Astyanax scabripinnis (Jenyns, 1842)

original Tetragonopterus scabripinnis

type locality Rio de Janeiro, Brazil

The subspecies Astyanax scabripinnis paranae was treated as an ‘especie limítrofe’, meaning ‘from neighbouring countries’, by Ringuelet et al. (1967) despite the fact that they cited Pozzi (1945) as the first record from Argentina. López et al. (2003) mention as first record Fernández Santos et al. (1987) who reported Astyanax scabripinnis paranae from the El Palmar National Park in Entre Rios (fig. 1). Additionally they referred to more specimens reported by Miquelarena et al. (1997) from the Urugua-í stream in the Paraná basin of Misiones (fig. 2). Actually in both, the mentioned paper of Miquelarena et al. (1997) and in Miquelarena et al. (2009) these specimens were addressed as the nominal species Astyanax scabripinnis and not as the subspecies A. s. paranae as indicated by López et al. (2003).

Astyanax paranae Eigenmann, 1914 was treated as a valid species by Buckup (2003) and the record by Fernández Santos et al. (1987) would thus be the first one from Argentina for this species. These specimens should be existing yet at the MACN and deserve an examination. Anyhow, if treated as the subspecies as listed by López et al. (2003) and considered currently as a valid species this record cannot refer to Astyanax scabripinnis .

The only remaining record for Astyanax scabripinnis is based on the specimens reported from the Urugua-í subbasin in Misiones. The Urugua-í stream was separated from the Río Paraná by a waterfall until the construction of a hydroelectric dam and has developed its own ichthyofauna, different at least in part from the ones found in the ríos Paraná and Iguazú.

For the specimens from the Urugua-í we consider that these might have been confused with a later described species from the Astyanx scabripinnis complex sensu Ingenito & Duboc (2014). Considering that the arroyo Urugua-í shows an extremely diverse composition of species, possessing species endemic to this subbasin, sharing some with the río Paraná and others with the río Iguazú basin above the falls, the two species which might be candidates for such a confusion are Astyanax leonidas from the Urugua-í itself and A. troya from the río Paraná. Either would more probably be found in the Urugua-í than the real A. scabripinnis or A. paranae . Until an examination of the above mentioned specimens proves us wrong, A. scabripinnis should not be listed in faunal lists for Argentina.