2.1 | Sample collection
We collected 108 Sinocyclocheilus individuals from 24 populations in the central Yunnan Basin (Fig. 1) . The caudal fin or muscle tissue from each individual was preserved in 95% ethanol for DNA extraction. The individuals were stored in 10% methanol to facilitate taxonomic identification and deposited in the Kunming Institute of Zoology, Chinese Academy of Sciences (KIZ). Data from additional samples was sourced from the National Center of Biotechnology Information (NCBI). Information associated with each sample is provided inTable 1 .
Sinocyclocheilus fishes are listed under Class II of the nationally protected animals classification in China. All specimens used in this study were collected with the permission of the relevant animal protection government departments in China. The study also complied with the current laws on animal research in China. and no more than five individuals were collected from each population.