Abstract:Objective To clarify the diversity characteristics of gut microbiota in the important wild pollinator, Xylocopa appendiculata, and provide theoretical basis for the conservation and utilization of wild pollinator resources.Methods Utilizing employed 16S rRNA gene high-throughput sequencing, we conducted comparative analyses of gut microbiota diversity in adults X. appendiculata from different habitats and sexes. Functional prediction of gut microbial communities was performed using PICRUSt2.Results The gut microbiota in adults X. appendiculata was predominantly composed of Bacillota (relative abundance of 50.17%), Pseudomonadota (relative abundance of 32.04%), Actinomycetota (relative abundance of 12.84%), and Bacteroidota (relative abundance of 3.77%). The genus Lactobacillus was identified as a core microbiota present in all sampled individuals. Significant differences in the relative abundance of gut microbiota were observed across habitats and sexes. The samples from the Sui and Tang Dynasties City Ruins Botanical Garden habitat (HXST) exhibited the highest richness, diversity, and evenness of gut microbiota. In the Sui and Tang Dynasties City Ruins Botanical Garden habitat (ST) and the Caoyao Village habitat (CY), female adults showed higher microbial richness, diversity, and evenness compared to males. In the Shuiquan Village habitat (SQ), male adults showed higher microbial richness, diversity, and evenness compared to females. The genus Gilliamella, as the dominant genus of male samples from Caoyao Village (HXCYM), accounts for a very small proportion in other samples. Functional prediction PICRUSt2 showed that the metabolic gene functions of the gut microbiota of adults X. appendiculata are the most enriched, with an abundance ratio of 74.00%.Conclusion The gut microbiota of adults X. appendiculata exhibits ecological adaptive features with social bees (e.g., Apis mellifera and Bombus spp.), characterized by low diversity, highly conservation, and specialized core microbial community structure. Environmental heterogeneity and host sex were identified as key drivers of gut microbiota divergence. These findings suggest that the gut microbiota of X. appendiculata may play a central role in maintaining host energy homeostasis and population adaptability.