Abstract: Chroogomphus rutilus is a large edible and medicinal fungus of significant economic value. We utilized the Biomod2 ensemble model to predict the distribution of C. rutilus for the present and future periods (the 2050s and 2070s) under four Shared Socioeconomic Pathway scenarios (SSP126, SSP245, SSP370, and SSP585). Among the ten individual models integrated into the Biomod2 ensemble, the eXtreme Gradient Boosting (XGBOOST) model yielded the highest values for both the receiver operating characteristic (ROC) curve and the true skill statistic (TSS), indicating that it was the optimal model. Conversely, the surface range envelope (SRE) modelhad the lowest scores. The final ensemble model achieved an ROC value of 0.993 and a TSS value of 0.972, demonstrating high predictive accuracy and reliable simulation outcomes. Precipitation of the wettest quarter was identified as the primary variable influencing the distribution of C. rutilus. The response curves of environmental variables indicated that the species preferred humid and warm growing conditions. Currently, the suitable habitats of C. rutilus are primarily located in Hulunbuir City, Hinggan League, Tongliao City, Chifeng City, and Xilingol League, covering a total area of 40.363×10⁴ km². Under future climate scenarios, its suitable habitat in Hulunbuir City is projected to expand, with a migratory trend towards the southwest, particularly under medium to high emission scenarios (SSP245, SSP370, and SSP585). Furthermore, dynamic niche modeling suggests that as the intensity of greenhouse gas emissions increases, the niche stability of C. rutilus will decrease, potentially leading to significant shifts in its core suitable habitats.

Key words: Chroogomphus rutilus, species distribution model, ensemble approach, suitable habitat, Biomod2, niche