Figure 1. Map of the distribution of Vandiemenella viatica on Kangaroo Island, South Australia.

Sampling sites (approximately positioned) for the five populations of three chromosomal races are colour-coded by population: viatica17-east (light red), viatica17-south (dark red), viatica19 (green), P24(XY)-east (dark blue), P24(XY)-north (light blue). Hybrid populations, as determined by STRUCTURE analysis, are white-filled squares. Below is the evolutionary sequence of chromosomal arrangements which gave rise to the three races, according to White et al. [26]. Adapted with permission from Kawakami et al. [19].