Mutualistic Pollination Ecology of Swietenia mahagoni (L.) Jacq. and Thrips: A Reproductive Interdependence

Swietenia mahagoni (L.) Jacq., of the family Meliaceae, is economically important for its high-quality timber. S. mahagoni produces very small, pale greenish-yellow, crypto-unisexual flowers arranged in axillary panicles. The male and female flowers are visually identical. The sepals are green, very small, and inconspicuous. The petals are spatulate and pale greenish-yellow in color. The stamens are monadelphous; the flat filaments are laterally fused to form a pitcher-like structure. The female flowers have empty anther lobes, whilst the male blooms carry pollen grains.  The carpels have a stumpy style, a disc-shaped stigma, and are syncarpous. The carpel of the female flower contains functional ovules, whereas ovules, if present, are non-functional in the male flower. A large population of a Thysanopteran insect visits and lays eggs inside the flowers. During oviposition in different flowers, these insects facilitate the transfer of pollen grains from the male to the female flower's stigma. The reproductive ecology and the mutual reproductive dependence between this tree species and the insect have been thoroughly studied in this work.