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Sclerophyll woodlands and open forests once covered vast areas of eastern Australia, but have been greatly fragmented and reduced in extent since European settlement. The biogeographic and evolutionary history of the biota of eastern Australia’s woodlands also remains poorly known, especially when compared to rainforests to the east, or the arid biome to the west. Here we present an analysis of patterns of mitochondrial genetic diversity in two species of Pygopodid geckos with distributions centred on the Brigalow Belt Bioregion of eastern Queensland. One moderately large and semi-arboreal species, Paradelma orientalis, shows low genetic diversity and no clear geographic structuring across its wide range. In contrast a small and semi-fossorial species, Delma torquata, consists of two moderately divergent clades, one from the ranges and upland of coastal areas of south-east Queensland, and other centred in upland areas further inland. These data point to varying histories of geneflow and refugial persistance in eastern Australia’s vast but now fragmented open woodlands. The Carnarvon Ranges of central Queensland are also highlighted as a zone of persistence for cool and/or wet-adapted taxa, however the evolutionary history and divergence of most outlying populations in these mountains remains unstudied.

[Extract] Paradelma orienralis is a member of the monophyletic and endemic family of Australian lizards, the Pygopodidae (Kluge 1974). Until relatively recently P. orientalis was known only from a small number of scattered localities exclusively within the central and southem Brigalow Belt region, east of the Great Dividing Range in south-central Queensland (Wilson and Knowles 1988; Cogger et al. 1993). New populations are now known for the southern, eastern and western extremes of this bioregion (Schulz and Eyre 1997; Tremul 1999). The eponymous common name implies P. orientalis has a strong association with the Brigalow Belt and this is certainly its core distribution (Covacevich et al. 1998). Habitat is generically reported as woodland consisting of, or associated with, Brigalow Acacia harpophylla vegetation (Wilson and Knowles 1988; Cogger er al. 1993; Sattler and Williams 1999), though a range of other Eucalyptus woodland associations without Brigalow have been recorded (Shea 1987; Wilson and Knowles 1988; Schulz and Eyre 1997; Tremul 1999). Many of these have a dense sub-canopy of other rough-barked species such as Callitris columellaris, Allocasuarina luehmanni and Acacia falciformis (Schulz and Eyre 1997; Tremul 1999). The biology of the species is poorly known. It is known to be oviparous, laying two eggs (Greer 1989), and detailed observations of a population on Boyne Island indicate it clearly noctural, active in temperatures generally above 19°C, partly arboreal, and both a sap and invertebrate feeding species (Tremul 1999). Sap feeding is unreported for other Pygopodids (Tremul 1999), but has been observed for geckos (Couper et al. 1995). The Brigalow Belt is one of the most highly modified and poorly reserved bioregions in Queensland (Covacevich et al. 1998; Sattler and Williams 1999) and almost no baseline or detailed bioregional fauna survey was conducted in the Brigalow Belt prior to the onset of extensive land clearance schemes in the 1960's (Gordon 1984; Covacevich et al. 1998). Twenty-seven reptiles are considered restricted to, or significantly distributed within, this bioregion, eighteen being of conservation significance (Covacevich et al. 1998). Paradelma orientalis is listed as vulnerable in Queensland under the Nature Conservation Legislation Amendment Regulation (No. 2) 1997 and Action Plan for Australian Reptiles (Cogger et al. 1993), though its continued appearance in new locations caused some authors to consider its conservation status requiring further investigation (Schulz and Eyre 1997). Habitat modification and conversion of native woodland to pasture and agriculture is considered to have had a severe impact on the pre-European distribution and abundance of this species (Gordon 1984; Cogger et al. 1993; Covacevich et al. 1998). This note reports new locality data for P. orientalis collected incidentally during large-scale vertebrate fauna surveys in the Desert Uplands and Northern Brigalow Belt. Habitat data and implications for conservation status are discussed.