Abstract: 【Aim】 The objective of this study is to investigate the genetic diversity and genetic differentiation of geographical populations of the stick tea thrip, Dendrothrips minowai, in South China based on the combined sequence of mtDNA COⅠ and COⅡ. 【Methods】 The genetic diversity, genetic differentiation, gene flow, analysis of molecular variance and correlations between geographical distance and genetic distance of eight geographical populations of D. minowai in South China were analyzed by using software MEGA 6.0, DnaSP 5.10, Arlequin 3.5.2.2, etc., and their demographic history was deduced. 【Results】 Both the mtDNA COⅠ and COⅡ sequences of D. minowai have obvious AT bias, and the combined sequence of COⅠ and COⅡ is 1 146 bp in length with 22 haplotypes. The total population of D. minowai in South China had a high level of genetic diversity, high haplotype diversity (Hd=0.924) and low nucleotide diversity (π=0.00600). The total population of the eight geographical populations had a high degree of genetic differentiation (F_ST=0.84830) and low level of gene communication (Nm=0.040). Significant differentiation might have occurred among different geographical populations due to genetic drift. AMOVA analysis showed that the genetic variation mainly came from the populations among groups (F_CT=0.84922). Mantel test indicated that the geographical distance was significantly positively correlated with the genetic distance (r=0.5029, P<0.01). Neutrality test results revealed that the geographical populations of D. minowai  except the two geographical populations in Yunnan Province have experienced population expansion recently. 【Conclusion】 Geographical populations of D. minowai in South China have a high level of genetic diversity, a high degree of genetic differentiation and a low level of gene communication. Geographical distance might be one of the key factors affecting genetic differentiation among geographical populations of D. minowai．

Key words: Dendrothrips minowai, geographical population, genetic diversity, genetic differentiation, geographical distance