Shaobo Wang, Mengjiao Han, Yanlong Tang, Yanlong Zhang, Xiaoyi Wang, Ke Wei
Cyanopterus ninghais Wang (Hymenoptera: Braconidae), a highly specialized parasitoid of Monochamus alternatus Hope (Coleoptera: Cerambycidae) larvae, is a pivotal natural enemy with substantial potential for the management of pine wilt disease (PWD). Prior to the field release of the parasitoid, accurate delineation of suitable habitats is essential for ensuring biocontrol efficacy. Since habitat suitability is constrained not only by climate but also by host distribution, climate-only models lack sufficient precision to reliably assess colonization potential. Therefore, we employed the MaxEnt model to predict the potential habitats of C. ninghais in China by integrating occurrences, climate, and the distributions of its sole host, M. alternatus, to quantify the contributions of climate and host availability in shaping its habitat suitability. Results showed that mean diurnal temperature range (Bio2) and precipitation seasonality (Bio15) were the dominant climatic factors influencing habitat suitability, with suitable areas primarily concentrated in warm and humid regions of southeastern China. Adding host distribution expanded the highly suitable areas for C. ninghais that closely overlapped with the distribution of M. alternatus, indicating that host resources substantially enhance the establishment capacity of the parasitoid. This study developed a dual-factor (climate-host) driven habitat suitability model for the targeted release of the parasitoid and the strategic deployment of PWD biological control. These findings optimize biological control strategies against PWD and improve the establishment success and biocontrol efficiency of C. ninghais, while offering a modeling framework for assessing parasitoid-pest interactions and range expansion under future climate change.