longum, Characidium Taphorn [D. C.], Montaña [C. G.] & Buckup [P. A.] 2006:3, Fig. 1 [Zootaxa No. 1247; ref. 28733] Rio Capanaparo drainage, Caño La Guardia, 06.84000°N, 67.32500°W, Apure, Venezuela. Holotype: MCNG 53371. Paratypes: Many lots at ANSP, AUM, EBRG, FMNH, MBUCV, MCNG, MHNLS, MNRJ, NRM. Plus non-type material. •Valid as Characidium longum Taphorn, Montaña & Buckup 2006 -- (Peixoto & Wosiacki 2013:56 [ref. 32558], Leitão & Buckup 2014:15 [ref. 33323], DoNascimiento et al. 2017:34 [ref. 35633], Flausino Junior et al. 2020:357 [ref. 37666]). Current status: Valid as Characidium longum Taphorn, Montaña & Buckup 2006. Crenuchidae: Characidiinae. Distribution: Orinoco River and Arapiuns River basins: Brazil, Colombia and Venezuela. Habitat: freshwater.