Small hummingbird with long, curved bill. Male dusky-greenish with contrasting white chest, expansive purple throat, and long forked tail (usually held closed in a point). Female is buffy below with a dusky mask and buffy eyebrow. All ages and sexes are most easily identified by bill shape. Found in deserts; shows a preference for flowering agave plants. Primarily a Mexican species, with very limited range in the U.S. Occurs to just south of Mexico City, where range limit with extremely similar Beautiful Hummingbird is not perfectly known. Male Lucifer has pointed outer tail feathers vs. blunt on Beautiful, but otherwise essentially inseparable.