Results of multiple analyses using the individual-based Bayesian clustering program structure. Analyses were conducted with different values of K (the number of hypothetical populations the program should sort individuals into). Plots are shown for K=2, 3, 4, 5 and 8 (see supplementary data for others), each vertical bar in the plot represents one individual and the colouring of the bars represents the posterior probability of that individual belonging to each of the K hypothetical populations based on Hardy-Weinberg equilibrium and linkage. At the bottom of the plots, the mitochondrial haplotype group of that individual beetle is shown (CRB-G, CRB-S and CRB-PNG). The OrNV infection status also showed for each individual.