The RIVOLI is one of the staid and deliberate members of the family. In flight, the outline of its wings is quite perceptible and it is less interested in flowers as a food receptacle. When pursuing an insect in midair the wing "buzz" is heard but in a much lower key than in other Hummers. It watches for prey from a vantage point and darts after victims in regulation Flycatcher fashion.
Mountains of southern Arizona, southwestern New Mexico and extreme western Texas.