Key to the species of Brycon occurring in Espírito Santo State (adapted from Lima (2017)):

1. Fifth infraorbital bone wider than high; head profile distinctly pointed........................................... 2

- Fifth infraorbital bone about as wide as high; head profile either obtuse or pointed................................. 3

2. Caudal, dorsal, and anal fins carmine-red in life, light-colored in preserved specimens................. Brycon vermelha

- Caudal, dorsal, and anal fins darkened in both living and preserved specimens......................... Brycon insignis

3. Head profile distinctly pointed, including snout............................................................. 4

- Head profile approximately obtuse, including snout............................................. Brycon opalinus

4. Mouth distinctly anisognathous, premaxillary pointed, extending beyond dentary, leaving outer, and often second, premaxillary tooth row exposed in ventral view............................................................... Brycon ferox

- Mouth approximately isognathous, premaxillary and dentary mostly overlapping, leaving only part of outer premaxillary series exposed in ventral view in some specimens...................................................... Brycon dulcis