Abstract
Marcomeria viridiflora (Boraginaceae) is pollinated by broad-tailed and rufous hummingbirds in the White Mountains of Arizona. This is the first hummingbird-pollinated member of the family Boraginaceae to be recorded in western North America. It provides one more example of a predominantly beepollinated plant group that has given rise to one or a few exceptional species of hummingbird flowers in western North America.