Figure 1.

Sampling sites of B. dorsalis s.s. and B. papayae in this study. Seventeen fruit fly populations were collected from the top of Southern Thailand to the end of the Malay Peninsula (West Malaysia). Information for each sample is described in Table 1. The Isthmus of Kra (connecting zone between yellow and green areas) is the putative transition zone between Bactrocera dorsalis s.s. (yellow area) and B. papayae (green area) distribution [7,11]. Intra- and inter-specific differences (F_ST) among nearby populations are reported. The red line represents intra-specific difference (pairwise F_ST between populations with the same morphological form) while the green line represents inter-specific difference (pairwise F_ST between populations with different morphological forms). An asterisk (*) indicates a non-significant F_ST value. Rectangular boxes detail the designated locations (by arrow) where either sympatric or temporal populations were collected.