Identification and invasive potential of Opuntia humifusa complex in China: Insights from morphology, plastid genomics, and niche modeling

The genus Opuntia contains a handful of widespread invasive species, posing significant ecological threats worldwide. In China, the first records of two populations from the O. humifusa complex have become invasive and continue to expand recently. The expansion of these populations and the complexities of accurately identifying them within the complex highlight the urgent need for comprehensive study. Accurate species identification, early detection, and potential distribution modeling are considered as crucial and cost-effective measures to prevent plant invasions, significantly reducing the resources required for formulating effective management strategies. Here, we employ phylogeny, plastid genomics, and MaxEnt modeling to address the species identification and spread potential to enhance our understanding of the ecological implications of these new invasive populations and O. humifusa complex in China. Morphological and molecular analyses indicate that both populations are identified as O. humifusa within the complex. ArcGIS and the MaxEnt model predict potential invasion areas of O. humifusa complex within central and eastern China, with climatic change scenarios suggesting an overall increase in suitable habitats. Key environmental factors include precipitation of driest quarter, max temperature of warmest month, and solar radiation, collectively shaping the complex’s potential distribution. This study enhances our understanding of the O. humifusa complex's ecological and invasive dynamics in China, offering invaluable insights for ecological management and biodiversity preservation. Through comprehensive research, we provide a basis for proactive measures against the complex's expansion. • A new invasive species from Opuntia humifusa complex was discovered in China. • Morphological and molecular analyses confirm it as Opuntia mesacantha . • High genetic diversity suggests strong invasion potential in O. mesacantha . • Ecological model forecasts expanding invasion rage of O. humifusa complex in China. • Distribution shaped by driest quarter precipitation and max warm month temperature.