Potential role of damselflies in the pollination of Callitriche rimosa Fasset

While most flowering plant species rely on animal pollinators, approximately 10% of angiosperms utilize wind or water for pollination. Moreover, certain species can have mixed pollination system—ambophily—wherein both biotic and abiotic agents contribute to pollen transport. Upon frequent observation of damselflies (Coenagrionidae) perching on Callitriche rimosa Fassetv (Plantaginaceae), an aquatic herb with small flowers protruding above the water's surface, we hypothesized their potential contribution to the pollination of this primarily abiotically pollinated plant. Observations were conducted along the shores of a pond in southern Brazil. Damselflies were seen carrying pollen grains on their legs from C. rimosa leaves, where pollen falls from the anthers and remains exposed. Given damselflies' activity levels during summer, incidental contact with C. rimosa reproductive structures facilitates cross-pollination. This interaction may facilitate both plants and insects, considering damselflies' dependence on freshwater bodies and use of C. rimosa leaves for perching. Accessory pollen presentation on leaves may convert occasional visitors into pollinators, expanding the pollination niche of C. rimosa. Recognizing lesser-known pollinators like damselflies is crucial for understanding plant reproduction in diverse ecosystems.