Though not well-studied, it has been re-described in recent years in order to differentiate it from Bryconops alburnoides, a congener to which it bears a strong resemblance.

[4] Its body is also on the shallower side when compared to other members of its genus, a feature it shares with B. alburnoides, B. collettei, and B.

This is because they share several morphological traits, such as a yellowish caudal fin, high number of lateral line scales, and overall elongated body shape.

[11] The specific epithet gracilis means "slender" (note the similarity to the word "graceful"), and is in reference to the narrow, elongated body.

[8] Though B. gracilis is currently listed as least concern by the International Union for the Conservation of Nature (IUCN),[1] the Tapajos river is under constant threat of human impact.

[citation needed] Factors like this place B. gracilis, as well as other species endemic to the area, under greater survival pressure.