Figure 1. Location of Chaetodipus arenarius specimens examined for sequencing. Black-filled circles are the Northern subnetwork, open circles the Southern subnetwork, and grey-filled circles the Gulf of California subnetwork of C. arenarius. The localities with half-filled circles have specimens from all subnetworks. Rhomboids are the locations of Chaetodipus dalquesti and squares are the locations of Chaetodipus siccus. The distributions of the three species are shaded in different colours: white for C. arenarius, grey for C. dalquesti, and black for C. siccus. The specimens and geographical groups are listed in Table 1. The dashed line shows the hypothetical borders between species.