An observation on pollinating insects and their flower-visiting behavior on Fatsia japonica
Fatsia japonica (Thunb.) Dccne. et Planeh is a winter blooming plant. In order to better understand of the pollination ecology of winter blooming plants the insect species visiting F. japonica, their visiting frequency, visiting duration and behavior were observed and recorded. Relatively few insects, mainly wasps and flies, visited F. japonica during winter and the peak of visitation was around midday. The most common visitors were Vespa mandarinia Smith ( Hymenoptera, Vespidae), Scaeva pyrastri ( L. ) ( Diptera, Syrphidae) and Chrysomya ( Compsomyia ) megacephala (Fabricius) (Diptera, Calliphoridae). Visiting frequency differed markedly among these three insects. The peak visiting frequency of Vespa mandarinia and Chrysomya (Compsomyia) megacephala occurred from 10:30 to 14: 30. Scaeva pyrastrifed on the nectar and the pollen of F. japonica and its visiting duration was around 5 to 10 minutes whereas Vespa mandarinia and Chrysomya (Compsomyia) megacephala fed on the nectar and made relatively short visits of 8 to 30 seconds and 3 to 5 seconds, respectively.