Morphological and molecular assessment of the Diplodactylus savagei species complex in the Pilbara region, Western Australia, with a description of a new species

The gecko Diplodactylus savagei is restricted to the rocky Pilbara and Ashburton regions of Western Australia. Recent collections have enabled a reappraisal of morphological and genetic diversity within the taxon. Analysis of 1200 base pairs of the mtDNA gene ND2 and surrounding tRNA found strong support for three lineages within D. savagei: an eastern clade (which includes the type location of D. savagei from Marble Bar), a southern clade and a north-central clade. The eastern and southern clades did not differ in morphology or dorsal pattern. Although there are several subtle differences in morphological characters between the eastern and southern clades compared to the north-central form, there were clear differences in dorsal pattern with the north-central forms having finer, widely-scattered spots, a pale dorsal border to the loreal stripe and a gradual transition between the dorsal and ventral colouration. We describe the north-central form as a new species, D. galaxias sp. nov., based on the distinctiveness of its colour pattern, subtle morphological differences, mtDNA divergence and maintenance of these differences at the edge of the western Hamersley Range where the north-central and southern clades come into contact.