''Parapimelodus'' is a small

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

long-whiskered catfish The Pimelodidae, commonly known as the long-whiskered catfishes, are a family of catfishes (order Siluriformes). Taxonomy The family Pimelodidae has undergone much revision. Currently, it contains about 30 genera and about 90 recognized and know ...

es native 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 ...

Species

There are currently two recognized species in this genus: * '' Parapimelodus nigribarbis'' ( Boulenger, 1889) * '' Parapimelodus valenciennis'' ( Lütken, 1874)

Distribution

The two species of ''Parapimelodus'' are isolated from each other. ''P. valenciennis'' is known from the

Uruguay Uruguay, officially the Oriental Republic of Uruguay, is a country in South America. It shares borders with Argentina to its west and southwest and Brazil to its north and northeast, while bordering the Río de la Plata to the south and the A ...

La Plata La Plata () is the capital city of Buenos Aires province, Argentina. According to the 2022 Argentina census, census, the La Plata Partido, Partido has a population of 772,618 and its metropolitan area, the Greater La Plata, has 938,287 inhabit ...

Paraguay Paraguay, officially the Republic of Paraguay, is a landlocked country in South America. It is bordered by Argentina to the Argentina–Paraguay border, south and southwest, Brazil to the Brazil–Paraguay border, east and northeast, and Boli ...

, and the lower to middle

Paraná River The Paraná River ( ; ; ) is a river in south-central South America, running through Brazil, Paraguay, and Argentina for some ."Parana River". Encyclopædia Britannica. Encyclopædia Britannica Online. Encyclopædia Britannica Inc., 2012. Web. ...

s. ''P. nigribarbis'' is restricted to the

Lagoa dos Patos Lagoa (Portuguese for ''lagoon'') may refer to the following: People * Barbara Lagoa, Cuban-American federal judge Places Brazil * Campina da Lagoa, Paraná * Lagoa, Paraíba, Paraíba * Lagoa, Rio de Janeiro, a quarter of Rio de Janeiro * Lagoa ...

system.

Description

The body is compressed and becomes strongly compressed at the tail. The head is slightly depressed and the mouth is slightly inferior, with the upper jaw longer than the lower jaw. There is one pair of maxillary barbels and two

mental Mental may refer to: * of or relating to the mind Films * ''Mental'' (2012 film), an Australian comedy-drama film starring Toni Collette * ''Mental'' (2016 film), a Bangladeshi romantic-action film starring Shakib Khan * ''Mental'', a 2008 docu ...

. The dorsal and pectoral fin spines are strong and pungent. These fish have a silvery-grey dorsal surface and a whitish or slightly yellowish ventral surface. The barbels are usually dark. Unpaired fins are usually strongly pigmented with

melanophore Chromatophores are cells that produce color, of which many types are pigment-containing cells, or groups of cells, found in a wide range of animals including amphibians, fish, reptiles, crustaceans and cephalopods. Mammals and birds, in contrast ...

s, while paired fins are less strongly pigmented.

Ecology

Species of ''Parapimelodus'' have extremely long

gill raker Gill rakers in fish are bony or cartilaginous processes that project from the branchial arch (gill arch) and are involved with suspension feeding tiny prey. They are not to be confused with the gill filaments that compose the fleshy part of th ...

s and more than 55

s on the first branchial arch, which is related to feeding on

plankton Plankton are the diverse collection of organisms that drift in Hydrosphere, water (or atmosphere, air) but are unable to actively propel themselves against ocean current, currents (or wind). The individual organisms constituting plankton are ca ...

. They also have very large eyes on the sides of the head that can be seen both from above and below, which is related to independence from the bottom in locomotion and feeding; though a common trait in many other catfish, it is rare in Pimelodids. ''P. valenciennis'' has a possible greater abundance in lagoons than other catfish. ''P. nigribarbis'' is the most abundant species in beam trawling at the Saco de Tapes, Lagoa dos Patos.

References

{{Authority control Pimelodidae Fish of South America Catfish genera Freshwater fish genera