Allen's hummingbird (Selasphorus sasin) is a species of hummingbird. It is a small bird, with mature adults reaching only 3 to 3.5 in (76 to 89 mm) in length. The male has a green back and forehead, with rust-colored rufous flanks, rump, and tail. The male's throat is an iridescent orange-red. The female and immature Allen's hummingbirds are similarly colored, but lack the iridescent throat patch, instead having a series of speckles on their throats. Females are mostly... (Wikipedia)