11: Median-joining network of mtCOI haplotypes. Shaded circles represent haplotypes, haplotype names refer to Table 1. Shading coding indicates the species of specimens carrying a particular haplotype; diameter is relative to the number of specimens carrying a particular haplotype. Lines between haplotypes represent genetic distances between haplotypes; branch length is relative to distance, very long branches are shown with breaks. Small black circles represent median vectors. 12: View of the sampling site of D. nigrescens at the Furka-Paß, Switzerland, showing the small, spring-fed, first order tributary of the Mutt. 13: D. nigrescens, habitus of the coal-black male.