Microhabitat Selection for Overwintering: Overwintering Conditions of Three Jumping Spiders (Pellenes tripunctatus, P. nigrociliatus, and Attulus penicillatus) Living in Terrestrial Shells in the Czech Republic.

Taking the regular overwintering of spider species in land snail shells as a model, we studied environmental conditions affecting the choice of overwintering sites in three jumping spider species: Pellenes tripunctatus, Pellenes nigrociliatus, and Attulus penicillatus. The research was conducted at 11 steppe localities on calcareous bedrock with abundant empty shells (mainly Caucasotachea vindobonensis and Xerolenta obvia). We documented 889 shells and collected 186 of them, of which 113 were inhabited by 146 spider individuals (13 species). Our three focal species made up 81.5% of these. We found different environmental preferences between the sexes in P. tripunctatus and P. nigrociliatus. These females preferred shells with more vegetation nearby. In the case of P. tripunctatus, these were shells with a higher proportion of herbs, whereas P. nigrociliatus selected for a higher proportion of moss. In the immediate vicinity of the shells, environmental conditions did not differ significantly. We found insufficient A. penicillatus to determine any preferences. We also recorded six overwintering P. tripunctatus individuals in a single shell (in environmental conditions preferred by females), consisting of five females and one male, which indicated an unusual social behavior for these spider species.

Improving the Knowledge on Distribution, Food Preferences and DNA Barcoding of Natura 2000 Protected Species Paracossulus thrips (Lepidoptera, Cossidae) in Romania.

Paracossulus thrips (Lepidoptera, Cossidae) is one of the locally distributed and endangered species. In Europe, it is also one of the few protected moth species, through Annexes II and IV of the Council Directive 92/43/EEC, Annex II of the Bern Convention. To date, little is known about the biology and ecology of this species. Our study was conducted in Transylvania, Romania. Romania hosts some of the strongest populations of the species in the European region. As part of the study, we conducted field observations, vegetation analyses, and genetic analyses. In our paper, we show the habitat types where we encounter P. thrips in Transylvania and confirm Phlomis tuberosa as a host plant. Furthermore, a piece of important information for habitat conservation is given. In this paper, we present the eggs and larvae of P. thrips, the first DNA barcoding sequences, and four new populations of P. thrips in Romania. Our study provides baseline knowledge about the biology and ecology of P. thrips, which is important for conservation and establishing management measures.

Patterns of host use by brood parasitic Maculinea butterflies across Europe.

The range of hosts exploited by a parasite is determined by several factors, including host availability, infectivity and exploitability. Each of these can be the target of natural selection on both host and parasite, which will determine the local outcome of interactions, and potentially lead to coevolution. However, geographical variation in host use and specificity has rarely been investigated. Maculinea (= Phengaris) butterflies are brood parasites of Myrmica ants that are patchily distributed across the Palæarctic and have been studied extensively in Europe. Here, we review the published records of ant host use by the European Maculinea species, as well as providing new host ant records for more than 100 sites across Europe. This comprehensive survey demonstrates that while all but one of the Myrmica species found on Maculinea sites have been recorded as hosts, the most common is often disproportionately highly exploited. Host sharing and host switching are both relatively common, but there is evidence of specialization at many sites, which varies among Maculinea species. We show that most Maculinea display the features expected for coevolution to occur in a geographic mosaic, which has probably allowed these rare butterflies to persist in Europe. This article is part of the theme issue 'The coevolutionary biology of brood parasitism: from mechanism to pattern'.

Patterns of functional diversity of two trophic groups after canopy thinning in an abandoned coppice.

Coppice abandonment had negative consequences for biodiversity of forest vegetation and several groups of invertebrates. Most coppicing restoration studies have focused only on a single trophic level despite the fact that ecosystems are characterized by interactions between trophic levels represented by various groups of organisms. To address the patterns of functional diversity in the perspective of coppicing restoration, we studied the short-term effects of conservation-motivated tree canopy thinning in an abandoned coppice-with-standards in Central Europe, a region where such attempts have been rare so far. The functional diversity of vascular plants and spiders, chosen as two model trophic groups within a forest ecosystem, was compared between thinned and control forest patches. To characterize functional patterns, we examined several functional traits. These traits were assigned into two contrasting categories: response traits reflecting a change of environment (for both vascular plants and spiders) and effect traits influencing the ecosystem properties (only for vascular plants). Functional diversity was analysed by CCA using two measures: community-weighted means (CWM) and Rao's quadratic diversity (RaoQ). CCA models revealed that the canopy thinning had a positive effect on diversity of the response traits of both trophic groups and negatively influenced the diversity of effect traits. In addition, we found distinct seasonal dynamics in functional diversity of the spider communities, which was probably linked to leaf phenology of deciduous trees and therefore an effect trait not directly examined in this study. We conclude that canopy thinning affected functional diversity across trophic groups during the initial phase of coppicing restoration. With necessary precautions, careful canopy thinning can be effectively applied in the restoration of functional diversity in abandoned coppices.

Sublethal effect of agronomical surfactants on the spider Pardosa agrestis.

In addition to their active ingredients, pesticides contain also additives - surfactants. Use of surfactants has been increasing over the past decade, but their effects on non-target organisms, especially natural enemies of pests, have been studied only very rarely. The effect of three common agrochemical surfactants on the foraging behavior of the wolf spider Pardosa agrestis was studied in the laboratory. Differences in short-term, long-term, and overall cumulative predatory activities were investigated. We found that surfactant treatment significantly affected short-term predatory activity but had no effect on long-term predatory activity. The surfactants also significantly influenced the cumulative number of killed prey. We also found the sex-specific increase in cumulative kills after surfactants treatment. This is the first study showing that pesticide additives have a sublethal effect that can weaken the predatory activity of a potential biological control agent. More studies on the effects of surfactants are needed to understand how they affect beneficial organisms in agroecosystems.

Impact of Canopy Openness on Spider Communities: Implications for Conservation Management of Formerly Coppiced Oak Forests.

Traditional woodland management created a mosaic of differently aged patches providing favorable conditions for a variety of arthropods. After abandonment of historical ownership patterns and traditional management and the deliberate transformation to high forest after World War II, large forest areas became darker and more homogeneous. This had significant negative consequences for biodiversity. An important question is whether even small-scale habitat structures maintained by different levels of canopy openness in abandoned coppiced forest may constitute conditions suitable for forest as well as open habitat specialists. We investigated the effect of canopy openness in former traditionally coppiced woodlands on the species richness, functional diversity, activity density, conservation value, and degree of rareness of epigeic spiders. In each of the eight studied locations, 60-m-long transect was established consisting of five pitfall traps placed at regular 15 m intervals along the gradient. Spiders were collected from May to July 2012. We recorded 90 spider species, including high proportions of xeric specialists (40%) and red-listed threatened species (26%). The peaks of conservation indicators, as well as spider community abundance, were shifted toward more open canopies. On the other hand, functional diversity peaked at more closed canopies followed by a rapid decrease with increasing canopy openness. Species richness was highest in the middle of the canopy openness gradient, suggesting an ecotone effect. Ordinations revealed that species of conservation concern tended to be associated with sparse and partly opened canopy. The results show that the various components of biodiversity peaked at different levels of canopy openness. Therefore, the restoration and suitable forest management of such conditions will retain important diversification of habitats in formerly coppiced oak forest stands. We indicate that permanent presence of small-scale improvements could be suitable conservation tools to prevent the general decline of woodland biodiversity in the intensified landscape of Central Europe.