Search

In glacier forelands spiders constitute a large proportion of the invertebrate community. Therefore, it is important to be able to determine the species that can be found in these areas. Linyphiid and theridiid spider identification is currently not possible in juvenile specimens using traditional morphological based methods, however, a large proportion of the population in these areas are usually juveniles. Molecular methods permit identification of species at different life stages, making juvenile identification possible. In this study we tested a molecular tool to identify the 10 most common species of Linyphiidae and Theridiidae found in three glacier foreland communities of the Austrian Alps. Two multiplex PCR systems were developed and over 90% of the 753 field-collected spiders were identified successfully. The species targeted were found to be common in all three valleys during the summer of 2010. A comparison between the molecular and morphological data showed that although there was a slight difference in the results, the overall outcome was the same independently of the identification method used. We believe the quick and reliable identification of the spiders via the multiplex PCR assays developed here will aid the study of these families in Alpine habitats. [ABSTRACT FROM AUTHOR]

Abstract: Faecal pellets of macro-decomposers form an important component of upper soil layers. It is, however, not yet specifically known which species’ faecal pellets are important in the process of humus and soil formation. Here we present a novel approach, based on the detection of short DNA fragments, to species-specifically assign faecal pellets to their detritivorous producers. Using diagnostic polymerase chain reaction (PCR), DNA of the two millipede species Cylindroiulus fulviceps and C. meinerti, abundant macro-decomposers on European alpine pastureland, could be detected in their faecal pellets. Although in both species detection was possible up to 5 days post-defecation (no longer intervals were tested), detection rates were significantly higher in C. fulviceps (81.3%) than in Cylindroiulus meinerti (60.9%) in repetitive PCRs. Employing a binomial mixture model, the probability that the producer’s DNA was present in a faecal sample which tested negative in five subsequent PCRs was estimated as 22.0% for C. fulviceps and 41.9% for C. meinerti, suggesting to adopt a flexible stopping rule for assaying this type of samples. This proof-of-concept study demonstrates that the molecular assignment of faecal pellets to their macro-invertebrate producers is possible, offering a new approach to examine the role of decomposer faecal pellets in soil formation and functioning as well as to complement molecular profiling of faunal communities. [Copyright &y& Elsevier]