Fig. 4

Complete plastome structure of Cynanchum species and schematic diagrams of inter- and intraspecies variable regions showing the position of DNA markers. On the outermost circle, colored boxes show conserved chloroplast genes classified according to product function. Genes shown on the outside of the map are transcribed clockwise, while those on the inside are transcribed counter-clockwise. In the inner circles, from inside to outside, the circles indicate the location of Cw intraspecies variation, interspecies variation between Cw and Ca, and the MTPT, respectively. Black and pink signals represent the positions of InDels and SNPs, respectively. Green arrowheads indicate the location of intraspecies variation markers; 1–7 represent isv1, isv2, isv3, isv4, isv5 (Table S7), isv_cp_kasp1, and isv_cp_kasp2 (Table S8), respectively