Females of three of the genera (Ancylandrena, Andrena, and Megandrena) have broad, velvety depressions called "facial foveae" on the face between the eyes and the antennae; in all other members of the family, the foveae are much smaller, typically reduced to grooves or pits at the upper margin of the eyes. Ancylandrena and Megandrena occur only in the desert regions of southwestern North America (Nevada, California, Arizona, Sonora, and Baja California), while Andrena is nearly worldwide. Euherbstia and Orphana are rare bees restricted to desert regions of Chile.
