Potential distribution of the invasive loblolly pine mealybug, Oracella acuta (Hemiptera: Pseudococcidae), in Asia under future climate change scenarios

Oracella acuta is a significant invasive insect pest in China, which has already caused severe damage to host pines. It is expected that this pest may invade other regions of Asia. This research explores the projected effects of climate change on the future distribution of O. acuta in Asia. To anticipate threats and prioritize management strategies to control O. acuta, we examined the potential distribution of O. acuta under current and future climate scenarios based on CLIMEX models. These models were calibrated using the physiological tolerance thresholds for this species, and A1B and A2 scenarios for 2030 and 2070 under a CSIRO-Mk 3.0 Global Climate Model were used to predict future distribution. The results suggest that O. acuta has the ability to establish in most countries of Southern Asia, such as China, Vietnam, Laos, Myanmar, Bhutan, Bangladesh, Philippines, Sri Lanka, and India. Both scenarios showed that the species is predicted to expand its range northwards but retract in the southern edge. The A1B scenario projected a wider spread of O. acuta than the A2 scenario. Despite the uncertainties inherent to climate models and that it was not possible to integrate all parameters into the model and some assumptions had to be made, our results indicate that heat and drought stress may have significant impacts on the species distribution, especially in southern regions of Asia in the future.