Scientists have described a new species of tetra from the Parana basin in southeastern Brazil.
The new species, which has been named Astyanax totae, was described by Carolina Ferreira Haluch and Vinicius Abilhoa in a paper in the journal Neotropical Ichthyology.
Astyanax totae was found in the Rio Iguacu in the Parana basin during a field expedition and closely resembles a member of the Astyanax scabripinnis species complex of Moreira-Filho and Bertollo, based on its morphological features.
Interestingly, these characid tetras are unusual among the region\'s characiform fishes in that they tend to occur in fast-flowing streams, rather than still or slow moving waters like most other tetras.
Moelcular studies have suggested that A. scabripinnis is, in fact, made up of several species of fish.
This new representative has a distinctive elongated humeral spot (a dark marking behind the opercula) and a dark midlateral stripe running from the blotch to the end of the caudal fin rays.
For more details on identifying the new species see the paper: Carolina Ferreira Haluch and Vinicius Abilhoa (2005) - Astyanax totae, a new characid species (Teleostei: Characidae) from the upper rio Iguacu basin, southeastern Brazil. Neotropical Ichthyology, 3(3):383-388, 2005.