Flower visitation by hoverflies (Diptera: Syrphidae) in a temperate plant-pollinator network
- Published
- Accepted
- Subject Areas
- Biodiversity, Ecology, Entomology
- Keywords
- pollination, plant-pollinator interactions, foraging, hoverflies, species traits
- Copyright
- © 2018 Klecka et al.
- Licence
- This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ Preprints) and either DOI or URL of the article must be cited.
- Cite this article
- 2018. Flower visitation by hoverflies (Diptera: Syrphidae) in a temperate plant-pollinator network. PeerJ Preprints 6:e26516v2 https://doi.org/10.7287/peerj.preprints.26516v2
Abstract
Hoverflies (Diptera: Syrphidae) are among the most important pollinators, although they attract less attention than bees. They are usually thought to be rather opportunistic flower visitors, although previous studied demonstrated that they show colour preferences and their nectar feeding is affected by morphological constraints related to flower morphology. Despite the growing appreciation of hoverflies and other non-bee insects as pollinators, there is a lack of community-wide studies of flower visitation by syrphids. The aim of this paper is to provide a detailed analysis of flower visitation patterns in a species rich community of syrphids in a Central European grassland and to evaluate how species traits shape the structure of the plant-hoverfly flower visitation network. We found that different species varied in the level of specialisation, and while some species visited a similar spectre of flowers, others partitioned resources more strongly. There was a consistent difference in both specialisation and flower preferences between three syrphid subfamilies. Eristalinae and Pipizinae were more specialised than Syrphinae. Trait-based analyses showed that relative flower visitation i) increased with plant height, but most strongly in Eristalinae; ii) increased with inflorescence size in small species from all three subfamilies, but was independent of inflorescence size in large species of Eristalinae and Syrphinae; and iii) depended on flower colour, but in a subfamily-specific way. Eristalinae showed the strongest flower colour preferences for white flowers, Pipizinae visited mostly white and yellow flowers, while Syrphinae were less affected by flower colour. Exploration of the structure of the plant-hoverfly flower visitation network showed that the network was both modular and nested. We also found that there were almost no differences in specialisation and relative visitation frequency between males and females. Overall, we showed that flower visitation in syrphids was affected by phylogenetic relatedness, body size of syrphids and several plant traits.
Author Comment
This version includes changes in response to comments by three reviewers and numerous minor improvements and corrections. Specifically, we included a map of the study site's location as new Fig. 1, corrected several errors in terminology and species identification, which had no effect on the interpretation of the results, revised the entire text for clarity and expanded the description of methods and the discussion.
Supplemental Information
Visitation of flowers of individual plant species by selected species of hoverflies, separately by males and females
Raw data on flower visitation by hoverflies
The dataset contains all observations of flower visits. Each hoverfly individual is recorded in a separate row and information about its identity, sex, sampling location, and plant species on whose flower it was collected is provided.
The complete plant-hoverfly flower visitation network
The network is shown as a matrix with hoverflies in rows and plants in columns. Number of flower visits recorded is provided for each plant-hoverfly species combination. The first column provides hoverfly species ID number and the first raw provides plant species ID number used in Fig. 1 in the main text.
Values of diet overlap for all pairs of hoverfly species
We show values of the Pianka's niche overlap index calculated from flower visitation data. Species of hoverflies with <5 records were excluded from the calculations.
A summary of plant species trait measurements
Mean value of plant height and inflorescence size, and flower colour is provided for all plant species visited by hoverflies during our study.