elachys, Hyphessobrycon Weitzman [M. J.] 1985:800, Figs. 1-5 [Proceedings of the Biological Society of Washington v. 98 (no. 4); ref. 8125] Río Aguaray-guazu system, 3 kilometers northeast of Lima, San Pedro Dept., Paraguay, 23°55'S, 56°29'W. Holotype: USNM 232393. Paratypes: ANSP 153539 (2); BMNH 1984.12.21.2-3 (2); CAS 56018 (2); MNHNP (2); MZUSP 28655 (4); UMMZ 206595 (26 or 32), 212725 (16); USNM 232381 (1), 268474 (79). Type catalog: Vari & Howe 1991:26 [ref. 19022] but they did not list USNM 232381, Oyakawa 1996:468 [ref. 23140]. •Valid as Hyphessobrycon elachys Weitzman 1985 -- (Weitzman et al. 1986:342 [ref. 5984], Géry & Römer 1997:70 [ref. 23712], Gómez & Chebez 1996:50 [ref. 23791], Britski et al. 1999:41 [ref. 24147], Lima & Malabarba in Reis et al. 2003:136 [ref. 27061], López et al. 2003:27 [ref. 27366], Lucena 2003:95 [ref. 27437], Casciotta et al. 2003:101 [ref. 28130], Menni 2004:77 [ref. 28131], Almirón et al. 2004:674 [ref. 27987], Almirón et al. 2006:895 [ref. 29163], Mirande 2010:511 [ref. 31006], Ingenito et al. 2013:38 [ref. 32568], Carvalho & Langeani 2013:526 [ref. 32913], Sarmiento et al. 2014:184 [ref. 35004], Mirande & Koerber 2015:26 [ref. 35117], Teixeira et al. 2016:474 [ref. 34088], Pastana & Ohara 2016:396 [ref. 34716], Ohara et al. 2017:11 [ref. 35144], Koerber et al. 2017:40 [ref. 35267], Dickens 2019:163 [ref. 37135]). Current status: Valid as Hyphessobrycon elachys Weitzman 1985. Acestrorhamphidae: Hyphessobryconinae. Distribution: South America: Paraguay River basin (Argentina, Brazil, Bolivia and Paraguay). Habitat: freshwater.