The Complete Chloroplast Genomes of Nine Smilacaceae Species from Hong Kong: Inferring Infra- and Inter-Familial Phylogeny

The Smilacaceae is a cosmopolitan family consisting of 200-370 described species. The family includes two widely accepted genera, namely and . Among them, the taxonomical status of has been continuously challenged. Seven and two species can be found in Hong Kong, with most of them having medicinal importance. This study aims to revisit the infra-familial and inter-familial relationships of the Smilacaceae using complete chloroplast genomes. The chloroplast genomes of the nine Smilacaceae species from Hong Kong were assembled and annotated, which had sizes of 157,885 bp to 159,007 bp; each of them was identically annotated for 132 genes, including 86 protein-coding genes, 38 transfer RNA genes, and 8 ribosomal RNA genes. The generic status of was not supported because it was nested within the clade in the phylogenetic trees, echoing previous molecular and morphological studies. We suggest delimitating the genus as a section under the genus . The results of phylogenomic analysis support the monophyly of Smilacaceae and the exclusion of from the family. This study contributes to the systematics and taxonomy of monocotyledons, authentication of medicinal Smilacaceae, and conservation of plant diversity.