Astyanax paris: A New Species from the Río Uruguay Basin of Argentina (Characiformes, Characidae)

Abstract

A new species of the characid genus Astyanax is described. The species is currently known only from two localities in headwater streams of arroyo Yabotí-Guazú, a tributary of the upper río Uruguay, in Argentina. Astyanax paris n. sp. can be easily distinguished from all congeneres by the combination of relatively shallow body (34.9–39.4% SL), three or four maxillary teeth, fifth tooth of the inner premaxillary series posterior to main series, first humeral spot followed by a second one vertically elongated, sometimes wider than the first, a caudal spot continued onto the middle caudal fin rays, large dark chromatophores on the cheek, 34–36 perforated scales in the lateral series and, iv–v, 20–22 anal fin rays.