show Abstracthide AbstractIn this study, we aimed to determine the origin(s) and the number of introduction events of C. formosanus out of eastern Asia and into the US. We sampled this species in both its native and introduced ranges and used double digest restriction-site associated DNA sequencing (ddRADseq48) to obtain markers of high resolution (i.e., single-nucleotide polymorphisms, or SNPs). We first conducted population structure and phylogenetic analyses of the global C. formosanus population to assess genetic structure within its native range and determine the genetic relationship between native and introduced populations. Second, we used approximate Bayesian computation (ABC) to decipher its worldwide routes of invasion. Finally, we investigated introduction-induced effects on population demography, such as population bottlenecks, expansions, migration and admixture, to assess the consequences of the invasion on the global genetic patterns of this species.