zygonectes, Rivulus Myers [G. S.] 1927:127 [Annals and Magazine of Natural History (Series 9) v. 19 (no. 109); ref. 3098] Vereda, Extrema into Cannabrava [Cana Braqva], Upper River Tocantins basin, Goiás, Brazil. Lectotype: CAS 76314 [ex IU]. Paralectotypes: CAS 76313 [ex IU] (9), 76512 [ex IU and IU 76314] (5). Lectotype selected by Huber 1992:464 [ref. 20639]. •Valid as Rivulus zygonectes Myers 1927 -- (Costa 1989:524 [ref. 14319], Huber 1992:464 [ref. 20639], Costa 1995:216 [ref. 21883], Lazara 2001:287 [ref. 25711], Costa et al. 2003:144 [ref. 26946], Costa 2003:41 [ref. 26966], Costa in Reis et al. 2003:540 [ref. 27061], Costa 2003:2 [ref. 27635], Costa 2006:162 [ref. 28875] in subgenus Melanorivulus, Costa 2006:55 [ref. 28876], Costa 2008:349 [ref. 29385], Costa 2010:369 [ref. 30690], Costa 2010:193 [ref. 31043]). •Valid as Melanorivulus zygonectes (Myers 1927) -- (Costa 2011:241 [ref. 31655], Costa 2013:280 [ref. 22107], Costa et al. 2014:196 [ref. 33400], Nielsen & Pinto 2015:137 [ref. 33903], Nielsen et al. 2016:87 [ref. 34407], Costa 2016:137 [ref. 34900], Costa et al. 2016:270 [ref. 35405], Nielsen 2017:66 [ref. 35340], Deprá et al. 2017:113 [ref. 35503], Nielsen & Britzke 2019:42 [ref. 36525]). Current status: Valid as Melanorivulus zygonectes (Myers 1927). Rivulidae: Rivulinae. Distribution: Middle Tocantins River drainage, Brazil. Habitat: freshwater.