Historical biogeography and environmental filtering jointly shape ant diversity in Huanglianshan National Nature Reserve, China

Ants are key indicators of ecological health, yet the factors shaping their diversity in Yunnan's montane transitional zones remain poorly understood. This study examines how historical biogeography and contemporary environmental filtering jointly drive ant diversity patterns in the Huanglianshan National Nature Reserve, China. We systematically surveyed ant assemblages across an elevational gradient (320-2637 m), recording 209 species from 66 genera and 9 subfamilies. Multi-scale biogeographical analyses revealed that all recorded species occur in the Oriental realm, with 50.72% also distributed in the Palearctic realm, reflecting the region's transitional faunal affinities. Within China, the fauna is most closely allied to the Southwest, South China, and Central China regions. Environmental analyses across eight typical ecological zones of Yunnan indicated that ant species richness increases with habitat area, rainfall, and humidity, but declines with elevation and latitude. These findings support a "historical-ecological" framework wherein the regional species pool, shaped by biogeographic history, is filtered by contemporary environmental gradients. Our results provide a scientific basis for biodiversity conservation in Yunnan's montane ecosystems and contribute to understanding diversity maintenance mechanisms in tropical-subtropical transition zones.