More Than Color: Floral Color Polymorphism Is Associated With Scent Differentiation and Pollination Success in the Deceptive Orchid Anacamptis pyramidalis

ABSTRACT Floral color polymorphism is widespread among flowering plants, yet the mechanisms underlying its maintenance remain poorly understood, particularly in food‐deceptive orchids where pollinator‐mediated selection may differ from that operating in rewarding species. Here, we investigated the relationship among floral color polymorphism, ploidy variation, floral scent composition, and pollination in the Mediterranean deceptive orchid Anacamptis pyramidalis . Cytotypes were determined by flow cytometry, and floral volatile organic compounds (VOCs) were analyzed using gas chromatography–mass spectrometry (GC–MS) in white‐ and pink‐flowered individuals from multiple populations. VOC profiles were compared using multivariate and univariate statistical approaches. Pollination success was assessed in mixed‐color diploid and tetraploid populations by quantifying the number of mature fruits produced per individual. Floral color morph was significantly associated with floral scent composition, accounting for approximately 6.5% of the total multivariate variation. Five VOCs differed significantly in relative abundance after correction for multiple comparisons, whereas total VOC emission did not differ significantly between morphs when cultivated in a common garden. No significant association between VOCs and cytotype was detected. White morphs consistently showed higher pollination success than pink morphs, producing significantly more fruits. By showing that floral color polymorphism is associated with both scent differentiation and differences in pollination success, our study highlights the importance of considering floral polymorphism as an integrated phenotype rather than a simple variation in flower pigmentation and helps explain its maintenance in the natural populations of this orchid.