Projected Northward Expansion and Southern Core-Habitat Contraction of Zeugodacus tau in China Under Climate Change: An Optimized MaxEnt Analysis

Global warming is reshaping the climatic suitability of invasive ectotherms. In this study, we used an optimized Maximum Entropy (MaxEnt) model combined with GIS-based centroid tracking to quantify the spatiotemporal changes in the potential climatic suitability of Zeugodacus tau, a major polyphagous quarantine pest, in China. Projections were conducted under the historical baseline climate (1970–2000) and future climate scenarios, including SSP1–2.6, SSP2–4.5, and SSP5–8.5 for the 2050s and 2070s. Here, we projected potential climatic suitability rather than future occurrence or abundance. The model showed high predictive performance (AUC = 0.921). Annual mean temperature (Bio1) and mean diurnal range (Bio2) were identified as the primary environmental variables shaping the species’ climatic suitability. Future projections suggested contrasting spatial changes in climatic suitability, with expansion mainly in northern marginal regions and contraction of the southern highly suitable core area. As winter temperatures increased, the low- and moderate-suitability areas were projected to expand northward into temperate agricultural regions. However, under the extreme warming scenario (SSP5–8.5), the highly suitable core area in southern China was projected to decline by 31.61%, while the centroid of the highly suitable area shifted inland and northwestward by approximately 168 km toward the Wuling Mountains. These spatial patterns may be associated with increasing summer heat stress in low-altitude southern regions, although this mechanism requires further physiological validation. Overall, these findings provide a scientific basis for risk-oriented early warning, quarantine planning, and region-specific pest management under future climate change.