xyrekes, Boulengerella Vari [R. P.] 1995:82, Figs. 46-50 [Smithsonian Contributions to Zoology No. 564; ref. 21840] Cachoeira de Bicho-Açu, about 0°20'S, 65°20'W, Rio Marauiá, Rio Negro basin, Amazonas, Brazil. Holotype: MZUSP 32163. Paratypes: MZUSP 32164 (6), 44743 (2); USNM 324054 (2), 319783 (1, c&s). Plus additional non-type material. Type catalog: Oyakawa 1996:452-453 [ref. 23140]. •Valid as Boulengerella xyrekes Vari 1995 -- (Chang & Ortega 1995:3 [ref. 24302], Vari in Reis et al. 2003:253 [ref. 27061], DoNascimiento et al. 2017:45 [ref. 35633], Meza-Vargas et al. 2021:15 [ref. 39298]). Current status: Valid as Boulengerella xyrekes Vari 1995. Ctenoluciidae. Distribution: South America: Amazon and Orinoco River basins (Brazil, Colombia, Peru and Venezuela). Habitat: freshwater.