rutilus, Tetragonopterus Jenyns [L.] 1842:125, Pl. 23 (figs. 2, 2a) [The zoology of the voyage of H. M. S. Beagle; ref. 2344] Rio Paraná, South America. Holotype: BMNH 1917.7.14.14. •Treated as a synonym of Astyanax aff. fasciatus (Cuvier 1819) and the same as Astyanax aeneus (Hensel 1870) -- (Malabarba 1989:129 [ref. 14217]). •Synonym of Astyanax fasciatus (Cuvier 1819) -- (Buckup in Reis et al. 2003:109 [ref. 27061]). •Valid as Astyanax rutilus (Jenyns 1842) -- (Protogino et al. 2006:10 [ref. 28780], de Melo & Buckup 2006:46 [ref. 28622], Almirón et al. 2010:67 [ref. 30813], Mirande 2010:516 [ref. 31006] as cf. rutilus, Soneira et al. 2010:785 [ref. 31078], Koerber 2011:3 [ref. 31122], Koerber 2014:5 [ref. 33621], Litz & Koerber 2014:14 [ref. 33622], Mirande & Koerber 2015:24 [ref. 35117], Nión et al. 2016:29 [ref. 35565], Koerber et al. 2017:38 [ref. 35267], Terán et al. 2017:7 [ref. 35358], Dickens 2019:162 [ref. 37135]). •Valid as Psalidodon rutilus (Jenyns 1842) -- (Koerber et al. 2020:4 [ref. 37480], Mirande & Koerber 2020:2 [ref. 37594], Terán et al. 2020:11 [ref. 37440], Koerber et al. 2021:4 [ref. 38894], Koerber et al. 2023:4 [ref. 40355], Loureiro et al. 2023:76 [ref. 40506], Koerber 2024:4 [ref. 41228]). Current status: Valid as Psalidodon rutilus (Jenyns 1842). Acestrorhamphidae: Acestrorhamphinae. Distribution: South America: Río Paraná basin (Argentina, Paraguay and Uruguay). Habitat: freshwater.