Astyanax lacustris (Lütken 1875)

Material examined. 1 exemplar; 53.5 mm SL. CI FML 7928, 1 ex, 27°12’ 36.21”S; 65°37’ 22.80”W Pueblo Viejo River.

Identification. Complete lateral line; perforated scales on lateral lines 30–39 (rarely 40 or 41); naked caudal fin; presence of two series of teeth in the premaxilla with 5 teeth in the inner series; maxilla without maxillary teeth; dorsal fin with 9 branched rays; anal fin with 28-30 rays; dark horizontal humeral spot (Lucena and Soares, 2016).