Disentangling the gut microbiota of the agave weevil, Scyphophorus acupunctatus Gyllenhal, 1838 (Coleoptera: Curculionidae)

The agave weevil, Scyphophorus acupunctatus, is a pest species of agave whose larvae cause damage to agaves by boring holes in the plant. The borer activity requires that the insect consume the constituents of its host plant, which is full of sugar and many recalcitrant polymers. Since many years ago, it has been hypothesized that the gut microbiota of S. acupunctatus larvae plays a role in the metabolization of agave components, but no studies to explore the structure of the gut microbiota of this insect have been performed so far. In this work, we used a 16S rRNA gene-based metabarcoding approach to determine the dynamics of the gut microbiota of field-collected agave weevils from different localities in Mexico. We found that external factors, including host plants, greatly influence the gut bacterial communities of this species. Despite this, we found a discrete core microbiota mainly composed of the genera Prevotella, Pectinatus, Liquorilactobacillus, Secundibacillus, Paucilactobacillus, and Pseudomonas. Our research shows that environmental conditions have a significant effect on the gut microbiota of S. acupunctatus. However, the tight relationship between Prevotella and other genera in the core microbiota could be necessary for the host as metabolic helpers and/or gatekeepers. Additional studies are needed to fully assess the functionality of the gut microbiota in terms of its metabolic contribution, which may help to infer their potential ecological implications, but the information we provided here is the first step to guiding further questions.