Geographic distribution of COI haplotypes of E. sinensis and E. japonica in the studied region of Europe, based on newly-generated and publicly-available sequence data A the WE (Weser River), EL (Elbe River) and LA (Laascher Lake) populations were sampled by Hänfling et al. (2002) and the BE (Belgium) population was collected in 1998 and used in this study B the NL (Netherlands), RH (Rhine River), PL (Poland), OD (Oder River) and SE (Sweden) samples were publicly available and previously synthesised by Hayer et al. (2019). The BE, EI, WE, EL, KF, AU and PL populations were sampled in this study and are detailed in Table 1 C all sequences were newly generated in this study and sample information is available in Table 1. Haplotype names correspond to Hayer et al. (2019).