first record from Argentina:
Hisonotus charrua Almirón, Azpelicueta, Casciotta & Litz, 2006

locality from Argentina:
Entre Rios, Parque Nacional El Palmar, Río Uruguay basin (MACN 7593)

distribution (from publication):
Hisonotus charrua is widely distributed in the middle and lower portions of the rio Uruguai basin from the northern rio Ijuí drainage in the Rio Grande do Sul state, Brazil to the southern Río Negro drainage in the Uruguay. Besides the limits of the rio Uruguai basin, this species is known from the coastal streams of Uruguay, and from a single locality in the headwaters of Sao Goncalo drainage in the Laguna dos Patos system.

published in:
Carvalho, T.P. (2008):
Revisão taxonômica das espécies de Hisonotus Eigenmann & Eigenmann (Siluriformes: Loricariidae) da bacia do rio Uruguai e sistema da laguna dos Patos.
Dissertacao de Mestrado. PUCRS, Porto Allegre, Brazil. 260 pp.