Foraging behavior of pollinators
At our study site,H. mutabilis was visited by five insect species (Fig. 4), including four bee species (Xylocopa appendiculata , Xylocopa dissimilis ,Bombus breviceps , and Apis mellifera ) (Fig. 4A~F) and one moth species (Macroglossum pyrrhosticta ) (Fig. 4G and H). The body length (12.58 ± 0.18 mm, N = 10) and intertegular distance (3.29 ± 0.07 mm, N = 10) of A. mellifera were the smallest among five visitor species (Wald χ2 = 4738.98, df = 4, P< 0.001, and Wald χ2 = 1877.37, df = 4,P < 0.001) (Fig. 5B and C), but the visitation rate (0.92 ± 0.08 visits per flower per 30 min, N = 128) ofA.mellifera was the highest among five visitor species (Wald χ2 = 253.16, df = 4, P < 0.001) (Fig. 5D). The body length (31.72 ± 0.18 mm, N = 10) and intertegular distance (6.52 ± 0.08 mm, N = 10) of M. pyrrhosticta were relatively larger than that of X. dissimilis (21.37 ± 0.22 mm and 5.59 ± 0.09 mm, N = 10, P < 0.001) (Fig. 5A and B), B. breviceps (17.96 ± 0.22 mm and 5.52 ± 0.03 mm, N = 10, P< 0.001) (Fig. 5B and C), and A. mellifera (P< 0.001) (Fig. 5B and C), but the visitation rate (0.12 ± 0.02 visits per flower per 30 min, N = 128) of M. pyrrhosticta was relatively lower than that of B. breviceps (0.38 ± 0.05 visits per flower per 30 min, N = 128, P < 0.001) (Fig. 5D), and A. mellifera (P < 0.001) (Fig. 5D). All visitor species did not actively collect the pollen grains of H. mutabilis . When they entered the corolla of flowers to forage for nectar, they would remove pollen grains from mature anthers and deposit pollen grains on the stigma. Therefore, all visitor species served as effective pollinators of H. mutabilis .