We compiled all available occurrence data for the species in Europe from the GBIF database (Dooley 2002), classical and online publications, a survey among European arachnologists, and by own field studies. In total, our distribution dataset comprises 228 records. Due to its notoriety as a venomous species, the occurrence and expansion of C. punctorium is quite well documented and new occurrences are usually accompanied by media coverage (Muster et al. 2008). Our approach thus probably allowed a reasonably accurate approximation of the species' contemporary range. To identify ecological differences between old and recently established populations, we distinguished native and expanding populations. Seventy‐three occurrences could be identified as native, 136 as expanding, while 19 occurrences had uncertain status. To distinguish native and expanding populations, we performed two separate analyses. A first analysis was performed with a reduced dataset of populations, for which we could acquire genotyping results (see Molecular analysis). Population subdivision was based on genetic differentiation. Based on these results, we performed a second analysis, assigning populations to the native and expanding groups based on proximity to genotyped populations and considering the species' documented expansion. Expanding sites were assigned to those, where a recent expansion of the species has been reported, or where it was only recently discovered. The results of both analyses were compared, to ensure a proper population assignment.