title: Young relicts and old relicts: a novel palaeoendemic vertebrate from the Australian Central Uplands.
abstract: Climatic change, and in particular aridification, has played a dominant role in shaping Southern Hemisphere biotas since the mid-Neogene. In Australia, ancient and geologically stable ranges within the vast arid zone have functioned as refugia for populations of mesic taxa extirpated from surrounding areas, yet the extent to which relicts may be linked to major aridification events before or after the Pliocene has not been examined in detail. Here we use molecular phylogenetic and morphological data to show that isolated populations of saxicoline geckos in the genusOedurafrom the Australian Central Uplands, formerly confounded as a single taxon, actually comprise two divergent species with contrasting histories of isolation. The recently resurrectedOedura cinctahas close relatives occurring elsewhere in the Australian arid biomes with estimated divergence dates concentrated in the early Pliocene. A new taxon (described herein) diverged from all extantOeduramuch earlier, well before the end of the Miocene. A review of data for Central Uplands endemic vertebrates shows that for most (includingOedura cincta), gene flow with other parts of Australia probably occurred until at least the very late Miocene or Pliocene. There are, however, a small number of palaeoendemic taxa-often ecologically specialized forms-that show evidence of having persisted since earlier intensification of aridity in the late Miocene.
authors.affiliation: Division of Evolution, Ecology and Genetics, Research School of Biology and Centre for Biodiversity Analysis , The Australian National University , Building 116, Daley Road, Acton, Australian Capital Territory 2601 , Australia.
authors.forename: Paul M
authors.identifier: 0000-0003-4291-257X
authors.initials: PM
authors.lastname: Oliver
authors.affiliation: Flora and Fauna Division , Department of Land Resource Management , Alice Springs, Northern Territory 0870 , Australia.
authors.forename: Peter J
authors.identifier: 0000-0001-6875-1466
authors.initials: PJ
authors.lastname: McDonald
keywords: Pliocene; aridification; climate change; evolutionary refugia; gecko; relict