is the sister group to all the other taxa within the Loricariidae, except for the genus Lithogenes. The Loricariidae is classifed within the suborder Loricarioidei of the catfish order Siluriformes.
Etymology
Delturus is a combination of the Greek delta, being the fourth letter in the Greek alphabet, and oura, which means "tail". This is a reference to the triagular cross section of the caudal fin.
Species
Delturus contains the following valid species:
Characteristics
Delturus is distinguished from Hemipsilichthys by their larger size, most species reaching standard lengths up to, more robust bodies, large eyes and the membrane of the dorsal fin extends rearwards and touches the first plat in front of the adipose fin.
Distribution
Delturus catfishes, and the subfamily Delturinae, are endemic to Brazil where they are restricted to the southeastern part of the Brazilian Shield with each species occurring in a different river system. This distribution suggests that southeastern Brazil acts as either a refugium for basal loricariid taxa or the region where the Loricariidae originate.