Interaction with refuse piles is associated with co-occurrence of core gut microbiota in workers of the ant Aphaenogaster picea

Comparing the diversity of gut microbiota between and within social insect colonies can illustrate interactions between bacterial community composition and host behaviour. In many eusocial insect species, different workers exhibit different task behaviours. Evidence of compositional differences between core microbiota in different worker types could suggest a microbial association with the division of labour among workers. Here, we present the core microbiota of <i>Aphaenogaster picea</i> ant workers with different task behaviours. The genus <i>Aphaenogaster</i> is abundant worldwide, yet the associated microbiota of this group is unstudied. Bacterial communities from <i>Aphaenogaster picea</i> gut samples in this study consist of 19 phyla, dominated by Proteobacteria, Cyanobacteria and Firmicutes. Analysis of 16S rRNA gene sequences reveals distinct similarity clustering of <i>Aphaenogaster picea</i> gut bacterial communities in workers that have more interactions with the refuse piles. Though gut bacterial communities of nurse and foraging ants are similar in overall composition and structure, the worker groups differ in relative abundances of dominant taxa. Gut bacterial communities from ants that have more interactions with refuse piles are dominated by amplicon sequence variants associated with Entomoplasmataceae. Interaction with faecal matter via refuse piles seems to have the greatest impact on microbial taxa distribution, and this effect appears to be independent of worker type. This is the first report surveying the gut microbiome community composition of <i>Aphaenogaster</i> ants.