Ladybird (Coleoptera: Coccinellidae) Community Dynamics and Climatic Driving Factors in the Taklimakan Desert–Oasis Ecotone

Ladybirds serve as crucial predators in agricultural ecosystems; however, their community dynamics in extremely arid regions are not well understood. We conducted a systematic survey of ladybirds across four habitat types—croplands, orchards, shelterbelts, and weedy margin—at 654 locations in the Taklamakan Desert–oasis ecotone in southern Xinjiang from May to September in 2018, 2019, and 2024. This was done using sweep-netting along with morphological and molecular identification methods. We collected a total of 5414 specimens, representing 23 different species. Hippodamia variegata and Stethorus punctillum were the most prevalent, making up 80.35% of the total individuals. The highest abundance and α-diversity were observed in June, which is significantly earlier than in temperate regions. Climatic factors alone accounted for the largest unique fraction of community variation (14.2%), followed by the shared habitat–month fraction (13.0%), with all predictor sets together explaining 32.5% of the variation. In this extremely arid region, climate accounted for the largest unique fraction among the measured predictor sets, while habitat and month jointly contributed, though 67.5% of community variation remained unexplained. Because climate was strongly confounded with month and geography, this fraction should not be interpreted as evidence of causal dominance. The assembly of ladybird communities was associated with the interaction of climate and habitat, but the relative importance of climate versus habitat requires further experimental validation. These results provide a correlational foundation for understanding ladybird community assembly in oasis agriculture, but further experimental work is needed before they can be translated into specific management actions.