| Summary: | <i>Artemia</i> is a genus of halophilic zooplanktons comprising bisexual and parthenogenetic forms, which is an important model for investigating adaption to hypersaline ecosystems. The genus <i>Artemia</i> in China comprises four species: <i>A. sinica</i>, <i>A. tibetiana</i>, <i>A. franciscana</i> and <i>A. parthenogenetica</i>. To investigate the evolutionary relationship of bisexual and parthenogenetic <i>Artemia</i> in China, we analyzed the morphometrics and phylogenetics among twenty-two geographical populations in China. We found significant morphological differentiation across different species and strains of <i>Artemia</i> in China, which exhibited a high level of intra-population variation. We also found overlaps in morphological characteristics between populations, which may raise challenges for the classification of <i>Artemia</i> species using traditional morphological methods. <i>A. franciscana,</i> which originated from various regions in America, was generally distributed along the Chinese coastlines through multiple human introductions. Additionally, native Asian clades split into Western and Eastern Lineages during the late Miocene due to the Himalayan orogeny. Within the Western Lineage, <i>A. tibetiana</i> can be grouped into three taxon units: <i>A. tibeitiana</i>, <i>A. sorgeloosi</i> and <i>A. urmiana</i>. We also found that the distribution and genetic structure of <i>A. sinica</i> were influenced by climate oscillations during the Pleistocene, which might play a pivotal role in driving the formation of parthenogenetic strains in the Eastern Lineage. Overall, our study provides new insight into invertebrate evolution under geographical and climatic impacts in hypersaline environments.
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