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Evidence for pollinator sharing in Mediterranean nectar-mimic orchids: Absence of premating barriers?

The Royal Society
Proceedings of the Royal Society B
Authors:
Salvatore Cozzolino
Salvatore Cozzolino
Salvatore Cozzolino
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Florian P Schiestl at University of Zurich
Florian P Schiestl
Andreas Müller at ETH Zurich
Andreas Müller
Olga De Castro at University of Naples Federico II
Olga De Castro
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Abstract

Pollinator specificity has traditionally been considered the main reproductive isolation mechanism in orchids. Among Mediterranean orchids, however, many species attract and deceive pollinators by mimicking nectar-rewarding plants. To test the extent to which deceptive orchid species share pollinators, we collected and identified hemipollinaria-carrying insects, and used ribosomal sequences to identify the orchid species from which hemipollinaria were removed. We found that social and solitary bees, and also flies, carried hemipollinaria belonging to nine orchid species with different degrees of specialization. In particular, Anacamptis morio, Dactylorhiza romana and Orchis mascula used a large set of pollinator species, whereas others such as Orchis quadripunctata seemed to be pollinated by one pollinator species only. Out of the insects with hemipollinaria, 19% were found to carry hemipollinaria from more than one orchid species, indicating that sympatric food-deceptive orchids can share pollinators. This sharing was apparent even among orchid sister-species, thus revealing an effective overlap in pollinator sets among closely related species. These results suggest varying degrees of pollinator specificity in these orchids, and indicate that pollinator specificity cannot always act as the main isolation mechanism in food-deceptive temperate orchids.
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Article
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  • Jun 2024
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Article
Full-text available
  • Jan 2025
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Preprint
Full-text available
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Chapter
Full-text available
  • Jun 2023
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Chapter
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Preprint
Full-text available
  • Feb 2025
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Article
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  • PLANT BIOLOGY
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Article
Full-text available
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Article
Full-text available
  • Jan 2001
  • ISR J PLANT SCI
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Article
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