Data from: The gut microbiota of the pine weevil is similar across Europe and resembles that of other conifer-feeding beetles

The pine weevil (Hylobius abietis, Coleoptera: Curculionidae) is an important pest of conifer seedlings in Europe. Despite its economic importance, little is known about the composition of its gut microbial community and the role it plays in mediating the weevil's ability to utilize conifers as a food source. Here, we characterized the gut bacterial communities of different populations of H. abietis across Europe and compared them to those of other beetles that occupy similar ecological niches. We demonstrate that the microbial community of H. abietis is similar at higher taxonomic levels (family and genus) across locations in Europe, with Wolbachia as the dominant microbe, followed by Enterobacteria and Firmicutes. Despite this similarity, we observed consistent differences between countries and locations, but not sexes. Our meta-analysis demonstrates that the gut bacterial community of the pine weevil is very similar to that of bark beetles that also exploit conifers as a food source. The Enterobacteriaceae symbionts of both host taxa are especially closely related phylogenetically. Conversely, the microbiota of H. abietis is distinct from that of closely related weevils feeding on non-conifer food sources, suggesting that the microbial community of the pine weevil is determined by the environment and may be relevant to host ecology. Furthermore, several H. abietis-associated members of the Enterobacteriaceae family are known to contain genes involved in terpenoid degradation. As such, we hypothesize that the gut microbial community is important for the utilization of conifer seedlings as a food source, either through the detoxification of plant secondary metabolites or supplementation of essential nutrients.

松象鼻虫（Hylobius abietis，鞘翅目：象甲科）是欧洲针叶树幼苗的重要害虫。尽管其具有重要的经济价值，但学界对其肠道微生物群落的组成，以及其在介导象鼻虫利用针叶树作为食物来源的能力中所发挥的作用，仍知之甚少。本研究对欧洲不同地理种群的松象鼻虫肠道细菌群落进行了表征，并将其与占据相似生态位的其他甲虫的肠道细菌群落进行了对比。研究表明，欧洲各地松象鼻虫的肠道微生物群落在较高分类学水平（科与属层面）上具有相似性，其中沃尔巴克氏体（Wolbachia）为优势微生物，其次为肠杆菌类（Enterobacteria）与厚壁菌门（Firmicutes）。尽管存在这种整体相似性，但我们仍观察到不同国家与采样地点间存在一致的群落差异，而性别差异则未显现。本研究的荟萃分析结果显示，松象鼻虫的肠道细菌群落与同样以针叶树为食物来源的小蠹虫的肠道细菌群落极为相似，两类宿主的肠杆菌科共生体在系统发育上尤其近缘。与之相反，松象鼻虫的微生物群落与取食非针叶树食物源的近缘象鼻虫的群落存在显著差异，这表明松象鼻虫的肠道微生物群落由环境决定，且可能与宿主生态息息相关。此外，若干与松象鼻虫共生的肠杆菌科成员，已知携带参与萜类物质降解的相关基因。据此，我们提出假说：肠道微生物群落通过对植物次生代谢产物的解毒作用，或是对必需营养物质的补充，在松象鼻虫利用针叶树幼苗作为食物来源的过程中发挥了重要作用。