Phylogeography, species delimitation and population structure of a Western Australian short-range endemic mite harvestman (Arachnida: Opiliones: Pettalidae: Karripurcellia)

Abstract

The mite harvestmen of the genusKarripurcelliaGiribet, 2003 are endemic to the tall, wet eucalypt forests of south-western Western Australia, a region known as a hotspot for biodiversity. Currently, there are two accepted species,K.peckorumGiribet, 2003 andK.sierwaldaeGiribet, 2003, both with type localities within the Warren National Park. We obtained 65COImtDNA sequences from across the entire distributional range of the genus. These sequences, falling into two to three geographically separate groups, probably correspond to two species. Morphologically, all of the studied specimens correspond toK.peckorum, suggesting cryptic speciation within that species. A few common haplotypes occur in more than one population, but most haplotypes are confined to a single population. As a result, populations are genetically differentiated and gene flow after initial colonization appears to be very limited or completely lacking. Our study provides another example of short-range endemism in an invertebrate from the south-western mesic biome.