The Swallow-tailed Hummingbird (Eupetomena macroura) is a species in the hummingbird family (Trochilidae), found mainly in east-central South America. Most authorities place it in the monotypic genus Eupetomena, although some place it in Campylopterus based on song and the thick shafts of the males' first primaries. Its common name and specific epithet (which means "large-tailed") both refer to the long, deeply forked, somewhat swallow-like tail.