Systematics and evolution of Australia’s oldest lizard radiation: the Diplodactyline geckos

A project undertaken at the Western Australian Museum, South Australian Museum and the University of Adelaide, coordinated by Dr Paul Doughty

Australia has a famously diverse lizard fauna that has attracted the attention of evolutionary biologists for many decades. The Diplodactyline geckos are the third most speciose group of Australian lizards. They are endemic to Australasia and widespread across almost all environments. Current data suggest they have been in the Australian environment for far longer than most other lizard groups, which have migrated onto the continent from the north. However in spite of massive advances in techniques for inferring evolutionary history and species boundaries, this group has not yet been the subject of a comprehensive systematic and taxonomic assessment. Thus we are currently unsure of how particular groups relate to each other within the diplodactylines. In many cases there are also populations of geckos that are currently recognised as a single species that may mask the existence of several species. We aim to redress this situation by using multiple genetic loci to examine patterns of evolution and speciation within this group. The project will involve collaboration between the University of Adelaide and the Museums of West Australia and South Australia.

The primary body of work will be undertaken by a PhD student, Paul Oliver, based at Adelaide University. This will involve sequencing numerous mitochondrial genes and nuclear loci from hundreds of geckos. In collaboration with two grantees (Mike Lee and Andrew Hugall) these data will be used to provide a unique insight into how major events in the history of the Australia continent (e.g., aridification) have affected speciation and ecological diversification. These genetic data will also inform subsequent taxonomic research, based on morphological and further genetic data, to be performed by other grantees from the South Australian Museum (Mark Adams) and the Western Australian Museum (Paul Doughty).
Figure 1. Strophurus assimilis – a slender branch mimic with noxious secretions in the tail (photo – M. Hutchinson).

Figure 2. Pygopus lepidopus – an elongate legless terrestrial species (photo – M. Hutchinson).

Figure 3. Nephrurus vertebralis – a large-headed species that includes other geckos in its diet (photo – B. Maryan)