Its back scales are tan-to-cream, and its belly is silvery; the divide between the two colors is marked by a broad iridescent-silver stripe.

[2] It is deep-chested, with its deepest body section just before the dorsal fin, and it has 8–9 pre-dorsal scales; the latter is a feature it only shares with B. marabaixo and B.

[5] Bryconops rheoruber has a broad, iridescent-silver lateral stripe that turns lead-gray when a deceased specimen is preserved in alcohol.

B. rheoruber has been considered a member of subgenus Bryconops since its description in 2019, based on the fact that its maxillaries lack teeth or have a single conical tooth isolated to either side.

[3] Members of Creatochanes are partially characterized by having one to three teeth on both sides, and also by factors like jaw length and the bones surrounding the eyes.

[3] Its natural habitat classifies it as "rheophilic", a word meaning "living in flowing water or strong current".

[13] The establishment of the Xingu Indigenous Park, created in 1961, has helped to protect the territory not only of various endemic fish species, but also of various cultures and peoples that have lived in the area dating back to the 1200s.

[14] The Nascentes da Serra do Cachimbo Biological Reserve, established in 2005, encompasses a great deal of the Rio Iriri.