This species is distinguished from all its congeners, except Moenkhausia moisae by having more scales in lateral series 43-47 (vs. 23-41); it differs from M. moisae mainly by its colour pattern, which consists of one humeral blotch (vs. two), a moderately sized dark midlateral stripe (vs. narrow dark midlateral line), asymmetrical caudal blotch, continuous anteriorly with midlateral stripe and extending posteriorly to margins of four or five middle caudal-fin rays, although less pigmented on this posterior portion (vs. conspicuous, regularly rounded and symmetrical dark blotch, restricted to end of caudal peduncle and base of caudal fin, not continuous with a midlateral line and not extending to the entire length of median caudal-fin rays); scales along mid-dorsal line between tip of supraoccipital process and origin of dorsal fin forming a regular series (vs. predorsal line of scales irregular, not forming a median series) (Ref. 83482).