Redescription of Astyanax stenohalinus Messner, 1962 (Characiformes: Characidae), a poorly known species from Argentina and Uruguay

摘要

Astyanax stenohalinus Messner, 1962 is redescribed based on type material and new specimens collected in many localities of Argentina and Uruguay. This species is distinguished by a combination of the following characters: possession of hooks in all fins of males, teeth not expanded distally, two or three maxillary teeth, 37-39 perforated scales in the lateral series, 25-30 branched anal-fm rays, and anal-fin origin located before a vertical through last dorsal-fin ray insertions.