Plastome Phylogeny and Taxonomy of Cinnamomum guizhouense (Lauraceae)

Abstract

Taxonomy of the genus Cinnamomum Schaeff. (Lauraceae) is difficult because of parallel evolution of morphology. Recent phylogenomic and taxonomic studies have clarified the problem and subdivided the Asian Cinnamomum into two genera, i.e., Camphora Fabr. and Cinnamomum sensu stricto. Here we sequenced and characterized the plastome of a recently described species Cinnamomum guizhouense C.Y. Deng, Zhi Yang et Y. Yang, performed a phylogenomic analysis, and also conducted a comparative analysis. The plastome of Cinnamomum guizhouense is 152,739 bp long and quadri-parted with a pair of inverted repeat regions (IR: 20,132 bp) divided by a small single copy region (SSC: 18,852 bp) and a large single copy region (LSC: 93,623 bp). The plastome possesses a total of 128 genes including 82 protein-coding genes, 36 tRNA genes, and eight rRNA genes, which is similar to most published plastomes of the core Lauraceae group. The plastome of Cinnamomum guizhouense displays higher similarity to Camphora than Cinnamomum. Our phylogenomic result suggests that Cinnamomum guizhouense belongs to the Camphora clade. As a result, we propose a new combination, i.e. Camphora guizhouensis (C.Y. Deng, Zhi Yang et Y. Yang) Zhi Yang et Y.Yang, comb. nov.