Pollination and nesting behaviors of the pollinator (Hymenoptera: Apidae: Anthophora sp.) of a rare legume (Fabaceae: Faboideae: Astragalus phoenix) in Ash Meadows National Wildlife Refuge

Ash Meadows National Wildlife Refuge (AMNWR) is home to many rare, endangered and endemic plants and animals. Among these plants is the Ash Meadows milkvetch, Astragalus phoenix. Astragalus phoenix is a mat growth-form legume common in the alkaline soils of AMNWR; little is known, however, about its insect visitors, their natural history, or the role that insect visitation plays in its reproductive success. We show that the reproductive success of A. phoenix is dependent on pollination services provided by Anthophora sp. We also show that pollination services offered by Anthophora sp. are limited to A. phoenix when its location is coincidental with Anthophora sp. even in the presence of other suitable plants, and we describe the nest architecture and soil preference of Anthophora sp.