The Oasis Hummingbird is a mid-sized hummingbird that is endemic to South America and restricted to the Pacific coast of Peru and Chile. It is has an olive green back and gray to white breast with a distinctive cinnamon colored rump. It has a long, decurved black bill. Males have brightly iridescent gorget that is blue to red in color and long forked tails. Females have drab whitish below with duskier sides. They have much shorter tail feathers and no iridescent gorget.