Abstract: Objective　To conduct molecular identification and population genetic analysis of Pomacea based on mitochondrial cytochrome c oxidase subunit Ⅰ (COI) gene sequence in Dali Bai Autonomous Prefecture, so as to provide the theoretical evidence for the scientific management of the invasive Pomacea.  Methods　Pomacea samples were collected during field surveys of Pomace spp. in Dali Bai Autonomous Prefecture from March 2023 to December 2024. Genomic DNA was extracted from the foot muscle tissue of Pomacea samples for PCR amplification and sequencing. The sequences were subjected to haplotype analysis, sequence similarity, and phylogenetic analysis using the software MEGA 11, DnaSP 5.1, and Geneious Prime 2024, respectively. The haplotype network relationship diagram was plotted with the software PopART to unravel the population genetic structure of Pomacea spp., and genetic diversity parameters and molecular variance analyses were conducted using the software DnaSP 5.1 and Arlequin 3.5. The population genetic differentiation index (Fst) and inter⁃population gene flow (Nm) were calculated, and the historical population dynamics of the Pomacea spp. were inferred in Dali Bai Autonomous Prefecture based on neutrality tests and mismatch analysis.  Results　A total of 379 gene sequences from nine geographical populations of Pomacea spp. were obtained in this study. Haplotype analysis revealed nine haplotypes, including hap1, hap4, hap11, hap18, hap20, hap21, hap22, hap 23 and hap24, and both sequence similarity and phylogenetic analyses indicated that these nine haplotypes were clustered into three distinct groups, and were identified as P. canaliculate (hap1, hap4 and hap11), P. occulta (hap18, hap20, hap21, hap22, and hap23), and P. maculata (hap24). P. canaliculata was detected across all nine geographical populations in Dali Bai Autonomous Prefecture, with a high overall genetic diversity, and the inter⁃population genetic variation (71.20%) was much higher than intra⁃population genetic variation (19.50%), with Fst of 0.712, and Nm of 0.351. P. occulta had unique haplotypes (hap20 to hap23), which contained few gene sequences and had a relatively low overall genetic diversity, and the intra⁃population genetic variation (80.50%) was much higher than inter⁃population genetic variation (16.45%), with Fst of 0.165, and Nm of 1.515. Neutrality tests and mismatch analysis showed that the overall Tajima's D value (4.564), Fu and Li's F* value (3.866), and Fu and Li's D* value (2.163) of P. canaliculata populations were all positive and exhibited significant differences in Dali Bai Autonomous Prefecture (all P values < 0.05), with two distinct peaks generated by mismatch distributions. In contrast, the overall Tajima's D value (-1.574), Fu and Li's F* value (-0.889), and Fu and Li's D* value (-0.328) of P. occulta populations were all negative, with no significant differences detected (all P values > 0.05), and the mismatch distribution produced only a single main peak. Conclusions　This is the first report to unravel P. canaliculata, P. occulta, and P. maculata in Pomacea spp. populations in Dali Bai Autonomous Prefecture, and P. canaliculata is the dominant species in the majority of geographical Pomacea spp. populations, with a high genetic diversity and high inter⁃population genetic differentiations. The P. canaliculata population conforms to the neutral evolution theory and the population size may be in an equilibrium or contraction state. In contrast, P. occulta has a relatively low genetic diversity and a low inter⁃population genetic differentiation, which may have recently experienced a population expansion event.  

Key words: Pomacea spp., Pomacea canaliculata, Pomacea occulta, Pomacea maculata, Phylogenetic analysis, Genetic diversity, Molecular variance, Dali Bai Autonomous Prefecture

摘要： 目的　基于线粒体细胞色素c氧化酶亚基Ⅰ（cytochrome c oxidase subunit Ⅰ，COI）基因序列对大理白族自治州（大理州）福寿螺进行分子鉴定和种群遗传学分析，以期为入侵福寿螺的科学防控与治理提供理论依据。方法 　2023年3月至2024年12月在大理州福寿螺现场调查中采集福寿螺样本，取其足部肌肉组织提取基因组DNA并进行PCR扩增及测序。使用MEGA 11、DnaSP v5.1软件及Geneious Prime 2024软件对序列分别进行单倍型分析、序列相似度与系统发育学分析；采用PopART软件绘制单倍型网络关系图以揭示种群遗传结构，并用DnaSP v5.1软件与Arlequin 3.5软件进行遗传多样性参数与分子变异分析，计算种群遗传分化指数（Fst）和种群间基因交流（Nm）；最后，基于中性检验和错配分析推测大理州福寿螺群体历史动态。结果　本研究共获得来自大理州9个福寿螺地理种群的379条序列，单倍型分析检出9个单倍型（hap1、hap4、hap11、hap18、hap20 ~ hap24）。序列相似性与系统发育学分析共同表明，上述9个单倍型聚类为3个不同的组且分别被鉴定为小管福寿螺（hap1、hap4、hap11）、隐秘福寿螺（hap18、hap20 ~ 23）和斑点福寿螺（hap24）。大理州9个地理种群均有小管福寿螺分布，总体遗传多样性较高，各地理种群间遗传变异（71.20%）远大于种群内遗传变异（19.50%），Fst为0.712，Nm为0.351；隐秘福寿螺发现个别特有单倍型（hap20 ~ hap23），但其包含序列数极少，总体遗传多样性相对较低，各地理种群内遗传变异（80.50%）远大于种群间遗传变异（16.45%），Fst为0.165, Nm为1.515。中性检验和错配分析结果表明，大理州小管福寿螺种群总体Tajima’s D值（4.564）、Fu和Li’s F*值（3.866）、Fu和Li’s D*值（2.163）均为正值且差异均具有统计学意义（P均< 0.05），错配分布产生了2个不同的峰；隐秘福寿螺种群总体Tajima’s D值（-1.574）、Fu和Li’s F*值（-0.889）、Fu和Li’s D*值（-0.328）均为负值但差异均无统计学意义（P均> 0.05），错配分布仅产生了单一主峰。结论 　本研究首次探明大理州福寿螺种群有小管福寿螺、隐秘福寿螺、斑点福寿螺3个物种。其中小管福寿螺为多数地理种群的优势种，遗传多样性较高，种群间存在高度遗传分化；该种群符合中性进化理论，群体大小可能处于平衡或收缩状态。隐秘福寿螺种群遗传多样性及种群间遗传分化相对较低，但近期可能经历过种群扩张事件。

关键词: 福寿螺, 小管福寿螺, 隐秘福寿螺, 斑点福寿螺, 系统发育分析, 遗传多样性, 分子变异分析, 大理白族自治州