Andrew P. Amey

Skinks currently assigned to Carlia aerata (Scincidae: Lygosominae) of north-eastern Queensland: a preliminary study of cryptic diversity and two new species.

A preliminary investigation of genetic diversity in Carlia aerata, by sequencing the mitochondrial ND4 gene, revealed the presence of two cryptic species, described herein. The sequence data was added to an existing phylogeny to discern molecular relationships. Interestingly, genetic affinities lie not with C. aerata, the species to which they key. Instead, one has affinities with C. tanneri, the other with C. foliorum. This casts doubt on the validity of morphological characters alone to infer relationships within this genus. Despite low levels of genetic divergence from sister taxa, the new species can be diagnosed from these by morphological characters that exhibit little or no intraspecific variation. The addition of these new species to the gene tree did not enhance resolution of the phylogenetic relationships at the deeper nodes of the Carlia tree. The discovery of these two new cryptic species provides further support for a previously suggested rapid mid-Miocene diversification of Carlia that may have resulted from the successful expansion of a rainforest-dwelling ancestor into the expanding woodlands associated with Miocene climate fluctuations.

Distribution and population genetic structure of the critically endangered skink Nangura spinosa, and the implications for management

Many threatened species occur as small, isolated populations. Understanding the extent and genetic distinctiveness of these populations is essential for management. Nangura spinosa is a critically endangered skink known from two small populations in dry rainforest in south-east Queensland. We conducted targeted surveys between 2001 and 2010 at the two known N. spinosa sites (Nangur National Park, Oakview National Park area) and in 22 nearby forest blocks with potentially suitable habitat. N. spinosa was found only at the two previously known sites, which are similar to 36 km apart. The skink appears to be declining at Nangur NP, to an estimated extent of occurrence of 7.4 ha and potentially no more than 35 adults. In contrast, we increase the extent of occurrence at Oakview to 360 ha, where the population is at least in the hundreds. Sequencing of two mtDNA genes revealed considerable genetic divergence between the two populations (3.8% for ND4; 1.2% for 16S), suggesting an extended period of separation. Population fragmentation is therefore not the result of recent land clearing, but of long-term isolation by unsuitable habitat. Each population should be considered a distinct management unit. More data are required on population size and trends, recruitment and threats, particularly for the Nangur population.