Swifts (Apodidae)

Great Dusky Swift (Cypseloides senex) - HBW 5, p. 421

French: Martinet à tête grise German: Rußsegler Spanish: Vencejo Canoso

Taxonomy: Cypselus senex Temminck, 1826, Brazil.
Due to differences in tail and foot structure, species has been placed in genus Aerornis, either alone or with Streptoprocne semicollaris. Monotypic.

Distribution: C & S Brazil, E Paraguay (Oriente) and N Argentina (Misiones); may also breed in Serranía de Huanchaca, NE Bolivia, where recently recorded.