Two new species of ponerine ants from Hainan Province, China, Leptogenys hainanensis sp. nov. and L. zhoui sp. nov., are delineated and depicted based on the worker caste. Leptogenys hainanensis sp. nov. belongs to the L. leleji species group, with mandibles elongate, slender and curved, lacking a distinct masticatory margin. On the other hand, L. zhoui sp. nov. belongs to the L. crassicornis species group, distinguished by its square head, smooth body, mandibles with a dentate masticatory margin, and short antennae. A key to workers for the known species of Leptogenys in China are provided and a map is provided for the newly described species.

The species of the ant genus Brachyponera Emery, 1900 are reviewed based on the morphological characters of the worker caste. Brachyponera tianzun (Terayama, 2009) is transferred to Euponera as Euponera tianzun (Terayama, 2009), comb. nov. Four new species, B. paraarcuatasp. nov., B. xuisp. nov., B. candidasp. nov., and B. myopssp. nov., are described from China based on the worker caste. Phylogenetic trees were constructed for eight known and four new species, and genetic distances were calculated. High-resolution images of B. batak (Yamane, 2007), B. flavipes (Yamane, 2007), B. nakasujii (Yashiro et al., 2010), B. pilidorsalis (Yamane, 2007), B. wallacea (Yamane, 2007), and B. brevidorsa Xu, 1994 are provided. Keys are provided to both the eight species groups and 23 known species of the world based on the worker caste.

To elucidate the distribution patterns of ant species in the Huanglianshan National Nature Reserve, a plot‐based survey method was employed to investigate ant diversity within the reserve. A total of 209 ant species, representing 9 subfamilies and 66 genera, were collected from 38 plots spanning eight vertical gradient transects. Elevation significantly influenced ant communities within the reserve. Both ant species richness and genus richness exhibited a unimodal pattern (peaking at mid‐elevations) rather than a simple linear relationship with increasing elevation. Ordination analysis revealed significant dissimilarity between communities at low‐ and high‐elevation sites. Furthermore, the distance‐decay model confirmed that community similarity significantly decreased with increasing elevational distance. Regression analysis demonstrated a significant positive correlation between the upper elevational distribution limit of ant species and their elevational distribution breadth, indicating that species occurring at higher elevations possess wider vertical adaptation ranges. Subsequent statistical analysis of foraging and nesting habits showed that the majority of ants foraged on the ground surface and nested within the soil. Among the habitats sampled, low‐altitude tropical seasonal rainforest and coniferous‐broadleaved mixed forest harbored the highest ant species richness. In contrast, eucalyptus plantations and rubber plantations, which exhibit a higher degree of landscape homogeneity, supported significantly fewer ant species. Our data establish a foundation for further research on elevational variation and provide context for discussing key aspects of ant management and conservation in Huanglianshan National Nature Reserve.

Based on the morphological characters of the worker caste, a taxonomic study of the ant genus Polyrhachis Smith 1857 from China was conducted. Two new species, Polyrhachis (Myrma) aureodorsalis, sp. nov. and Polyrhachis (Myrmhopla) mangensis, sp. nov. are described from Fujian and Yunnan Provinces, respectively. Detailed descriptions and high-resolution images for the new species are provided. Identification keys to the known Chinese species of the subgenera Myrma Billberg 1820 and Myrmhopla Forel 1915 are presented based on the worker caste. The ecological significance and potential morphological adaptations of the new species are briefly discussed.

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.