The complete mitochondrial genome of Leuciscus chuanchicus (Kessler, 1876) (Cypriniformes: Cyprinidae).

Leuciscus chuanchicus, a fish distributed in the upstream regions of the Yellow River, was the focus of this study, which aimed to depict the structural characteristics of its mitochondrial genome and clarify its phylogenetic relationship within Leuciscus. High-throughput sequencing technology was used to obtain the complete mitochondrial genome of L. chuanchicus. Additionally, a phylogenetic tree of L. chuanchicus and seven other Leuciscus species was constructed based on the mitochondrial genome using the maximum-likelihood (ML) method. The results revealed that the L. chuanchicus mitochondrial genome spans 16,602 bp and contains 13 protein-coding genes, 22 tRNA genes, two rRNA genes, and a non-coding D-loop region. The mitochondrial genome exhibited the highest A + T content (53.7%). ATG was the most common start codon in the protein-coding genes, except for the COX1 gene, which started with GTG. The phylogenetic tree constructed using the ML method showed that L. chuanchicus was closely related to L. waleckii walechii. This study adds valuable data on the L. chuanchicus mitochondrial genome, aiding in the understanding of the phylogenetic relationships within Leuciscus. By constructing phylogenetic trees, the evolutionary relationships of L. chuanchicus within Leuciscus were discussed, providing essential data for revising the classification of this genus. Therefore, it also offers a theoretical basis and essential information for biodiversity conservation and germplasm resource assessment of L. chuanchicus.