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 .