Systematics

Among four populations in Costa Rica, Sanchez & Barrantes (unpub. data) found no significant differences for eight body characters. The subspecies bensoni differs from gracilirostris and accentor in the color of the forecrown (blackish brown) and the band across the breast (dark reddish brown) (Wetmore et al. 1984), Furthermore accentor  and bensoni are more reddish brown, with blacker legs and a paler breast-band than nominate gracilirostris.

The systematics of the species has not been resolved. Clement (2003) recognizes two subspecies, nominate gracilirostris and C. g. accentor, but considers these as poorly defined. Collar (2005) recognizes three subspecies: C. g. gracilirostris in Costa Rica, and two from Panama, C. g. accentor from western Chiriquí, and C. g. bensoni from eastern Chiriquí (Wetmore et al. 1984). Further the stated classification do not predict the geographical limits of the subspecies, and are not in accordance to major geographical discontinuities, especially along the almost continuous Talamanca-Chiriqui highlands.