Persistence of an imperiled specialist bee and its rare host plant in a protected area

The Mojave Desert of the southwestern U.S. is home to two protected species of poppy in the genus Arctomecon Torr. & Frém. (Papaveraceae). A pollinator of these species is the specialist bee Perdita meconis Griswold (Andrenidae) a specialist on poppy pollen. Recently, the easternmost population of P. meconis , which was associated with A. humilis Coville in Utah, has become locally extinct, and other historically associated bee pollinators...