heterodon, Xenurobrycon Weitzman [S. H.] & Fink [S. V.] 1985:88, Figs. 5, 12, 30, 34e, 55, 65 [Smithsonian Contributions to Zoology No. 421; ref. 5203] Río Bobonaza at Sarayacu, Pastaza, 1°16'S, 78°31'W, Ecuador. Holotype: KU 17925. Paratypes: FMNH 87544 (12), 94940 (12); KU 17926 (2); MCZ 54255 (10 or 12); USNM 219389 (2), 219390 (2 c&s), 219391 (12). Type catalog: Vari & Howe 1991:41 [ref. 19022]. •Valid as Xenurobrycon heterodon Weitzman & Fink 1985 -- (Ortega & Vari 1986:10 [ref. 9708], Weitzman 1987:113 [ref. 5982], Malabarba & Weitzman 2000:280 [ref. 24413], Weitzman in Reis et al. 2003:228 [ref. 27061], Moreira 2005:855 [ref. 28474], Barriga Salazar 2014:109 [ref. 35745], Thomaz et al. 2015:Add. 5 [ref. 33893], Mendonça et al. 2016:[7] [ref. 34350], DoNascimiento et al. 2017:54 [ref. 35633], Meza-Vargas et al. 2021:20 [ref. 39298], Menezes & Camelier 2024:285 [ref. 40817]). Current status: Valid as Xenurobrycon heterodon Weitzman & Fink 1985. Characidae: Stevardiinae. Distribution: South America: upper Amazon River basin (Ecuador, Colombia and Peru). Habitat: freshwater.