Proboscis Extension Reflex in Apis florea (Hymenoptera: Apidae) in Response to Temperature

Abstract

Abstract Increased atmospheric temperatures may negatively affect the ecology, biology, and physiology of insect pollinators by increasing asynchrony between pollinator foraging and flowering of angiosperms. Apis florea F. (Hymentoptera: Apidae) is an important pollinator of vegetables and spice plants in India and, compared to other honeybee species native to Asia, tolerates higher temperatures. We tested the effects of three temperatures (25°C ± 0.5°C, 35°C ± 0.5°C, and 42°C ± 0.5°C) on changes in proboscis extension reflex (PER) in A. florea in response to increasing sucrose concentrations (3%, 10%, 30%, 40%, 50%, and 70% w/v). Across the six sucrose concentrations, the mean %PER scores of A. florea exposed to 25°C ± 0.5°C were significantly higher than those at 35°C ± 0.5°C and 42°C ± 0.5°C, although the mean %PER scores at 35°C ± 0.5°C and 42°C ± 0.5°C did not vary significantly. This result suggests a possible reduction in A. florea feeding motivation at temperatures above 25°C, which may negatively affect their winter foraging patterns. This could be especially problematic with rising minimum air temperatures in the semiarid lateritic belts of West Bengal, India.