Liming alters body size distribution in a community of epigeic spiders in birch forest (Betula pendula Roth)

International audienceAbstractKey messageLiming, an ameliorative method for acidified forest soils, affected the relative abundance of prey of ground-hunting spiders and consequently reduced densities of functionally similar species of these predators.ContextLiming, an ameliorative method for acidified forest soils, may modify the structure of an arthropod community by altering the soil characteristics and/or the availability of food resources.AimsWe investigated the effect of liming on the community structure of ground-hunting spiders in a birch forest.MethodsWe established six experimental birch stand plots. Each stand was exposed to one of three experimental treatments: control, 1.5 t/ha, or 3 t/ha of dolomitic limestone. We collected spiders using pitfall traps during 5 years. We characterized the community in terms of activity density, species richness, community-weighted mean body size, and functional diversity and evenness in body size. We further investigated the potential links through which the liming might affect spiders, namely soil characteristics, effect of liming on birch, and densities of potential prey.ResultsThe commonly used dosage of 3 t/ha reduced densities of functionally similar species which led to the reduced functional evenness in body size and increased functional divergence in body size. Liming increased soil pH only slightly but decreased the densities of spiders’ preferred prey.ConclusionThe liming affected the community of ground-hunting spiders, at least partially, through reduced densities of their preferred prey

Management Intensity and Forest Successional Stages as Significant Determinants of Small Mammal Communities in a Lowland Floodplain Forest

The conversion of forests from complex natural ecosystems to simplified commercial woodlands is one of the major causes of biodiversity loss. To maintain biodiversity, we need to understand how current management practices influence forest ecosystems. We studied the effects of forest successional stage and management intensity on the abundance, species richness, and assemblage composition of small mammals. Our results show that management intensity significantly contributes to reducing the number of species after clearcutting. We revealed that intensively managed clearings can make the dispersal or foraging activity of small mammals diffcult and hence negatively influence their abundance and species richness. The significantly higher species richness of small mammal species was recorded within more extensively rather than intensively managed clearings. In contrast, we did not observe significant changes in species richness and abundance after intensive management in old-growth forests. Species Clethrionomys glareolus and Apodemus flavicollis reached the greatest abundance in old-growth forest patches. On the other hand, Microtus arvalis and Microtus subterraneus were species mainly associated with the successionally youngest forest stands. Our analysis suggests that intensive management interventions (i.e., vegetation destruction by pesticides and wood debris removal by soil milling) in clearings produce unhostile environments for majority of the small mammal species.O

First data on spiders (Arachnida: Araneae) from dry dipterocarp forests of Thailand

Faunistic records of spiders in dry dipterocarp forests of Thailand are presented. Spiders were surveyed from November 2008 to December 2012. A total of 1,926 spider individuals were collected from 16 locations by visually searching, sweeping grasses and herb vegetation, beating shrubs and trees, and shifting leaf litters. Spiders were identified to 106 species in 86 genera of 29 families. The families Araneidae, Salticidae, Thomisidae, Tetragnathidae, and Theridiidae exhibited higher species richness. Several families that are rare and poorly known in Thailand were recorded, such as Stenochilidae, Eresidae, Idiopidae, Theraphosidae, and Nemesiidae. A faunistic overview of the spiders found in dry dipterocarp forest is presented. In general, the diverse composition of spiders and their guilds and the occurrence of rare and poorly known species in the Thai region confirm the high biotic value of dry dipterocarp forests. Continuing to maintain dry dipterocarp forest functions should be considered in future studies

\u3cem\u3eAlloscorpiops wongpromi\u3c/em\u3e sp. n. from Thailand and Laos (Scorpiones: Euscorpiidae: Scorpiopinae)

Alloscorpiops wongpromi sp. n. from Thailand and Laos is described and compared with all other species of the genus Alloscorpiops Vachon, 1980. A key is presented to all species of the genus. A. wongpromi sp. n. is characterized mainly by a higher number of trichobothria on the patella, which has 33–37 external and 21–22 ventral trichobothria, and a dark-colored telson. The subgenus Laoscorpiops Lourenço, 2013 is synonymized with the nominotypical subgenus, because it was based on misinterpretation of the trichobothrial pattern, with two ventral accessory trichobothria on the chela regarded as part of the external Eb series

A new remarkable species of Alloscorpiops Vachon, 1980 from Myanmar (Burma) (Scorpiones, Scorpiopidae)

Among the genera of the family Scorpiopidae Kraepelin, 1905 Alloscorpiops remains yet rather discrete. New species were added to this genus only recently, increasing its number from two to six. Therefore, species of Alloscorpiops can be considered rare and uncommonly collected. One particular new species, Alloscorpiops viktoriae sp. n., is described based on two females and one pre-adult male collected from the northern part of central Myanmar (Burma). The new species presents most features exhibited by scorpions of the genus Alloscorpiops, but it is characterised by a moderate to small size, very strongly marked granulation, and a particular trichobothrial pattern. Aspects of the ecology and distribution of the new species are discussed and compared with those of other species of genus Alloscorpiops

Araneofauna of the Křéby National Nature Monument (Eastern Moravia, Czech Republic) with some notes to conservation management of the locality

This paper makes a faunistic contribution to knowledge of spider composition in the xerothermic habitats of the Křéby National Nature Monument which is located in Kroměříž district, eastern Moravia. Spiders were collected by four different methods during 25 April–28 October 2013: pitfall traps, sweeping of herb vegetation, individual collecting and beating the branches of shrubs and trees. In total, 1070 individuals (865 adult spiders) were collected and identified as 114 species of 19 families. The species diversity in the Křéby area is rather high, representing approximately 13% of Czech araneofauna. Of the identified species, five are listed in the Red List of Threatened Species in the Czech Republic. These included critically endangered Dysdera hungarica Kulczynski 1897, endangered Alopecosa solitaria (Herman, 1879), Cheiracanthium montanum (C. L. Koch, 1877) and vulnerable Lathys stigmatisata (Menge, 1869) and Haplodrassus dalmatensis (L. Koch, 1866). The findings of Alopecosa solitaria and Dysdera hungarica belong to the northernmost occurrence of these rare species in the Czech Republic. In general, the great richness of spider fauna and the occurrence of rare and threatened species for Czech region confirm the high biotic value of the investigated area. In addition, the author discussed management methods of the locality and suggest management conservation system for slowing down the succession rate on overgrown places

Spiders (Arachnida: Araneae) from Forest Ecosystems of Třesín National Nature Monument (Litovelské Pomoraví, Czech Republic) with Suggestions to Conservation Management of the Locality

This paper presents faunistic records of spiders in the forest ecosystems of the Třesín National Nature Monument. Spiders were surveyed from 29 April 2013 to 25 October 2013. A total of 1012 individual spiders were collected from eight sites by pitfall traps, individual collection, sweeping grasses and herb vegetation, beating shrubs and trees, and shifting leaf litters. Spiders were identified as 146 species from 94 genera and 27 families. The families Linyphiidae, Lycosidae, Gnaphosidae, and Thomisidae exhibited high species diversity. Three species listed on the Red List of Threatened Species in the Czech Republic were recorded: Dysdera moravica (Řezáč, Gasparo, Král & Heneberg, 2014), Megalepthyphantes pseudocollinus (Saaristo, 1997), and Nusoncus nasutus (Schenkel, 1925). The finding of N. nasutus is among the first reports of this spider in the Moravia region. Several findings represent the northernmost occurrences of rare thermophilous spiders in Moravia and even the Czech Republic. The great richness of araneofauna and the occurrence of rare and poorly known spider species confirm the high biotic value of Třesín within the agriculturally intensified landscape of Moravia

Viniční terasy jako refugia pro výskyt xerotermních druhů pavouků (Araneae) a jejich bioindikační využití v hodnocení kvality životního prostředí a úrovně biodiverzity

The large-scale decline of traditionally managed early-successional habitats caused by the joint effects of agricultural intensification and abandonment of marginal lands has resulted in a critical reduction of xerophilous arthopods throughout Europe. The question is whether newly generated early-successional sites of human-made habitats (in this case vineyard terraces) may partially compensate this habitat loss. My research, therefore, focusses on spiders as model organisms to determine the potential importance of xeric slopes of vineyard terraces for biodiversity conservation in agricultural landscapes. I analyzed species density, abundances, rareness degree and conservation value among vineyard terraces with two habitat types of different succession stages (sparse and dense grass turf) placed in in landscapes with varying proportions of surrounding potential source areas (steppe -- foresteppes) and different surrounding habitats (habitat structure) around studied terraces. During 2011 were collected by different methods 6040 adult specimens of spiders belonging to 171 species, 69 genus and 24 families. From this representation were calculated high proportion of rare xeric specialist (40 %) and red-listed threatened species (15 %). From the statistical analyses, overall species density and abundance of spiders did not differ significantly between the terraces with sparse and dense vegetation cover, however species density was significantly influenced by presence of xeric grasslands around vineyards. The occurence of rare and endangered epigeic was significantly associated with the type of successional stage (for epigeic and epiphytic species), as well as rareness degree, conservation value and abundances significantly increased with presence of adjacent steppe grasslands. The results indicate that artificial habitats, such as vineyard terraces, are important refuges for wide spectra of xerothermophilous spiders. To prevent losses of rare and endangered xeric species, I suggest some small scale management methods that maintain important microhabitat mosaic structures under the different succession stages