uruguayensis, Hyphessobrycon melanopleurus Messner [E.] 1962:4 [Boletin de la Asociacion Latino Americana de Ictiologos y Herpetologos v. 2 (no. 1); ref. 23528] Arroyo Tomás Cuadra, tributary of River Negro, Durazno, Uruguay. Syntypes: MHNM 758-759 (1, 1). Type catalog: Olazarri et al. 1970:3 [ref. 23527]; see also Malabarba et al. 2004:101 [ref. 27836], Loureiro et al. 2016:412 [ref. 35150]. •Valid as Cyanocharax uruguayensis (Messner 1962) -- (Malabarba et al. 2004:99 [ref. 27836], Koerber 2011:2 [ref. 31122], Protogino & Miquelarena 2012:581 [ref. 32123], Koerber 2014:4 [ref. 33621], Litz & Koerber 2014:13 [ref. 33622], Mirande & Koerber 2015:22 [ref. 35117], Nión et al. 2016:30 [ref. 35565] with author without parentheses). •Valid as Diapoma uruguayensis (Messner 1962) -- (Thomaz et al. 2015:Add. 5 [ref. 33893], Koerber et al. 2015:2 [ref. 35179], Bertaco et al. 2016:413 [ref. 34561], Koerber & Litz 2016:2 [ref. 35098], Koerber et al. 2017:3 [ref. 35083], Koerber et al. 2019:4 [ref. 36736]). •Valid as Diapoma uruguayense (Messner 1962) -- (Koerber et al. 2017:3 [ref. 35632], Koerber et al. 2020:4 [ref. 37480], Mirande & Koerber 2020:2 [ref. 37594], Koerber et al. 2021:5 [ref. 38894], Ito et al. 2022:19 [ref. 39124], Koerber et al. 2023:5 [ref. 40355], Loureiro et al. 2023:64 [ref. 40506]). Current status: Valid as Diapoma uruguayense (Messner 1962). Stevardiidae: Diapominae. Distribution: South America: Uruguay River basin (Argentina, Brazil and Uruguay). Habitat: freshwater.