Abstract
Cyananthus macrocalyx Franch. belongs to the genus Cyananthus in the family Campanulaceae. In this study, we sequenced and analyzed its chloroplast genome then constructed a phylogenetic tree to determine its phylogenetic position. The results show: the total length of the chloroplast genome of C. macrocalyx was 167,964 bp, with a GC content of 37.95%, and the chloroplast genome exhibited a standard quadripartite structure, consisting of a large single-copy (LSC) region (82,884 bp), a small single-copy (SSC) region (8118 bp), and a pair of inverted repeats (IRs) regions (76,962 bp). A total of 112 genes were annotated from C. macrocalyx, including 78 protein-coding genes, 30 transfer RNA (tRNA) genes, and four ribosomal RNA (rRNA) genes. Additionally, 54 simple sequence repeats (SSRs) were detected, most of which were A/T monomeric sequences. Phylogenetic analyses showed that C. macrocalyx is clustered with C. flavus, suggesting a close relationship between the two species. This study provides a valuable resource for the genetics and evolution study of the Cyananthus.