The complete chloroplast genome of Heterostemma pingtaoi (Apocynaceae).

Heterostemma pingtaoi, a species endemic to Hainan Island, China, was discovered and formally described in the family Apocynaceae in 2010. However, genetic and evolutionary information on the genus Heterostemma remains poorly understood. Here, we report the complete chloroplast (cp) genome sequence of H. pingtaoi. The genome displays the typical quadripartite structure characteristic of dicotyledonous plant cp genomes, with a total length of 162,681 bp and a GC content of 38.25%. The cp genome encodes 131 genes, including 84 protein-coding genes, 8 rRNA genes, and 39 tRNA genes. Phylogenetic analysis based on the complete cp genome sequences confirmed that the genus Heterostemma forms a monophyletic group at the base of tribe Ceropegieae (Apocynaceae), with 100% bootstrap support. This study provides essential genomic resources for future taxonomic and evolutionary studies of Heterostemma species.