The complete chloroplast genome and phylogenetic relationship of Apocynum pictum (Apocynaceae), a Central Asian shrub and second-class national protected species of western China

•We reported the complete chloroplast genome of Apocynum pictum, a protected shrub.•Two genes possibly involved in ecological adaptation were under positive selection.•Genomic structures were highly conserved among nine species of Apocynaceae.•Phylogenetic analyses supported a clade of A. venetum and A. pictum.