ReadMe This document gives a short description of the data used in the manuscript:'Unequal contribution of native South African phylogeographic lineages to the invasion of the African clawed frog, Xenopus laevis, in Europe' C. De Busschere, J. Courant, A. Herrel, R. Rebelo, D. Rödder, G.J.Measey, T. Backeljau contact:charlotte.debusschere@gmail.com 16S.nexus Nexus file generated by DnaSP Ver. 5.10.01 containing all the 16S sequences used in the manuscript. See file 'Online resource 1' for Genbank accesssion numbers and full sample information. cytb.fas Fasta file containing all the cytb sequences used in the manuscript. See file 'Online resource 1' for Genbank accesssion numbers and full sample information. prmt6.nex Nexus file generated by DnaSP Ver. 5.10.01 containing all the phased prmt6 sequences used in the manuscript. Haplotype phases were reconstructed from the raw data using the algorithm PHASE 2.1 implemented in DNAsp Ver. 5.10.01. See file 'Online resource 1' for Genbank accesssion numbers and full sample information. Mastl.nex Nexus file generated by DnaSP Ver. 5.10.01 containing all the phased Mastl sequences used in the manuscript. Haplotype phases were reconstructed from the raw data using the algorithm PHASE 2.1 implemented in DNAsp Ver. 5.10.01. See file 'Online resource 1' for Genbank accesssion numbers and full sample information. AR.nex Nexus file generated by DnaSP Ver. 5.10.01 containing all the phased AR sequences used in the manuscript. Haplotype phases were reconstructed from the raw data using the algorithm PHASE 2.1 implemented in DNAsp Ver. 5.10.01. See file 'Online resource 1' for Genbank accesssion numbers and full sample information. Online resource 1 Table. 1 Overview of sample, locality and allelic information. GenBank accession numbers listed in bold correspond to sequences of previous studies. Online resource 2-5 Fig. MP and BI tree of unique concatenated Cytb-16S haplotypes Table. PCR cycle conditions Table. Pairwise Population Fst values based on pairwise nucleotide differences for 16S. Table. Pairwise Population Fst values based on nuclear allele frequencies.