High floral trait diversity of aquatic plants in the Pantanal reveals different pollination strategies

Abstract

This research brings novel information regarding the floral traits and pollinator groups of aquatic macrophytes. Classifying functional traits and pollinator groups contributes to understanding reproductive processes, community structuring, and ecosystem functioning. Based on an extensive survey of information on 524 species of aquatic macrophyte angiosperms from the Pantanal wetland, we classified the floral traits of these species to identify their potential group of pollinators and how these traits are distributed throughout the botanical families of aquatic plants. We classified their life forms, floral traits (flower type, color, and resource), and main pollinator groups. We also investigated trends, plotting the occurrence of species throughout the phylogeny of angiosperm families, and using a network of interactions, we verified how interactions with different groups of pollinators are distributed within species traits. As a result, the species of aquatic macrophytes in the Pantanal are well distributed within the phylogeny, indicating that they may be more related to ecological than phylogenetic factors. We found a high diversity of floral traits and pollinator groups, predominating white flowers, providing nectar as a resource, and bees as their primary pollinators. Although bees were the main group of pollinators, we also found abiotic interactions linked to the species richness in Poaceae and Cyperaceae, with pollination system mainly performed by wind. Our research represents a first step towards identifying key information gaps. Future studies should focus on understanding in loco traits to fill this gap, besides information on ecological interactions with potential pollinators and species phenology.