The complete chloroplast genome and phylogenetic analysis of Cardamine circaeoides Hook. f. et Thoms., 1861 (Brassicaceae)

A species of Cardamine circaeoides Hook. f. et Thoms., 1861, which belongs to the Cardamine family (Brassicaceae), is an endemic species of the Wuling Mountains in Hunan and Hubei Provinces of China. Since there are many morphologically related species of C. circaeoides, the chloroplast (cp) genome characteristics of C. circaeoides were analyzed in order to explore the phylogenetic relationship between it and the closely related species. A cp genome totaling 154,838 base pairs exhibited a typical quadripartite structure with a pair of IRs (inverted repeats; 26,493 base pairs) separated by a small single-copy region of 17,938 base pairs and a large single-copy region of 83,914 base pairs. A total of 130 genes were found in the cp genome, including 85 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. There were 36.21%, 33.96%, 29.09%, and 42.35% GC content in the entire cp genome, LSC region, SSC region, and IR region, respectively. According to phylogenetic analysis, C. circaeoides is evolutionarily closer to Cardamine hupingshanensis.