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Bird pollination has evolved in four species of Macaronesian Lotus from a bee-pollinated ancestor. The transition is associated with the modification of several floral traits, including flower color and size, relative size and orientation of the petals, and nectar composition and quantity. Here, we examine petal surface micromorphology in relation to pollination type, using SEM and LM. In the bee-pollinated Lotus (the majority of the genus), papillose conical cells (PCS) are the most abundant epidermal type on dorsal and lateral petals. However, bird-pollinated species completely lack PCS on their dorsal petals and have only a small patch of PCS in a highly localized region of the lateral petal. In the bee-pollinated species (including those most closely related to the bird-pollinated species), PCS develop early in floral development. In contrast, the small amount of residual PCS in bird-pollinated species forms later in …