Incidence of Wolbachia in aquatic insects.

Eric J Sazama,Jeff S Wesner,Carmelita S Shouldis,Michael J Bosch,Scot P Ouellette

doi:10.1002/ece3.2742

Abstract

Wolbachia is a genus of intracellular bacteria typically found within the reproductive systems of insects that manipulates those systems of their hosts. While current estimates of Wolbachia incidence suggest that it infects approximately half of all arthropod species, these estimates are based almost entirely on terrestrial insects. No systematic survey of Wolbachia in aquatic insects has been performed. To estimate Wolbachia incidence among aquatic insect species, we combined field‐collected samples from the Missouri River (251 samples from 58 species) with a global database from previously published surveys. The final database contained 5,598 samples of 2,687 total species (228 aquatic and 2,459 terrestrial). We estimate that 52% (95% CrIs: 44%–60%) of aquatic insect species carry Wolbachia, compared to 60% (58%–63%) of terrestrial insects. Among aquatic insects, infected orders included Odonata, Coleoptera, Trichoptera, Ephemeroptera, Diptera, Hemiptera, and Plecoptera. Incidence was highest within aquatic Diptera and Hemiptera (69%), Odonata (50%), and Coleoptera (53%), and was lowest within Ephemeroptera (13%). These results indicate that Wolbachia is common among aquatic insects, but incidence varies widely across orders and is especially uncertain in those orders with low sample sizes such as Ephemeroptera, Plecoptera, and Trichoptera.

Highlights

Wolbachia is a genus of bacteria found within the tissues of several groups of arthropods (Pietri, DeBruhl, & Sullivan, 2016; Werren, Baldo, & Clark, 2008)
Despite the high incidence among arthropods in general, little research exists on the incidence of Wolbachia in aquatic insects, defined as insects whose larval stages are in freshwater aquatic environments
We estimate that 52% (CrIs: 44%–60%) of aquatic insect species are infected with Wolbachia versus 60% (58%–63%) of terrestrial insects

Summary

| INTRODUCTION

Wolbachia is a genus of bacteria found within the tissues of several groups of arthropods (Pietri, DeBruhl, & Sullivan, 2016; Werren, Baldo, & Clark, 2008). Using data from a recent global meta-analysis (Hilgenboecker et al, 2008), we estimate that less than 5% of tested insect species have aquatic stages in their life-history Those surveys appear to only include the winged stages of some aquatic insects found in terrestrial areas, sampled haphazardly as part of broader. Other studies have tested members of the order Odonata and aquatic Coleoptera (Sontowski, Bernhard, Bleidorn, Schlegel, & Gerth, 2015; Thipaksorn, Jamnongluk, & Kittayapong, 2003), but very few studies have investigated other major aquatic taxa such as Ephemeroptera, Trichoptera, and Plecoptera (but see Werren & Windsor, 2000; Prakash & Puttaraju, 2007; Yun et al, 2014) These types of surveys are important to understand the global infection frequency of Wolbachia so that future research on the potential impact of these bacteria on arthropod populations can be assessed. We suggest that the incidence of Wolbachia in aquatic insects is comparable to that in terrestrial species

| MATERIALS AND METHODS

| DISCUSSION

Findings

DATA ACCESSIBILITY