Species delimitation methods facilitated the identification of cryptic species within the broadly distributed species in Homoeocerus (Tliponius) (Insecta: Hemiptera: Coreidae)

Integrative species delimitation based on multi-data including morphology and molecular biology can accurately identify species and rapidly detect cryptic species. Comprehensive sampling is crucial for the accuracy of species delimitation in widely distributed species. Here, we focused on the Tliponius subgenus widely distributed in China and selected extensive samples covering the species' distribution ranges. Studies were conducted using species delimitation and population genetics methods based on morphological, mitochondrial gene, and nuclear SNP data. A cryptic species from Yunnan was discovered and named Homoeocerus (Tliponius) dianensis Liang & Bu sp. nov. Genetic distance results revealed a significant genetic distance gap between the maximum intraspecific genetic distance and the minimum interspecific genetic distance within this subgenus. Phylogenetic analyses showed that Tliponius is divided into two clades (Clade A: (H. dilatatus + (H. marginellus + (H. unipunctatus + H. dianensis sp. nov.))); Clade B: (H. yunnanensis + (H. laevilineus + H. marginiventris))), and the two clades diverged approximately 27.06 million years ago. This study provided insights for species delimitation research based on multi-type data and involving widely distributed species.