melasopterus, Hemigrammus Eigenmann [C. H.] & Kennedy [C. H.] 1903:518 [Proceedings of the Academy of Natural Sciences of Philadelphia v. 55; ref. 1260] Aguada, near Arroyo Trementina, Paraguay. Holotype: CAS 44381 [ex IU 10039]. Paratypes: (6) AMNH 1035 (1), CAS 44382 [ex IU 10040] (1), CAS [ex IU 10041] (orig. 5, not found); FMNH 52668 (2); ZMB 17147 (2). The spelling melasopterus possibly in error for melanopterus. •Synonym of Hyphessobrycon eques (Steindachner 1882) -- (Weitzman & Palmer 1997:224 [ref. 22743], Weitzman & Palmer 1997:148 [ref. 24509], Lima & Malabarba in Reis et al. 2003:136 [ref. 27061], Litz & Koerber 2014:15 [ref. 33622], Mirande & Koerber 2015:26 [ref. 35117], Koerber et al. 2017:41 [ref. 35267]). •Synonym of Megalamphodus eques (Steindachner 1882). Current status: Synonym of Megalamphodus eques (Steindachner 1882). Acestrorhamphidae: Megalamphodinae. Habitat: freshwater.