Spots before the eyes: revision of the saxicoline geckos of the Gehyra punctata (Squamata: Gekkonidae) species complex in the Pilbara region of Western Australia

WA Museum Records and Supplements | Updated 6 years ago

ABSTRACT – The Gehyra punctata species complex in the Pilbara and surrounding regions of Western Australia has long been known for its confused taxonomy. Recent collections in the region have enabled a reassessment of specimens currently referable to G. punctata. We assessed populations genetically using newly generated mitochondrial DNA data in conjunction with recently published phylogenomic data and an unpublished allozyme analysis. In addition, we carried out a detailed morphological examination involving hundreds of specimens across this taxon’s range. Many possible candidate species were recovered from these analyses, and the re-examination of morphology indicated two major clades: one small-bodied and one large-bodied, each comprising multiple divergent lineages within them. A syntype of Peropus variegatus punctatus Fry, 1914, believed to have been lost at the time of Mitchell’s revision in 1965, was recently found in the Western Australian Museum collections, and is here designated as the lectotype of G. punctata sensu stricto.

In addition to G. punctata from the Pilbara craton, the large-bodied clade comprises several species: G. macra sp. nov. – sister to G. punctata and confined to the northern Pilbara, and two more southerly distributed species, G. punctulata sp. nov. and G. polka sp. nov.; and a small-bodied species restricted to the south-western Pilbara region in the Hamersley Range, G. fenestrula sp. nov. Within the small-bodied clade a slightly larger-sized species is described as G. media sp. nov. For the other highly structured small-bodied lineage, one of the groups diverged morphologically and was recovered as the basal group in the phylogenomic data, despite being nested within the small-bodied lineage in the mitochondrial dataset. As this population is also geographically restricted to the Burrup Peninsula, we describe it as G. peninsularis sp. nov., based on the combined evidence. The remaining very small-bodied lineages we describe as G. micra sp. nov.

The new species are diagnosable on the basis of morphology, colour and patterns of pale and dark spots. The revision of the G. punctata species complex adds seven new species to the western arid zone, and further establishes the Pilbara as the region with the highest gecko diversity and endemism in Australia.