Abstract
Tetranychus truncatus Ehara, the cotton red spider mite, is an economically significant polyphagous pest that infests economically important crops such as maize, soybean, cotton, and various fruits in China. Its rapid reproduction, broad host range, and increasing insecticide resistance cause significant agricultural and horticultural losses. Although T. truncatus is an ectothermic species highly sensitive to climate variability, how future climate change will affect its geographic range in China remains unclear. Using the optimized maximum entropy (MaxEnt) model, we predicted substantial climate-driven shifts in the distribution of T. truncatus in China, and temperature-related factors were identified as the primary determinants. Under current climatic conditions (1970–2000), approximately 19.32% of China’s territory is suitable for T. truncatus, mainly in eastern and central regions. Projections under three CMIP6 Shared Socioeconomic Pathways (SSP126, SSP245, SSP585) for two future periods (2021–2040 and 2081–2100) suggest substantial northward and coastal expansions across all six future scenarios compared to the current climate conditions, particularly around the Bohai Sea and Yellow Sea. Conversely, habitat suitability in some southern provinces, including Hunan and Guizhou, tended to decline, mainly driven by changes in thermal conditions and secondarily by altered seasonal precipitation conditions. Climate-driven northward expansion and potential increases in voltinism of T. truncatus will intensify agricultural risks, calling for proactive and adaptive pest management strategies. Our findings offer spatially explicit insights for policymakers and agricultural stakeholders, enabling timely implementation of monitoring, prevention, and management measures in newly vulnerable areas.