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Daily activity patterns of the endemic Soutpansberg rock lizard (Australolacerta rupicola) and ecologically similar syntopic lizards were analysed to assess potential niche partitioning. Data to evaluate the temporal niche included time and temperature, and niche overlap was determined over three different sample plots using the Pianka-Index. Altogether, 11 other lizard species and four snake species were recorded at the sample plots. Australolacerta rupicola showed a large overlap i n the spatial niche with Trachylepis varia and Platysaurus relictus and in the trophic niche with T. varia, however, the maximum activity period of A. rupicola fell into periods of low activity by P. relictus and T. varia and vice versa. These patterns were most pronounced when the different sample plots were analysed separately. The asynchronous activity cycles are probably the result of avoidance of competition for food in the case of the active foragers A. rupicola and T. varia, whereas different thermal preferences driven by physiological constraints appear to be more relevant when comparing A. rupicola and P. relictus. Individual numbers of the usually abundant species T. varia and P. relictus decreased in A. rupicola habitats and it is posted that the latter species resides in less climatically favourable habitats, thus avoiding competition with other rupicolous lizards. [ABSTRACT FROM AUTHOR]

Abstract: Fauna lists from nature reserves, game reserves and national parks are commonly used to depict modern fauna communities in synecological studies for the reconstruction of palaeocommunities and palaeoenvironments. This relies on the assumption that the modern fauna lists are truly representative samples of the communities they constitute. This study seeks to identify limitations in the use of such lists and to explore ways to mitigate or address some of the associated problems. We use modern fauna communities from national parks and game reserves in Asia. Potential limitations identified in the use of the modern fauna lists include under-representation of particular taxonomic groups; taxonomically unrepresentative lists; and unrepresentative habitat descriptions for the communities. In this study, the potential for under-representation of particular taxonomic groups is addressed by restricting the analysis to large-bodied fauna; fauna lists are subjected to taxonomic distinctness analysis to distinguish lists which are taxonomically representative from those which are not; and habitat descriptions are not accepted a priori but instead fauna lists are subjected to cluster and principle components analysis in order to identify the most parsimonious habitat groupings on the basis of the fauna. The minimum number of species required in the characterization of modern communities to confidently differentiate between the habitat types they utilize is also quantified. A synecological analysis for the Gongwangling palaeocommunity, Lantian, China is presented on the basis of data from protected natural areas whose limitations have been addressed. This analysis suggests a reconstruction of closed habitat for Gongwangling. [Copyright &y& Elsevier]