Geographic distribution of ITS2 rDNA haplotypes detected in this study: (A) Sanguina nivaloides, (B) Sanguina aurantia. Each haplotype network was constructed by a statistical parsimony method with a 95% connection limit. The Sanguina nivaloides network includes haplotypes from polar regions (Antarctica, Svalbard) and alpine regions in Europe (Austria, Italy, Norway, Slovakia, Slovenia, Switzerland), North America (Colorado) and South America (Argentina). The Sanguina aurantia network includes haplotypes from Svalbard. Each ball represents a haplotype (i.e. in this study's field samples, which have identical ITS2 sequences). The size of the ball is proportional to the number of specimens sampled, which belong to that specific haplotype. The colour represents a country of sampling. Lines connect each haplotype with its most similar relative. Open dots represent mutation steps between haplotypes, one dot indicates a change of one base pair.