Utilization of floral rewards in male of long-horned bee throughout their lives

Male solitary bees visit flowers and forage for floral resources (pollen and/or nectar), similar to females. However, little is known about the use of floral resources during this activity. In the present study, we focused on the solitary bee species Eucera spurcatipes Pérez, 1905 (Hymenoptera: Apidae), and investigated whether male individuals of any age continuously feed on floral resources throughout their lives. We collected males visiting red clover flowers from April to May. Wing-wear was used as an indicator of age, and the collected specimens were dissected to differentiate between feeding conditions. Wing-wear stages were positively related to the sampling period. Most individuals fed on nectar, and more than half fed on pollen. The proportion of pollen feeders was not related to age, whereas that of nectar feeders was significantly related to age. Our results suggest that males use pollen and nectar throughout most of their lifetimes.