Contribution of Diurnal and Nocturnal Pollinators to the Reproductive Success of the Orchid species Gymnadenia conopsea.
Meyer, Birgit; Kröger, Jennifer; Steffan-Dewenter, Ingolf
Many orchids depend on animals for pollination and attract pollinators with visual or olfactory cues either during the day, during the night, or both. The relative contribution of nocturnal versus diurnal pollinators to the reproductive success of orchids may differ (Jennersten & Morse 1991). However, pollination by nocturnal insects is poorly investigated in temperate regions. This study compares pollination services of nocturnal and diurnal pollinators to Gymnadenia conopsea. Gymnadenia conopsea (L.) R. Br. (Orchidaceae) is a rare perennial orchid occurring in open grasslands in Europe and Asia, preferably on calcareous soils. The flowers are arranged in a simple spike and vary from violet to pale pink. The orchid is strongly scented, attracting different species of diurnal and nocturnal Lepidopteran pollinators, which are rewarded by a copious amount of nectar from a long, slender spur (Proctor, Yeo & Lack 1996). In 2006, two calcareous grasslands near the city of Göttingen in Southern Lower Saxony, Germany, with large populations of G conopsea were selected for pollination-exclusion-experiments.