not a species from Argentina:
Pimelodella howesi Fowler, 1940

published in:
Aguilera, G. & M. Azpelicueta (2015):
First record of Pimelodella mucosa Eigenmann & Ward, 1907 (Siluriformes: Heptapteridae) in Formosa, Argentina and comments on the geographical distribution of P. howesi Fowler, 1940.
CheckList 11 (5/1757): 1-3

abstract (from publication):
The examination of the specimens recorded as Pimelodella howesi in Argentina reveals a misidentification that allow us to confirm the presence of Pimelodella mucosa for first time in the country.