Microbial composition of spiny ants (Hymenoptera: Formicidae: Polyrhachis) across their geographic range

Abstract

BackgroundSymbiotic relationships between insects and bacteria are found across almost all insect orders, including Hymenoptera. However there are still many remaining questions about these associations including what factors drive host-associated bacterial composition. To better understand the evolutionary significance of this association in nature, further studies addressing a diversity of hosts across locations and evolutionary history are necessary. Ants of the genus Polyrhachis (spiny ants) are distributed across the Old World and exhibit generalist diets and habits. Using Next Generation Sequencing (NGS) and bioinformatics tools, this study explores the microbial community of >80 species of Polyrhachis distributed across the Old World and compares the microbiota of samples and related hosts across different biogeographic locations and in the context of their phylogenetic history.ResultsThe predominant bacteria across samples were Enterobacteriaceae (Blochmannia - with likely many new strains), followed by Wolbachia (with multiple strains), Lactobacillus, Thiotrichaceae, Acinetobacter, Nocardia, Sodalis, and others. We recovered some exclusive strains of Enterobacteriaceae as specific to some subgenera of Polyrhachis, corroborating the idea of coevolution between host and bacteria for this bacterial group. Our correlation results (partial mantel and mantel tests) found that host phylogeny can influence the overall bacterial community, but that geographic location had no effect.ConclusionsOur work is revealing important aspects of the biology of hosts in structuring the diversity and abundance of these host-associated bacterial communities including the role of host phylogeny and shared evolutionary history.Electronic supplementary materialThe online version of this article (doi:10.1186/s12862-017-0945-8) contains supplementary material, which is available to authorized users.

Can social partnerships influence the microbiome? Insights from ant farmers and their trophobiont mutualists

“…Many of our screened ant workers lacked detectable levels of bacteria, and overall, we only observed seven core OTUs (Figure ). The observed low bacterial density and diversity in Lasius ants were expected given past work on other ant microbiomes, which display similar patterns (Hu et al., ; Moreau & Rubin, ; Ramalho, Bueno, & Moreau, ; Russell et al., , ). While there are exceptions representing a number of highly specialized ant–microbe associations in a handful of specific ant clades (Anderson et al., ; Lukasik et al., ; Russell et al., , ; Sanders et al., ), overall this low density and diversity is in line with previous work (Sanders et al., ).…”

“…In contrast to these highly specific and somewhat diverse microbial associations in the trophobionts, we find little diversity and specificity in the microbiomes of the ant farmers. Instead, the micro- which display similar patterns (Hu et al, 2017;Moreau & Rubin, 2017;Ramalho, Bueno, & Moreau, 2017;Russell et al, 2009Russell et al, , 2017.…”

First Insight into Microbiome Profiles of Myrmecophilous Beetles and Their Host, Red Wood Ant Formica polyctena (Hymenoptera: Formicidae)—A Case Study

“…Nevertheless, those communities may vary from simple to complex and can be influenced by environmental, genetic, and other factors of the host or host's environment (e.g., host diet, phylogeny (coevolution), life stage, host location or pH) [42][43][44][45][46][47]. For many hosts, their phylogeny and diet have a strong effect on associated bacterial communities [48][49][50].…”

Identification and Diversity of Bacterial Communities Associated with the Venom Glands of the Fire Ant, Solenopsis invicta Buren (Hymenoptera: Formicidae)

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