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Both habitat structural complexity and prey availability can influence the density and diversity of spider assemblages. We studied whether prey availability affects spider assemblages living on the bark of European black pine (Pinus nigra Arnold) in six localities in Hungary. We found both positive and negative relationships between spider and prey assemblages in a sample of 1290 spiders and 24 186 potential prey when among-locality variation in spider assemblages was controlled for. Species richness, number of individuals, and diversity of spiders increased with either the number of prey taxa or the number of prey individuals in a forest in western Hungary. Spider species richness and number of individuals increased with prey diversity but decreased with number of prey taxa in moderately air-polluted urban localities. There was a negative relationship between number of spider individuals and number of prey individuals in a heavily polluted urban locality. Numbers of nocturnal hunters but not diurnal hunters or web-builders increased with the number of their respective prey in the forest in western Hungary and in the moderately air-polluted urban localities. The number of exclusive bark-dwelling spiders increased with the number of prey individuals in forests in eastern Hungary and decreased with the number of prey individuals in the polluted urban locality. We suggest that patterns of spider assemblages can be influenced by prey availability and that other factors (e.g., habitat structural diversity and air pollution) also need to be considered in explaining these patterns.

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A B S T R A C TPrevious studies reported that landscape-level factors are vital to support diversity of spiders in strongly modified arable lands and disturbed habitats such as managed semi-natural grasslands. Cropland management (ploughing, fertilization, and pest management) Q3 and agricultural practices (mowing and grazing) destroy and/or modify regularly the spider assemblages; thus, continuous recolonization from the surrounding landscape is vital to sustain the species pool. On the contrary, we hypothesized that in unmanaged grasslands, the spider assemblages are stable and the importance of recolonization is limited, the local factors become much more important drivers in shaping spider assemblages than landscape-level factors. We tested the importance of local and landscape-level factors on the abundance and species richness of spiders in unmanaged grasslands. At the landscape-level, we found that only the isolation had significant effect on the total abundance, on the abundance of hunting and habitat specialist species, and on the abundance of a frequent species (Gnaphosa mongolica). At the local scale, however, four out of five studied factors influenced significantly the species richness and abundance of spider assemblages and the abundance of two frequent species (Alopecosa psammophila, Berlandia cinerea). Species richness and abundance increased by plant cover, litter cover, and patch size, while decreased by bare ground cover. We found that in unmanaged grasslands, the local factors had vital role in maintaining the spider species richness; this is just the opposite conclusion that was earlier reported for agricultural ecosystems, where landscape-level effects had crucial role providing the species for continuous recolonization.2015 Published by Elsevier B.V. the local scale and the landscape-level scale) in these habitats 33 (Tscharntke et al., , 2012Batáry et al., 2008

This paper presents electron micrographs of the genitalia of Alopecosa psammophila, describes the morphological characteristics of the species and also gives information on its habitat preference, the co-occurring ground-dwelling spiders, and the phenological characteristics of the species. Barber pitfall trappings have been carried out since 2000 in dry sandy grasslands in three regions of Hungary: the Kiskunsag area (Kiskunsag National Park); the Nyirseg area (Hortobagy National Park); and since 2004 the Kisalfold area (Ferto-Hansag National Park). Specimens of the species, hitherto unknown in Hungary, have been collected from 17 localities in all three areas. We collected specimens in calciferous open sand steppes and in acidic open sand steppes. In the females, two activity periods were apparent (from April to end July and in October). A few males were collected in April and in October-November they had an extreme activity peak. We assume that the species has adult specimens throughout the winter. Alopecosa psammophila is most similar to Xysticus ninni Thorell, 1872 and Zelotes longipes (L. Koch 1866) in terms of its environmental needs.

NIEL L. BRUCE1'3), CSABA SZINETÁR4) and NICO J. SMIT1'5) ') Water ABSTRACT Cemtothoa retusa (Schioedte & Meinen, 1883) is redescribed from the lectotype (here desig nated) collected from Mozambique, and the range is extended to include the Gulf of Suez in the Red Sea. Ceratothoa retusa is distinctive within the genus with a manifestly small head deeply immersed into pereonite 1, which has prominent, but variable, projecting anterolateral margins. Ceratothoa re fusa has a tropical and subtropical Indian Ocean distribution, extending from eastern Africa (and now the Red Sea) eastwards to northern Australia and Indonesia. The only known hosts are the halfbeaks, Hemiramphus far (Forsskäl, 1775) and H. robustus Günther, 1866 (Hemiraphidae). RÉSUMÉ Ceratothoa retusa (Schioedte & Meineit, 1883) est redécrite à partir du lectotype (désigné ici) collecté au Mozambique, et sa répartition est étendue pour inclure le Golfe de Suez dans la Mer Rouge. Ceratothoa retusa se distingue à l'intérieur du genre par une tête manifestement petite, profondément enfoncée dans le péréonite 1, qui possède des bords antérolatéraux proéminents et saillants, mais variables. Ceratothoa retusa a une répartition tropicale et subtropicale dans l'Océan Indien, allant de l'Afrique orientale (et maintenant la Mer Rouge) vers l'Est jusqu'au Nord de l'Australie et l'Indonésie. Les seuls hôtes connus sont les Hemiramphidae, Hemiramphus far (Forsskâl, 1775)