Habitat Response Variability: Modeling Predictions Display the Expansion–Contraction Scenario of Two Chinese Endangered Cheirotonus Beetles Under Climate Change

Predicting the potential adaptation zones of Cheirotonus gestroi Pouillaude and Cheirotonus jansoni Jordan under the influence of climate change is essential for understanding their geographical distribution and informing effective species conservation strategies. Species distribution models (SDMs), particularly the MaxEnt model, enable researchers to estimate habitat suitability based on current and future environmental conditions. In this study, we employed the optimized MaxEnt model in combination with ArcGIS software to predict suitable habitats under both present and future climate scenarios (2050s and 2070s), and to identify key environmental variables influencing their geographical distribution. For C. jansoni, the influential factors were temperature seasonality (bio4; 31.8%), Elevation (Elev; 28.8%), and precipitation of the driest month (bio14; 24.2%). Currently, its suitable habitats are mainly located in the southeastern part of China, including Zhejiang, Fujian, Hunan, Guizhou, Guangdong, Guangxi, Anhui, Hainan, and Taiwan. Habitat suitability for this species is projected to expand under most climate change scenarios. Conversely, the distribution of C. gestroi is primarily shaped by Isothermality (bio3; 68.4%), the Normalized Difference Vegetation Index (NDVI; 19.5%) and Temperature annual range (bio7; 11.7%). This species' suitable habitats are currently concentrated in Yunnan province in southwestern China, with a predicted contraction in habitat range under future climate conditions. The MaxEnt model predictions reveal clear differences in the ecological niches and habitat preferences of these two beetle species, indicating that C. jansoni exhibits greater environmental adaptability compared to C. gestroi. These findings offer valuable insights for developing targeted monitoring and conservation strategies for these endangered beetles in the face of ongoing climate change.