Characterization of the complete chloroplast genome of Zanthoxylum esquirolii Levl. (Rutaceae)

Zanthoxylum esquirolii Léveillé 1914 is mainly distributed in southwest China, and its wild germplasm resources are scarce and in urgent need of conservation. In this study, we report the first complete chloroplast genome sequence of Z. esquirolii using next-generation sequencing. The circular genome is 158,390 bp in length, containing two inverted repeat (IR) regions of 27,622 bp separated by a large single copy (LSC) region of 85,580 bp and a small single copy (SSC) region of 17,566 bp. The chloroplast genome contains a total of 132 genes, including 87 protein-coding genes, 37 tRNA genes, and eight rRNA genes. The overall GC content of the chloroplast genome was 38.46%, with corresponding values in the LSC, SSC, and IR regions of 36.84%, 33.55%, and 42.51%, respectively. The phylogenetic tree revealed that Z. esquirolii Levl. formed a clade with Z. piperitum DC., Z. bungeanum Maxim., Z. simulans Hance and Z. sp. NH-2018, and had a strongly supported sister relationship with Z. bungeanum.