Costa's hummingbird (Calypte costae) is named after the French nobleman Louis Marie Pantaleon Costa, Marquis de Beauregard (1806–1864). French ornithologist Jules Bourcier first noted it in 1839, and chose the name. Costa's hummingbird has a vibrant purple cap and throat with the throat feathers flaring out and back behind its head. the female is greyish-green above with a white underbelly. Found in hot, dry habitats like the Sonoran and Mojave deserts, the species is an important pollinator of desert plants and cacti in the Southwestern United States and the Baja California Peninsula of Mexico.