Southwestern Australia has been recognized as a biodiversity hotspot of global significance, and it is particularly well known for its considerable diversity of flowering plant species. Questions of interest are how this region became so diverse and whether its fauna show similarly diverse patterns of speciation. Here we have carried out a phylogeographic study of trapdoor spiders (Migidae: Moggridgea), a presumed Gondwanan lineage found in wet forest localities across southwestern Australia. Phylogenetic, molecular clock and population genetic analyses of mitochondrial (mtDNA) COI gene and ITS rRNA (internal transcribed spacer) data revealed considerable phylogeographic structuring of Moggridgea populations, with evidence for long-term (> 3 million years) isolation of at least nine populations in different geographic locations, including upland regions of the Stirling and Porongurup Ranges. High levels of mtDNA divergence and no evidence of recent mitochondrial gene flow among valley populations of the Stirling Range suggest that individual valleys have acted as refugia for the spiders throughout the Pleistocene. Our findings support the hypothesis that climate change, particularly the aridification of Australia after the late Miocene, and the topography of the landscape, which allowed persistence of moist habitats, have been major drivers of speciation in southwestern Australia.

Moggridgea_COI_nexA text file containing the nexus input file of COI sequences from 103 Moggridgea spiders, including 95 Moggridgea tingle from south-western Australia (T numbers), 5 Moggridgea species from Africa and 3 Moggridgea australis from Kangaroo Island, South Australia. This nexus file was used to produce COI phylogenetic trees presented in the Cooper et al. (2011) Molecular Ecology paper.Moggridgea_COI_reduced_nexA text file containing the nexus input file of COI sequences from 47 Moggridgea spiders, including 46 Moggridgea tingle from south-western Australia (T numbers), and one Moggridgea australis from Kangaroo Island, South Australia. This nexus file contains a reduced COI dataset after removal of identical haplotype sequences and was used to produce COI phylogenetic trees presented in the Cooper et al. (2011) Molecular Ecology paper.Moggridgea_ITS_nexThis file is a text file containing 53 ITS rRNA sequences from Moggridgea tingle (T numbers), 3 from Moggridgea australis (Mog1-3) and 3 African Moggridgea (MY numbers). It was used to produce phylogenetic trees given in the Cooper et al. (2011) Molecular Ecology paper.