Assembled contigs for six groups of gut microbiome composition and function of the pygmy grasshopper (Tetrix japonica) across diverse ecosystems in China

The Japanese grasshopper (Tetrix japonica) inhabits various ecosystems across China, providing an ideal model to investigate microbiome-environment interactions. We performed shotgun metagenomic sequencing on gut samples from T. japonica collected across six distinct habitats: coniferous forest (Tja), broadleaf forests in Shandong (Tjb) and Shaanxi (Tjh), grassland (Tjc), shrubland (Tjd), and laboratory-reared populations (Tjg). Field samples were collected from three provinces (Guangxi, Shaanxi, and Shandong) at elevations ranging from 155 to 1,638 meters during June-September of 2023-2024. Each habitat was represented by three pooled replicates (30 females + 30 males per replicate for field samples; 25 females + 25 males for laboratory samples). We identified significant variations in microbial diversity and community structure across habitats. Field populations harbored more diverse microbiomes compared to laboratory-reared insects, with specific bacterial taxa showing strong associations with vegetation types. Core microbiome analysis revealed 23 bacterial genera consistently present across all habitats, suggesting essential symbiotic relationships. Habitat-specific microbial signatures were particularly pronounced between forest and grassland ecosystems, with enrichment of lignocellulose-degrading bacteria in forest habitats. Geographic separation between Shandong and Shaanxi broadleaf forest populations resulted in distinct microbiome profiles despite similar vegetation. Functional analysis revealed habitat-specific metabolic capabilities, including differential abundance of genes involved in plant polymer degradation, nitrogen cycling, and secondary metabolite biosynthesis. Our findings demonstrate that both local environmental conditions and geographic factors significantly influence the gut microbiome assembly of T. japonica. The observed microbiome plasticity likely facilitates host adaptation to diverse dietary resources and environmental conditions. The loss of microbial diversity in laboratory populations highlights the importance of natural habitats in maintaining functional microbiome integrity. These results provide insights into how environmental heterogeneity drives insect-microbe associations and have implications for understanding grasshopper ecology and evolution in changing landscapes.