Geographic variations of floral traits and pollinator guilds in a specialized pollination mutualism, Kadsura longipedunculata and gall midges
image: The male flowers of Kadsura longipedunculata exhibit variations in flower morphology, color, and scent among different populations. However, the obligate midge pollinators show consistent pollinating behaviors and shared midge species across different color morphs and populations.
Credit: Kai Hao, You-Heng Wu, Qi-Lin Sun, Wen-Cai Dong, and Shi-Xiao Luo.
Date: April 26, 2026
Guangzhou, China: A research team led by Prof. Shi-Xiao Luo from the South China Botanical Garden, Chinese Academy of Sciences, has published new findings on geographic variations in floral traits and pollinator guilds in a specialized brood pollination system, offering fresh empirical evidence for coevolutionary dynamics across populations.
Published in Biological Diversity, the study focused on Kadsura longipedunculata (Schisandraceae), a widespread basal angiosperm pollinated by ovipositing gall midges. The team investigated floral morphology, color dimorphism, and scent chemistry across three key populations in southern China, combining field surveys, herbarium records, GC–MS scent analysis, and DNA barcoding of pollinators.
Key results show striking geographic patterns:
- Male flowers display androecium color dimorphism (red/yellow), mostly monomorphic across sites but polymorphic in a few locations.
- Floral morphology differs significantly among populations, with notably larger stamen chambers in the Xinning population than in Hengshan, potentially linked to midge oviposition traits.
- Floral scents are dominated by terpenes; while compound composition is consistent, relative abundances differ geographically and between color morphs, creating distinct odor profiles.
- Four pollinating Resseliella gall midge species were identified. Partial pollinator sharing occurs across sites: R. kadsurae is shared between Xinning and Hengshan, and another Resseliella sp. between Xinning and Lushan.
Notably, color morphs within the same population share the same primary pollinator, indicating floral trait variation does not trigger pollinator shifts. These patterns align with the geographic mosaic theory, where local adaptation and trait–pollinator matching shape dynamic interactions across ranges.
This work improves understanding of trait evolution and pollinator stability in specialized nursery pollination systems, critical for conserving ancient mutualistic networks in changing environments.
Original Source
Hao, Kai, You-Heng Wu, Qi-Lin Sun, Wen-Cai Dong, and Shi-Xiao Luo. 2024. “Geographic Variations of Floral Traits and Pollinator Guilds in a Specialized Pollination Mutualism, Kadsura longipedunculata and Gall Midges.” Biological Diversity 1(3–4): 110–119.
https://onlinelibrary.wiley.com/doi/10.1002/bod2.12020
Keywords
color dimorphism, geographic trait variations, pollinator sharing, scent differentiation, Schisandraceae, specialized pollination mutualism
About the Author
Kai Hao (First Author), PhD, Assistant Researcher at the South China Botanical Garden, Chinese Academy of Sciences. His research focuses on plant reproductive ecology and evolutionary ecology, particularly the evolution of pollen traits and ecological adaptation strategies in obligate pollination mutualisms.
Shi-Xiao Luo (Corresponding Author), PhD, Herbarium Curator of the South China Botanical Garden, Chinese Academy of Sciences and Director of the South China Plant Identification Center. He specializes in plant–pollinator coevolution and pollinator diversity, and has discovered two novel plant–pollinator symbiotic systems involving Schisandraceae–resin midges and Phyllanthaceae–leafflower moths.
About the Journal
Biological Diversity (ISSN: 2994-4139) is a new open-access, high-impact, English-language journal, devoted to advancing biodiversity conservation, enhancing ecosystem services, and promoting the sustainable use of resources under global change. It features innovative research addressing the global biodiversity crisis.