Parapimelodus is a small genus of catfishes (order Siluriformes) of the family Pimelodidae. It contains two species, P. nigribarbis and P. valenciennis.
The two species of Parapimelodus
are isolated from each other. P. valenciennis
is known from the Uruguay
, La Plata
, and the lower to middle Paraná Rivers
. P. nigribarbis
is restricted to the Laguna Dos Patos
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
. 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 melanophores, while paired fins are less strongly pigmented.
Species of Parapimelodus
have extremely long gill rakers
and more than 55 gill rakers
on the first branchial arch, which is related to feeding on plankton
. 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, laguna dos Patos.