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Agricultural intensification is a major threat to biological diversity worldwide. Land management activities enhancing landscape diversity are therefore regarded as a key strategy to halt species loss in cultural landscapes. Diverse and abundant communities of predatory arthropods, e.g. spiders (Araneae), have a high potential to suppress pest populations (Symondson et al. 2002) and could therefore contribute to allow reductions of pesticide use. Crop fields alone are usually not able to sustain diverse and individual-rich populations of predatory arthropods, because agricultural management results in disturbances and habitat deteriorations (harvest, soil cultivation, pesticide application) that kill or drive away large parts of the populations. Therefore semi-natural and perennial habitats in agricultural landscapes are considered to be of great importance for beneficial arthropods. On the one hand they offer refuge habitats in times when arable fields are hostile, e.g. fields with bare grounds during winter (Schmidt & Tscharntke 2005). On the other hand, viable populations of predatory arthropods in semi-natural habitats can serve as sources for (re-) colonisation of arable fields (Schmidt & Tscharntke 2005). Because of these exchanges between crop and non-crop areas it is important to include the surrounding landscape when investigating field-scale processes. We investigated the relations between spider assemblages in arable fields and the surrounding landscape in 29 fields of winter oilseed rape (OSR) in an agricultural landscape in eastern Austria. The objectives of this study were to estimate (1) how much spider assemblages in oilseed rape fields are influenced by the surrounding landscape, (2) the relative influence of landscape variables compared to field-scale variables and (3) at which spatial scales landscape variables are effective.
Spider fauna of semi-dry grasslands on a military training base in Northwest Germany (Münster)
(2008)
The spider fauna of semi-dry grasslands on the military training area of Dorbaum near Münster (North Rhine-Westphalia) was investigated. From 2002 to 2003 a total of 11,194 mature spiders from 141 species and 20 families was caught by pitfall trapping and hand sampling. Among them are 18 species listed in the Red Data Book of North Rhine-Westphalia, four species are rare or previously rarely recorded. Most of the spiders are habitat generalists that extend their occurrence into all types of habitats, while the number of species which are stenotopic to sand habitats is noticeably low (n = 13). The spider data were analysed with Principal Component Analysis (PCA). It is possible to distinguish spider communities of neighbouring forested habitats from species groups of open habitats, but there is no uniform spider community which is characteristic for semi-dry grassland.
A new species of the basal araneomorph spider genus Ectatosticta (Araneae, Hypochilidae) from China
(2009)
The hypochilid spider Ectatosticta davidi (Simon) is redescribed on the basis of adults from Mt. Taibaishan in Shaanxi Province, China; the specimens from Qinghai Province previously identified as E. davidi by most modern authors belong to a new species described as E. deltshevi. Keywords: Araneae, Araneomorphae, Hypochilidae, Ectatosticta, China
Based on a collection of spiders obtained during ecological fieldwork in 2009 and an extensive literature review, we summarize the current state of knowledge of spider biodiversity on the island of Maio. The total number of species reported from Maio is now 46, representing 18 families and including 16 species (35%) endemic to the Cape Verde Islands. The family Dictynidae (meshweb spiders), represented by the saline-adapted Devade cf. indistincta, is reported for the first time from Cape Verde.
Spatial and temporal structure of the spider community in the clay semi-desert of western Kazakhstan
(2011)
The spatial and temporal structure of spider communities was studied in the clay semi-desert of the north-western Caspian Lowland, western Kazakhstan (49°23' N, 46°47' E). The soils and vegetation are complex, being composed of a mosaic of desert and steppe plant communities. Besides the native associations, there are plantations of different tree species. The ground-dwelling spider assemblages in the native habitats are the most diverse. The number of species inhabiting forest plantations is three times as small. Gnaphosidae is the leading family in the ground layer. They show high abundance and diversity levels during the whole season. Thomisidae, Lycosidae, Philodromidae, and Salticidae are abundant as well. The species diversity of herbage-dwelling spiders in different open native habitats is very similar. The spectrum of dominant families (Thomisidae, Oxyopidae, Araneidae, and Salticidae) and the seasonal dynamics of their ratio in desert and steppe associations have much in common. Spider assemblages of native and artificial habitats are characterised by change from multispecies polydominant spring-summer communities to impoverished imbalanced autumn ones. Seasonal changes in the species structure of mature spider groupings in native habitats are well pronounced, while the impact of seasonal conditions is even stronger than between-habitat differences. Complexes of typical species with different levels of habitat preference are revealed.
Spiders leave draglines, faeces and other secretions behind when traveling through their microhabitat. The presence of these secretions may unintentionally inform other animals, prey as well as predators, about a recent and possible current predation risk or food availability. For a wolf spider, other spiders including smaller conspecifics, form a substantial part of their prey, and larger wolf spiders, again including conspecifics, are potential predators. We tested two hypotheses: that large wolf spiders may locate patches of potential spider prey through the presence of silk threads and/or other secretions; and that prey spiders may use secretions from large wolf spiders to avoid patches with high predation risk. We used large (subadult or adult) Pardosa saltans to provide predator cues and mixed dwarf spiders or small (juvenile) P. saltans to provide prey cues. Subadult wolf spiders were significantly attracted to litter contaminated by dwarf spiders or small conspecifics after 6 hours but no longer after 24 hours. In contrast, neither dwarf spiders nor small P. saltans showed significant avoidance of substrate contaminated by adult P. saltans. However, small P. saltans showed different activity patterns on the two substrates. The results indicate that wolf spiders are able to increase the efficiency of foraging by searching preferentially in patches with the presence of intraguild prey. The lack of a clear patch selection response of the prey in spite of a modified activity pattern may possibly be associated with the vertical stratification of the beech litter habitat: the reduced volume of spaces in the deeper layers could make downward rather than horizontal movement a fast and safe tactic against a large predator that cannot enter these spaces.
The present study summarises spider records from East Macedonia and Thrace (NE Greece). Spiders were mainly collected by hand sampling and to a smaller extent by pitfall trapping during field trips in 2002, 2004, 2007, 2008 and 2009. 171 species from 23 families were sampled. Pelecopsis pavida (O. P.-Cambridge, 1872) (Linyphiidae) and Xysticus kaznakovi Utochkin, 1968 (Thomisidae) were new to the European spider fauna and ten further species, Diaea livens Simon, 1876, Heriaeus graminicola (Doleschall, 1852), Meioneta ressli Wunderlich, 1973, Oedothorax retusus (Westring, 1851), Philodromus albidus Kulczynski, 1911, Pocadicnemis pumila Keyserling, 1880, Sitticus saltator (O. P.-Cambridge, 1868), Stemonyphantes lineatus (Linnaeus, 1758), Synageles scutiger Prószynski, 1979 and Thanatus coloradensis Keyserling, 1880, could be added to the Greek fauna for the first time. 21 and 38 species were new to East Macedonia and Thrace, respectively. Based on previous work, plus the present study, the Greek spider fauna now includes 1,108 species.
Spiders were collected by pitfall traps in the south-western archipelago of Finland. Wooded study habitats on a small-sized (1.2 km2) island were: 1) natural open ash grove, 2) dense mixed grove (old overgrown wooded meadow), 3) wooded aspen pasture and 4) wooded meadow, both restored ten years earlier, 5) natural wooded meadow. Highest species and family numbers were found at the natural sites (1 and 5) and the lowest in the dense grove (site 2). Linyphiidae dominated, both at species and individual level, in the groves. Lycosidae were abundant on the wooded meadows and Gnaphosidae on the wooded pasture. The highest faunal similarities were between the groves (70 % species in common) and between the wooded meadows (64 %). The lowest similarity was found between the dense grove (17 %) and the ash grove (23 %) with the aspen pasture. Ten years after clearing, sites 3 and 4 had diverse spider faunas. The fauna at site 4 resembled that on the corresponding natural site (5), thus showing restoration success. Altogether 84 species of spiders were caught. The proportion of Gnaphosidae (16 species found) is high. Most species found in the study are common in south-western Finland and many occur across the whole country. Pardosa lugubris was most dominant at three sites, P. pullata and Diplostyla concolor both at one site. Two species, Enoplognatha thoracica and Micaria fulgens, are included in the Finnish Red Data Book.
An annotated catalogue of the rare mesothele spiders (Araneae: Mesothelae: Liphistiidae) held in the Museum für Naturkunde Berlin is presented. The museum hosts non-type specimens of nine species representing all three currently recognised genera, namely: Liphistius desultor Schiödte, 1849, L. malayanus cameroni Haupt, 1983, L. cf. thaleban Schwendinger, 1990, Heptathela kikuyai Ono, 1998, H. kimurai (Kishida, 1920), H. yanbaruensis Haupt, 1983, Ryuthela ishigakiensis Haupt, 1983, R. nishihirai (Haupt, 1979) and R. tanikawai Ono, 1997 (spec. reval.). The geographical focus of this collection is Malaysia and Japan, and most of the material was collected by the Berlin-based zoologist Joachim Haupt.
The rhythm of biodiversity loss vastly surpasses the number of new species described per year, with several taxa going extinct without us even knowing about their existence. After more than 250 years of traditional taxonomy, it is clear that the rate of biodiversity description and discovery needs to be improved. Molecular data has greatly increased the speed of species discovery and accuracy of taxonomic delimitation. Phenotypic documentation, although relatively slower, is still crucial to identify species and communicate taxonomic discoveries to a broader audience. Here, we integrate these data sources to describe a relatively large number of new species of the spider genus Anyphaena and look into its internal phylogenetic relationships. Our findings support the existence of several species groups within Anyphaena (as currently defined), but failed to recover the monophyly of this genus, suggesting a more comprehensive revision of its species groups and closely related anyphaenid genera is necessary. The 21 new species described here are: Anyphaena adnani sp. nov., A. bifurcata sp. nov., A. dulceae sp. nov., A. epicardia sp. nov., A. fernandae sp. nov., A. franciscoi sp. nov., A. ibarrai sp. nov., A. jimenezi sp. nov., A. megamedia sp. nov., A. miniducta sp. nov., A. natachae sp. nov., A. noctua sp. nov., A. porta sp. nov., A. quadrata sp. nov., A. rebecae sp. nov., A. salgueiroi sp. nov., A. sofiae sp. nov., A. stigma sp. nov., A. tonoi sp. nov., A. triangularis sp. nov. and A. urieli sp. nov.