Assemblages of ground-living spiders (Araneae) and harvestmen (Opiliones) of the recultivated old chemical waste dump in Vrakuňa (Bratislava, Slovakia)

This research was conducted to study assemblages of selected ground-living arachnids of the chemical waste dump in Vrakuňa (Bratislava, Slovakia). Arachnids were sampled between October 2018 and October 2019 at three study sites using pitfall traps. In total 3,261 spider individuals, belonging to 92 species and to 24 families, and 1,284 harvestman individuals, belonging to eight species and to four families, were captured. The identified spider species were divided into five groups according to their different habitat type preference and on the basis of association with the originality of habitats and their expansion/invasion potential. The studied assemblages of arachnids were compared according to their composition and analyse the variation of species occurrence across the study sites was done. In order to evaluate the relationship between the assemblages of the spiders and harvestmen at the sampling sites, we used multivariate analysis. The biplot of correspondence analysis formed groups of species with different preferences for humidity and light conditions at individual study sites. The research found the species Zodarion italicum , recorded for the first time in Slovakia. The characteristic features of the spider species found, photos of habitus and genitalia, notes on phenology, habitat, an overview of the presently known distribution, and the dominant species of spider assemblages are here presented.