In order to understand the phylogeny of Rotaria sordida in China and the world, and to clarify the driving factors of the genetic differentiation of bdelloid rotifers, R. sordida samples were collected from 12 cities in 10 provinces of China, and 32 COⅠ gene sequences were obtained. Moreover, 47 COⅠ gene sequences from Europe and Oceania in the GenBank database were downloaded, and the Bayesian phylogenetic tree was constructed at China and global scales, respectively. The results showed that the COⅠ gene sequences of R. sordida in China were divided into two taxonomic clusters, and their phylogenetic relationships were not only affected by geographical location, but also related to habitat types. At global level, all sequences were also divided into two clusters, and some sequences in China were clustered with sequences from Europe and Oceania. The bdelloids with the same habitat type in the two clusters had high homology. It was speculated that the phylogeny of bdelloid rotifers was driven by geographic distribution and habitat heterogeneity. Genetic diversity analysis based on the Generalized Mixed Yule Coalescent model (GMYC) showed that 22 haplotypes and 12 cryptic species were identified from the COⅠ sequence of R. sordida in China; 45 haplotypes and 28 cryptic species were identified from the global COⅠ sequence. This indicated the high hidden diversity in R. sordida species complexes. Therefore, habitat heterogeneity played an important role in cryptic species differentiation of R. sordida. This study preliminarily explained the phylogenetic relationship and genetic diversity of R. sordida in China and the world. Furthermore, this study supplemented the COⅠ gene database of bdelloid rotifers in China, and provided basic data for lineage biogeographic studies in the future. 

为了解蛭态轮虫广布种污轮虫(Rotaria sordida)在中国和全球的系统发育关系, 明确蛭态轮虫遗传分化的驱动因素, 采集中国10省 12市的污轮虫样品, 获得COⅠ基因有效序列32条, 同时下载GenBank数据库中来自欧洲和大洋洲污轮虫的47条序列, 分别构建中国和全球两个地理尺度的贝叶斯系统发育树。结果显示, 中国污轮虫COⅠ序列分为两个分类簇, 其系统发育关系不仅受到地理位置的影响, 还与生境类型有关; 全球污轮虫COⅠ序列由两个分类簇构成, 分类簇内部分中国序列与欧洲和大洋洲序列形成同一分支。生境类型相同的污轮虫具有较高的同源性, 推测污轮虫系统发育受到地理分布和生境异质性的共同驱动。基于广义混合Yule溯祖模型的遗传多样性分析结果表明, 中国污轮虫COⅠ序列鉴定出22个单倍型和12个分子隐种; 全球污轮虫COⅠ序列鉴定出45个单倍型和28个分子隐种, 证明污轮虫形态学物种内具有较高的隐藏多样性, 推测生境异质性对隐种的发生具有重要作用。研究结果初步阐述了中国及全球污轮虫的系统发育关系和遗传多样性, 补充了中国陆生生境蛭态轮虫的COⅠ基因数据库, 可为中国和世界谱系的生物地理学研究提供基础数据。