Aquatic insects serve as an indicator of wetland quality, guiding wetland conservation. Natural wetlands in Suzhou account for 1/3 of the city area, the highest among all Chinese cities, while the biodiversity of aquatic insects remains largely unknown. Here, we collected dragonflies and damselflies, both adults and nymphs for Odonata survey. DNA barcoding(1), allowing non-taxonomist to do species classification efficiently, was applied and identified 14 dragonflies and 14 damselflies. In parallel, gut microbiota was increasingly appreciated for host health and adaptation(2-4), and using metagenome shotgun sequencing, we learned Odonata gut bacteriome predominated by proteobacteria.