Abstract: In order to understand the phylogeographic structure of Pheropsophus jessoensis Morawitz in the Tsinling Mountains, a fragment with 789 bp from the mtCoI gene was sequenced for the 184 P. jessoensis individuals from 25 geographical populations belonging to two geographic areas. A total of 55 polymorphic sites were found, and 67 haplotypes were identified. The haplotype diversity was high (H_d=0.9550), while the nucleotide diversity was relatively low (P_i=0.0049). The Kimura 2-parameter (K2P) genetic distance of the P. jessoensis between west Tsinling population and east Tsinling population or among the 25 populations was small, with the values ranged from 0.0026 to 0.0072. The analysis of molecular variance (AMOVA) and the nested clade phylogeographical analysis (NCPA) revealed the significant genetic subdivision among the individuals within populations, but there existed no remarkable phylogeographic structure between the eastern part and the western part of Tsinling Mountains. The NCPA showed certain geographical association of haplotypes. The results from mismatch distribution and neutrality tests suggested that the present complex genetic pattern of P. jessoensis in Tsinling Mountains was resulted from the restricted gene flow with isolation by distance, and from the sudden or contiguous range expansion. The demographic history analysis revealed that this species could have experienced a relatively recent population expansion occurring in the later Pleistocene (0.05-0.23 Ma). The climatic oscillations during this period might have affected the geographical isolation and genetic differentiation of P. jessoensis in this area.

Key words: aquic brown soil, soil organic nitrogen form, long-term fertilization.