【摘要】 为揭示秦岭地区耶屁步甲(Pheropsophus jessoensis Morawitz)种群的谱系地理结构,对秦岭2个地理区内25个耶屁步甲地理种群的184个个体的线粒体细胞色素氧化酶亚基I(mtCoI)基因部分序列进行了分析。在879bp个碱基中,共检测到55个变异位点,定义了67个单倍型。单倍型多样性(Hd=0.9550)较高,核苷酸多样性(Pi=0.0049)较低。东、西秦岭地区间和25个地理种群间的平均Kimura2-parameter(K2P)遗传距离都很小,介于0.0026～0.0072。分子变异(AMOVA)和嵌套进化枝谱系地理学分析(NCPA)表明,耶屁步甲的分子变异主要来源于种群内个体间,而东、西两个地区间没有明显的谱系地理结构。错配分布和中性检验分析表明,单倍型之间存在一定的地理关联,距离隔离的限制性基因流以及快速或持续的种群扩张是造成该种目前遗传特征的主要因素。对秦岭地区的耶屁步甲进行种群动态推断,最近一次扩张时间发生0.05～0.23Ma,处于更新世晚期,认为可能是第四纪冰期气候的反复变化导致了耶屁步甲现今的遗传格局。更多还原

【Abstract】 In order to understand the phylogeographic structure of Pheropsophus jessoensis Moraw- itz 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 di- versity 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 struc- ture between the eastern part and the western part of Tsinling Mountains. The NCPA showed cer- tain 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 contigu- ous range expansion. The demographic history analysis revealed that this species could have ex- perienced 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.更多还原