Unveiling Wasps as Potential Pollinators: Floral Traits and Wasp Sociality Intensify Network Centrality in a Highly Diverse Tropical Ecosystem

Abstract

ABSTRACT Wasps, members of over 90 hymenopteran families, exhibit diverse behaviours, including pollination, predation and parasitism. While wasps are known pollinators in specialised systems, such as the intricate mutualism of fig trees and the deceptive pollination of certain orchids, they have historically been considered ineffective pollinators, with their role often overlooked. Despite frequent visits to flowers, especially in neotropical savannas like the Cerrado, the wasp and floral traits associated with wasp visitation and their influence on plant–pollinator networks are still poorly understood. This study consolidates data on flower–wasp interactions in the Cerrado, Brazilian biodiversity hotspot to explore how floral and wasp traits shape interaction networks. We constructed a mutualistic interaction network comprising 185 wasp species and 144 plant species, performing 728 interactions, and calculated centrality indices. We assessed whether wasp traits (e.g., sociality, life form) and floral traits (e.g., symmetry, anthesis time, inflorescence type) predict network centrality. Social Vespidae wasps, particularly Brachygastra and Polybia species, were frequent floral visitors. Most plants had small, actinomorphic, nectar‐rewarding flowers, with crepuscular anthesis and inflorescence architecture increasing plant centrality. Sociality increased wasp centrality, indicating that behavioural traits enhance their role in network cohesion. This study underscores that wasps may play a significant yet underappreciated role in pollination, particularly in generalist flowers. By identifying the floral traits most associated with wasp visitation, this study advances our understanding of wasps as potential pollinators in diverse plant communities. These findings suggest the need for further research on wasp pollination behaviour, especially to evaluate their effectiveness as pollinators. Understanding the contributions of wasps could provide critical insights for the pollination of endemic and endangered species, supporting conservation efforts in the Cerrado's biodiverse and threatened ecosystems.