crixas, Rivulus Costa [W. J. E. M.] 2007:61, Figs. 6-7 [aqua, International Journal of Ichthyology v. 13 (no. 2); ref. 29394] Stream tributary to Rio Crixás Mirim, ca. 5 kilometers south of Nova Crixás, Rio Crixás Aça drainage, Rio Araguaia basin, at road GO-164 crossing, Goiás State, Brazil, 14°08'11.8"S, 50°21'15.5"W, elevation 284 meters. Holotype: UFRJ 6458. Paratypes: UFRJ 6459 (7), 6460 (5). •Valid as Rivulus crixas Costa 2007 -- (Costa 2010:369 [ref. 30690]). •Valid as Melanorivulus crixas (Costa 2007) -- (Costa 2011:241 [ref. 31655], Costa 2016:144 [ref. 34900], Costa et al. 2016:270 [ref. 35405], Nielsen 2017:67 [ref. 35340], Nielsen & Britzke 2019:42 [ref. 36525]). Current status: Valid as Melanorivulus crixas (Costa 2007). Rivulidae: Rivulinae. Distribution: Middle Araguaia River basin, central Brazil. Habitat: freshwater.