A reassessment of Saltuarius swaini (Lacertilia: Diplodactylidae) in southeastern Queensland and New South Wales; two new taxa, phylogeny, biogeography and conservation
Abstract
The Saltuarius swaini lineage comprises four species: S. swaini (Wells & Wellington, 1985), S. wyberba (Couper et al., 1997), S. moritzi n.sp. and S. kateae n.sp. These are diagnosed by scalation and colour pattern differences; high levels of discrimination between these species were obtained in genetic and multivariate morphological analyses. Two species, Saltuarius swaini and S. wyberba, occur in both southeastern Queensland and northeastern N.S.W. The former is a rainforest obligate, the latter saxicolous. Saltuarius moritzi and S. kateae n.spp. are restricted to northeastern N.S.W. The former is widespread and the least specific in geological and substrate associations. The latter is restricted to the Mt Marsh area. The genus has a rainforest ancestry. Divergence within the "S. swaini " lineage may date to the latest Eocene–Early Miocene. We hypothesize that populations of ancestral leaf-tailed geckos would have been severely fragmented since the Mid Tertiary forcing retreat to rainforest refugia and driving allopatric speciation. Some populations shifted from trees to rocks. All four taxa are well-represented in existing reserves. Saltuarius swaini, a species with a continuous rainforest history and low levels of genetic variation, may be disadvantaged by ecological stasis in the face of global warming.
