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Spodoptera frugiperda, the fall armyworm (FAW), is a widespread and polyphagous crop pest, causing serious crop yield losses worldwide, especially maize and other cereals. Biological control (biocontrol) is considered as the generally safer and more environmentally benign strategies compared to chemical insecticides in managing FAW. Chelonus insularis and Eiphosoma laphygmae are two promising classical biocontrol parasitoids against FAW. However, the optimal control areas for FAW with the two parasitoids in its invasive ranges remain unclear. This study is first time to integrate species distribution models and hotspot analysis to estimate the optimal areas for controlling FAW with these two parasitoids worldwide. Key variables influencing distribution include human influence index, temperature, and precipitation. The optimal control areas of FAW with C. insularis and E. laphygmae are in most of sub-Saharan Africa, Mediterranean regions, eastern, southern, and southeastern Asia, and Oceania. These areas are expected to expand to high-latitude areas under changing climatic conditions. Niche comparisons indicated that the FAW and C. insularis niches were closely aligned. Chelonus insularis and E. laphygmae are potentially effective against FAW in Africa, Asia, and Oceania. Our findings offer insights into the strategic use of the two parasitoids against FAW worldwide.

The boll weevil, Anthonomus grandis Boheman (Coleoptera: Curculionidae), is an invasive alien species that can damage cotton plants and cause huge economic losses in the cotton industry. Currently, A. grandis is mainly distributed in the American continent. However, few studies have indicated the distribution and modification of its suitable global habitats after undergoing climate change. Based on the 339 distribution records of A. grandis and eight bioclimatic variables, we used the optimal MaxEnt model to predict the potential global distribution of A. grandis under the current (1970–2000) and future climatic scenarios (SSP5-8.5). The annual mean temperature (bio1) and isothermality (bio3) were the two most important bioclimatic variables, which indicates that the survival of A. grandis is extremely sensitive to temperature fluctuations. Under the current scenario, the highly suitable habitats were mainly distributed in America (the USA, Mexico, Brazil, Argentina, Paraguay, and Uruguay), Africa (South Africa, Ethiopia, and Mozambique), Asia (Pakistan, India, Thailand, Burma, and China), and Oceania (Australia). In future scenarios (SSP5-8.5), the potential suitable global habitats reached the highest level in America, Africa, Asia, and Oceania in the 2090s. Our study provides a meaningful reference for researchers, quarantine officers, and governments to devise suitable management control strategies for A. grandis.