Global climatic co-suitability patterns of the predatory mite Anystis baccarum and green peach aphid Myzus persicae under climate change.

Understanding how climate change alters the geographic correspondence between pests and their natural enemies is important for identifying regions where climatic conditions may support further biological-control assessment. The whirligig mite Anystis baccarum (L.) is a generalist predator known to consume a variety of small arthropod pests, while the green peach aphid Myzus persicae (S.) is a globally invasive pest that damages a wide range of crops. However, the global climatic co-suitability and future geographic correspondence between A. baccarum and M. persicae remain poorly understood. Here, we constructed ensemble species distribution models to predict the climatic suitability and climatically co-suitable areas of both species under current climatic conditions and two climate scenarios for the 2050s, SSP1-2.6 and SSP5-8.5. The ensemble models showed high discrimination under repeated random validation, with AUC values of 0.984 and 0.980 and TSS values of 0.856 and 0.831 for A. baccarum and M. persicae, respectively. The minimum temperature of the coldest month (bio_6) was the most influential climatic predictor associated with the suitability of both species. Under current climatic conditions, predicted suitable areas for both species were concentrated mainly in the Northern Hemisphere, with Europe containing the largest suitable areas. By the 2050s, the total climatically co-suitable area is projected to increase by 3.1% under SSP1-2.6 and 4.3% under SSP5-8.5, while the suitable ranges of both species shift toward higher latitudes. However, A. baccarum is projected to lose suitable habitat within the current suitable range of M. persicae, indicating a possible climate-driven weakening of their geographic climatic correspondence in some regions. These findings identify broad-scale patterns of climatic co-suitability between M. persicae and A. baccarum and provide a climatic basis for prioritizing regions where the biological-control potential of A. baccarum can be evaluated further under changing environmental conditions.