Characidium occidentale Buckup & Reis 1997

Dark spots on dorsal fin form a continuous band across rays; anterior portion of anal fin of males with one or two conspicuous dark blotches, followed by smaller spots on the posterior portion. The third or fourth ray of the pelvic fin longest, reaching the area between anal opening and anal fin origin or reaching anal fin origin (Ref. 27672).

Dorsal soft rays (total): 12 - 14; Analsoft rays: 9

Known from the type locality which is a small creek with clear water and slow to moderate current, with loose stones, and in some places, mud on the bottom. Low vegetation are found along stream margins (Ref. 27672).