Spider Composition Research Articles

Land use at different spatial scales alters the functional role of web-building spiders in arthropod food webs

Web-building spiders are abundant generalist predators in agroecosystems that primarily forage on insects including economically important pests. Local management and landscape composition influence spider and prey communities and thereby their trophic interactions and functional role in arthropod food webs. We compared predator-prey interactions between organically managed cereal fields and sown flower-rich fields, both supported by agri-environmental schemes. The surrounding landscape of twelve study sites differed in the percentage of arable crops within a radius of 500m around each site. We analyzed 1036 hand-collected web-building spiders with 5270 prey items from webs and 6777 potentially available prey items sampled by fenced suction sampling. Thysanoptera significantly dominated prey composition of web-building spiders in cereal fields located in landscapes with low percentages of arable crops, while Nematocera dominated prey composition in sown flower-rich fields. The captured prey numbers per spider web, irrespective of taxonomic identity, increased with the availability of potential prey, independent of habitat type or landscape composition. We did not find any effect on the compositions of web-building spiders and potential prey. Our results suggest that spider webs act as traps for prey that depend on prey density. However, this simple interpretation is only valid for the overall prey quantity, while capture success of single prey taxa may be habitat-specific and depend on landscape features. The impact of land use at different spatial scales on the functional role of web-building spiders should caution us towards density-based estimates of predation processes, e.g. when assessing the impact of agri-environmental schemes on arthropod food webs.

Testing the effects of ant invasions on non-ant arthropods with high-resolution taxonomic data.

Invasions give rise to a wide range of ecological effects. Many invasions proceed without noticeable impacts on the resident biota, whereas others shift species composition and even alter ecosystem function. Ant invasions generate a broad spectrum of ecological effects, but controversy surrounds the extent of these impacts, especially with regard to how other arthropods are affected. This uncertainty in part results from the widespread use of low-resolution taxonomic data, which can mask the presence of other introduced species and make it difficult to isolate the effects of ant invasions on native species. Here, we use high-resolution taxonomic data to examine the effects of Argentine ant invasions on arthropods on Santa Cruz Island, California. We sampled arthropods in eight pairs of invaded and uninvaded plots and then collaborated with taxonomic experts to identify taxa in four focal groups: spiders, bark lice, beetles, and ants. Spiders, bark lice, and beetles made up ~40% of the 9868 non-ant arthropod individuals sampled; the majority of focal group arthropods were putatively native taxa. Although our results indicate strong negative effects of the Argentine ant on native ants, as is well documented, invaded and uninvaded plots did not differ with respect to the richness, abundance, or species composition of spiders, bark lice, and beetles. One common, introduced species of bark louse was more common in uninvaded plots than in invaded plots, and including this species into our analyses changed the relationship between bark louse richness vs. L. humile abundance from no relationship to a significant negative relationship. This case illustrates how failure to differentiate native and introduced taxa can lead to erroneous conclusions about the effects of ant invasions. Our results caution against unqualified assertions about the effects of ant invasions on non-ant arthropods, and more generally demonstrate that accurate assessments of invasion impacts depend on adequate information about species identity.

Bahasa Indonesia

Spiders are the main predators in paddy ecosystem. Application of entomopathogenic fungus, such as Beauveria bassiana (Balsamo) is not expected to have any negative effect on spiders in the paddy field. This research was aimed to compare species composition, abundance, and species richness of spiders in ratoon paddy. The research was done on three hectares of rice fields that were treated with the following treatment, (i) 2 L/ha/application of liquid B. bassiana, (ii) 2 L/ha/application compost extract (without liquid B. bassiana), and (iii) a combination of liquid B. bassiana and compost extract with each using the same 2L/ha/application dose. The result of this research showed that B. bassiana bioinsecticide application did not affect the abundance and species richness of spiders in ratoon paddy. The treatments did not significantly affect species richness and abundance of the canopy-inhabiting spiders. The species richness and abundance of the soil-dwelling spiders on the paddy field applied by the bioinsecticide was not different from those without the bioinsecticide. The treatments did not effect species composition of the canopy-inhabiting and the soil-dwelling spiders. Application of B. bassiana bioinsecticide was not harmful for the spiders in the rice field.

The time scale of isotope signals in spiders: molting the remains of a previous diet

AbstractStable isotope analysis (SIA) has emerged as an important tool for understanding consumer diets and diet shifts. However, although the general idea behind SIA is clear, the interpretation of data is often fraught with problems because tissue turnover and fractionations are not known. We investigated shifts in stable isotope composition of spiders following a diet shift, using mealworms fed either maize (C4) or wheat (C3) flour. Mealworms had different carbon isotope composition depending on their diet and this difference was reflected in spider body parts. In the experiment, we first fed the spiders on a diet of either maize‐fed or wheat‐fed mealworms and then switched diet at the time of the second molt. Spiders were then sampled repeatedly until the next molt. We sampled both legs and abdomens, as these are presumed to have different turnover of tissue, and also molt remains were sampled when this was relevant. The data indicated that the spider legs had a turnover of about 20 days, whereas the spider abdomens had a turnover of about 8 days. Molt remains had the slowest turnover and reflected the diet at the previous molt, when the exoskeleton was formed. Both these observations indicate that SIA may be successfully used for elucidating diet shifts. More problematic was the fact that fractionation of carbon isotope ratios varied with body parts and diets. When spiders were fed maize‐mealworms then the fractionation was larger for abdomens, but when the spiders were fed wheat‐mealworms then the fractionation was larger for legs. The mechanisms underlying this pattern are unclear and deserve further attention.

Interactive effects of fire and large herbivores on web-building spiders.

Altered disturbance regimes are a major driver of biodiversity loss worldwide. Maintaining or re-creating natural disturbance regimes is therefore the focus of many conservation programmes. A key challenge, however, is to understand how co-occurring disturbances interact to affect biodiversity. We experimentally tested for the interactive effects of prescribed fire and large macropod herbivores on the web-building spider assemblage of a eucalypt forest understorey and investigated the role of vegetation in mediating these effects using path analysis. Fire had strong negative effects on the density of web-building spiders, which were partly mediated by effects on vegetation structure, while negative effects of large herbivores on web density were not related to changes in vegetation. Fire amplified the effects of large herbivores on spiders, both via vegetation-mediated pathways and by increasing herbivore activity. The importance of vegetation-mediated pathways and fire-herbivore interactions differed for web density and richness and also differed between web types. Our results demonstrate that for some groups of web-building spiders, the effects of co-occurring disturbance drivers may be mostly additive, whereas for other groups, interactions between drivers can amplify disturbance effects. In our study system, the use of prescribed fire in the presence of high densities of herbivores could lead to reduced densities and altered composition of web-building spiders, with potential cascading effects through the arthropod food web. Our study highlights the importance of considering both the independent and interactive effects of disturbances, as well as the mechanisms driving their effects, in the management of disturbance regimes.

English

The present study was an attempt to assess and evaluate the distribution, diversity and occurrence of spider community in Gulmarg Wildlife Sanctuary. India has 59 of the 110 spider families and at least, 1442 formally described species of the 39,000 known worldwide. Documenting spider assemblages assumes greater importance in the context of current rate of loss and degradation of forests which is known to have detrimental effect on many invertebrate groups. In order to assess the diversity and distribution of spiders at four sites during the months of May, June, July, October and December 2012, standard protocol was used to collect the spider community across the study area. The spider community was found to be represented by 18 taxa. Araneidae was dominant family followed by Lycosidae, Linyphiidae, Pholcidae, Salticidae, Sparassidae and Clubionidae. Differences in vegetation cover or human use showed variation in diversity and composition of spiders between different sites. Forest sites showed relatively higher diversity as compared to meadow sites. Key words: Spider community, diversity, Araneidae, Gulmarg.

Importance of core and linear marsh elements for wetland arthropod diversity in an agricultural landscape

Abstract The importance of linear habitat elements connecting core habitat patches for biodiversity conservation is still poorly understood. We surveyed reed strips along drainage ditches and reed marshes in an agricultural landscape to assess how both the density of linear habitat elements and the area of core habitat affect diversity and community composition of spiders, ground beetles, and long‐legged flies. For each taxonomic group, species composition of both ‘all’ and ‘typical wetland’ species, but not species richness was different between ditches and marshes. Overall local species richness and richness of species of conservation interest were affected at a landscape scale both by the density of ditches and by the area of core wetland. Strength and direction of these effects differed among groups. An increase in the density of reed ditches positively affected the total species richness of spiders and ground beetles and the species richness of typical wetland ground beetles, but not for long‐legged flies and typical wetland spiders. The positive effects were explained by improved network functionality, rather than by increase in available habitat area at landscape level. The number of red list spiders and long‐legged flies increased only with increasing core wetland area, while no significant effects were found for the number of red list ground beetles. Our study revealed that preserving or increasing the density of habitat corridors (more reed ditches) can be beneficial for the species richness of particular predatory arthropods, including species of conservation concern (especially ground beetles). Other groups react indifferently or are only positively impacted by an increase of core wetland area.

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.

Arthropod diversity in pristine vs. managed beech forests in Transcarpathia (Western Ukraine)

Pristine forests are generally assumed to be biodiversity hotspots. Is management detrimental to biodiversity? In some of the last European remains of pristine beech forest in Transcarpathia (Western Ukraine) the influence of forest management on arthropod biodiversity was assessed. Pitfall and flight interception traps were used to compare species numbers, abundances, Simpson diversity and species composition of beetles, spiders, millipedes and centipedes in pristine and managed forests.For the sum of all identified species and most taxonomic groups, species numbers and Simpson diversity were not significantly different between the two management regimes. Species numbers, abundances, and species composition of different beetle families, spiders, millipedes and centipedes differed more between the three regions (Jaremcha, Mala Uholka, Shyrokyj Luh) than between pristine and managed forest plots within the same region. Neither red-listed beetle species nor specialized saproxylic beetles were more diverse in pristine forests. But the latter were more abundant in pristine plots, where the amount of dead wood was up to twenty times higher than in the managed plots.We conclude that biodiversity in pristine beech forests is not generally higher than in managed beech forests. However, the much higher amount of dead wood in pristine forests provides a source habitat for saproxylic species spreading into managed forest plots in the same region, but not to distant forests, far from virgin forests, such as in Western Europe.

Is there a bottom-up cascade on the assemblages of trees, arboreal insects and spiders in a semiarid Caatinga?

Predator–prey dynamics regulate the community structure of arthropods and may be affected by changes in their habitat. Bottom-up effects influence the distribution of arboreal insects changing, in turn, the availability of resources and shelter for the spider assemblage. This study examines the effect of habitat structure (tree richness and density) on the assemblages of herbivorous insects and spiders along a gradient of secondary forest succession in a semiarid Caatinga in northeastern Brazil. Insect and spiders were collected by beating the foliage during dry and wet seasons in 2010 and 2011. Plant richness and density varied significantly among stages of succession. In total, 2,590 arboreal insects were collected, corresponding to 14 orders and 151 morphospecies. In addition, we sampled 896 canopy spiders, encompassing 14 families and 53 morphospecies. Insect richness and abundance were negatively related with habitat structure, while spider richness increases with tree richness. We did not find any relationship among insects and spiders but there were differences in species composition of insects among all successional stages, determined by changes in vegetation structure. However, this effect does not extend to the species composition of spiders that remain similar in the different stages of secondary succession. We conclude that habitat structure had a partial bottom-up effect on arboreal insects and spider assemblages, indicating that this factor regulates the richness, abundance and species composition of arboreal insets and species richness of spiders. Thus, habitat structure promotes the maintenance of insects and spider diversity in fragments of Caatinga.

The effect of thinning on ground spider diversity and microenvironmental factors of a subtropical spruce plantation forest in East Asia

Currently, information about the effect of forest management on biodiversity of subtropical plantation forests in Asia is quite limited. In this study, we compared the spider community structures and guild compositions of subtropical Cryptomeria japonica plantation forests receiving different degree of thinning (0, 25 and 50 %) in central Taiwan. The ground spider diversities and environmental variables were sampled/measured once every 3 months for 1 year before thinning and 2 years after thinning. Results showed that before thinning spider compositions did not differ significantly among three plantation forest types. Two years after thinning, spider species and family compositions of three plantation forest types differed significantly. In all three plantation forest types, the spider composition differed from year to year, indicating existence of temporal variations in spider diversity. Ground hunters (increased 200–600 % in thinned forests), sheet web weavers (increased 50–300 % in thinned forests) and space web weavers (decreased 30–50 % in thinned forests) were the major contributors of the observed spider composition differences among plantation forests receiving different treatments. The stands receiving thinning treatments also had higher illumination, litter decomposition rate, temperature and understory vegetation density. Thinning treatments might have changed the structures of understory vegetation and canopy cover and consequently resulted in abundance and diversity changes of these guilds. Moreover, the heterogeneity in understory vegetation recovery rate and temporal variation of spider composition might further generate spider diversity variations in subtropical forests receiving different degree of thinning.

Richness and composition of spiders in urban green spaces in Toledo, Ohio

Urbanization negatively affects biodiversity by increasing disturbance and habitat fragmentation. We compared three different urban habitats (vacant lots, gardens and forests) to examine differences in spider communities. We selected four sites of each habitat type and sampled spiders with pitfall traps. We collected a total of 547 individuals from 19 families. The most common families were Lycosidae, Corinnidae, Liocranidae, Cybaeidae, and Dictynidae. Spider activity-density overall and for males and females was higher in vacant lots than in forests, and female spiders had greater activity-density in gardens than in forests. Observed species richness did not differ with habitat type. Spider family composition differed significantly between urban habitat types, female morphospecies composition differed in forests and gardens and male morphospecies composition differed in forests and lots. The site characteristics differed significantly with habitat, and these habitat differences explained a large fraction (53.3% to 90.9%) of the variation in composition and richness. Yet, bare ground was the only factor that significantly correlated with declines in female richness. Thus, spider communities, aspects of specifically activity-density and composition, differ between habitats in urban green spaces with potentially important implications for conservation and trophic interactions within urban areas.

Richness and composition of spiders in urban green spaces in Toledo, Ohio

Urbanization negatively affects biodiversity by increasing disturbance and habitat fragmentation. We compared three different urban habitats (vacant lots, gardens and forests) to examine differences in spider communities. We selected four sites of each habitat type and sampled spiders with pitfall traps. We collected a total of 547 individuals from 19 families. The most common families were Lycosidae, Corinnidae, Liocranidae, Cybaeidae, and Dictynidae. Spider activity-density overall and for males and females was higher in vacant lots than in forests, and female spiders had greater activity-density in gardens than in forests. Observed species richness did not differ with habitat type. Spider family composition differed significantly between urban habitat types, female morphospecies composition differed in forests and gardens and male morphospecies composition differed in forests and lots. The site characteristics differed significantly with habitat, and these habitat differences explained a large fraction (53.3% to 90.9%) of the variation in composition and richness. Yet, bare ground was the only factor that significantly correlated with declines in female richness. Thus, spider communities, aspects of specifically activity-density and composition, differ between habitats in urban green spaces with potentially important implications for conservation and trophic interactions within urban areas.

Assessment of the probability of colonization of local spider communities in an experimental landscape

Establishment of communities is a dynamic process initiated by immigration. Therefore, movements of individuals within a metacommunity are important for maintaining and increasing species distribution. We present results of a small landscape-level experiment that manipulated habitat size and diversity. We examined the rates of colonization of spider species, and the richness, abundance and composition of foliage-dwelling spiders. Estimation of colonization rates was based on maximum likelihood. The experimental landscape was composed of five blocks with four patches (two large, 1 m 2 ; two small, 0.25 m 2 ). Less diverse patches had seedlings of one plant species, whereas more diverse patches had four species with diverse structures. Eight periodic censuses of spiders arriving in the patches were performed (average interval between censuses, 28 days). The initial composition of colonizers was significantly different from the final composition, but rates of colonization did not differ between sizes and diversities, or their interaction. Abundances of spiders were positively influenced by patch size. Compositions in each temporal sample were determined by differences in the species pool migrating and arriving at an experimental landscape irrespective of habitat size or diversity. Larger patches were more likely to receive more colonists representing a wider array of species than small patches. The probability of colonization was independent of patch size and diversity, which contradicts theoretical predictions. The results highlight the high colonization capacity of spiders on spatial and temporal scales.

Reductions in downed deadwood from biomass harvesting alter composition of spiders and ground beetle assemblages in jack-pine forests of Western Quebec

Renewed interest in biomass harvesting has underscored the need for ecologically relevant thresholds and empirical validation of species responses for deadwood retention if biodiversity is to be preserved in managed landscapes. We experimentally reduced volumes of downed deadwood in clear cut jack-pine stands in Western Quebec, Canada and then monitored changes in spider and ground beetle assemblages 1 and 2-years following biomass removal as well as in uncut stands. We reduced volume of downed deadwood by (1) removing residual deadwood placed on machine corridors during the initial harvest of the stand to minimize soil compaction and (2) removing all residual deadwood material throughout the experimental plots. Ground beetle and spider assemblages from deadwood depleted plots were then compared with those in clearcut plots where no additional biomass had been removed and with uncut stands to assess the incremental effect of overstory removal and subsequent biomass removal using multivariate regression trees. We identified 13,822 individual arthropods representing 177 species. We observed differences in species assemblages attributable to the effects of overstory removal (35% of the explained variance) as well as biomass removal, particularly between plots with intensive removal of biomass and those with no additional or moderate removal of biomass (11% of the explained variance). As expected we observed a range of individual species response patterns. Of particular concern were species that experienced incrementally negative effects of overstory and biomass removal and those that were strongly promoted by biomass removal. These species showed responses atypical of those observed following clear cutting and may fall outside both the range of natural variability observed in this region as well as the range of current forest management intensity practiced in North America.

The habitat-specific effects of highway proximity on ground-dwelling arthropods: Implications for biodiversity conservation

The total length of highways worldwide has increased continuously over recent decades. Highways and their roadside verges may substantially affect species dispersal, and the ecological effects of highways often extend to neighbouring areas. This study investigated the effects of highways on assemblages of ground-dwelling arthropods in neighbouring forest and open habitats. In total, 24 sites within five highway segments situated in the Czech Republic were sampled using transects of pitfall traps placed at increasing distances (0, 50 and 100m) from the edge of highway verges. The total catch size and species richness of ground-dwelling spiders and beetles varied more strongly with distance from the highway edge in forest habitats than in open habitats. Species composition of both spiders and beetles was significantly affected by distance from the highway edge in open habitats as well as in forest habitats. In general, the species richness of forest specialist beetles (but not of spiders) was negatively affected by highway proximity in forested sites, whereas habitat generalists and open habitat specialists (both spiders and beetles) benefited from proximity to a highway in both forest and open habitats. Our results indicate that highway verges may potentially enhance local assemblages of ground dwelling spiders and beetles because they provide suitable sites (in intensively managed open landscapes) or dispersal corridors (in forested landscapes) for habitat generalists and open habitat specialist species. However, negative effects on forest specialists must also be considered, especially in landscapes with little forest. The landscape context should be given substantial consideration in future decisions about highway location because possible threats to forest specialists and benefits for other species must be recognised and balanced.

Arboreal spider assemblages associated with four tree species in the Grassland Biome of central South Africa (Arachnida: Araneae)

ABSTRACT Foliage-dwelling spiders (Arachnida: Araneae) were collected from four common tree species in the Grassland Biome of central South Africa by beat-sampling. The aim of the study was to assess possible differences in the assemblage structure and species composition of spiders that could be attributed to structural differences in the vegetation. In total, 1909 spiders representing 17 families and 54 species were collected. Four families were dominant in abundance, together accounting for more than 73% of the spider fauna: Miturgidae (23.1%) was most numerous, followed by Araneidae (17.7%), Thomisidae (16.7%) and Philodromidae (15.4%). Overall spider abundance and species richness did not differ significantly among the four tree species, decreasing slightly from Acacia karroo (n=495, 38 spp.) to Olea europaea africana (n=479, 32 spp.), Buddleja saligna (n=477, 36 spp.) and Searsia lancea (n=458, 37 spp.). However, significant seasonal differences were detected for each tree. Generally, abundance and species richness were lowest during winter and highest during summer on all four species. Our findings suggest that vegetative and habitat structure and complexity have a limited influence on the abundance and species richness of tree-dwelling spiders in grassland habitats, although these factors may affect the assemblage structure on different tree species.

Effects of experimentally planting non-crop flowers into cabbage fields on the abundance and diversity of predators

Flowery field margins and intersowing of crops with flowers are used as management practices to promote arthropod biodiversity as well as biocontrol agents. Positive effects of enhancement (in abundance and species richness) of hymenopteran parasitoids on control of Lepidoptera pests have previously been demonstrated. However, effects on predatory arthropods, which may also serve as pest control agents, remain unclear. In an experimental study in cabbage fields we tested how sown flower strips on field margins and intersowing with cornflower affected the species richness, abundance and community composition of ground beetles and spiders. Furthermore, we investigated whether effects of flower margins are dependent on the distance from the field margins. We found that field margins generally harboured higher species richness, whereas effects on abundance were weaker. Intersown cornflower had positive effects on spider and ground beetle abundance, but affected species richness only weakly. Our results do not provide evidence for effects of distance from the flowery field margins on predator richness or abundance. Species composition was strongly affected by the habitat management actions. We conclude that habitat management practices like flower strips on field margins and intersowing with flowers, which are primarily added to attract and enhance parasitoids for pest control, also benefit biodiversity conservation in spiders and ground beetles. They also positively affect the abundance of these primarily predatory taxa, which adds to the biocontrol potential of non-crop flowering plants.

Management intensity and vegetation complexity affect web-building spiders and their prey

Agricultural management and vegetation complexity affect arthropod diversity and may alter trophic interactions between predators and their prey. Web-building spiders are abundant generalist predators and important natural enemies of pests. We analyzed how management intensity (tillage, cutting of the vegetation, grazing by cattle, and synthetic and organic inputs) and vegetation complexity (plant species richness, vegetation height, coverage, and density) affect rarefied richness and composition of web-building spiders and their prey with respect to prey availability and aphid predation in 12 habitats, ranging from an uncut fallow to a conventionally managed maize field. Spiders and prey from webs were collected manually and the potential prey were quantified using sticky traps. The species richness of web-building spiders and the order richness of prey increased with plant diversity and vegetation coverage. Prey order richness was lower at tilled compared to no-till sites. Hemipterans (primarily aphids) were overrepresented, while dipterans, hymenopterans, and thysanopterans were underrepresented in webs compared to sticky traps. The per spider capture efficiency for aphids was higher at tilled than at no-till sites and decreased with vegetation complexity. After accounting for local densities, 1.8 times more aphids were captured at uncut compared to cut sites. Our results emphasize the functional role of web-building spiders in aphid predation, but suggest negative effects of cutting or harvesting. We conclude that reduced management intensity and increased vegetation complexity help to conserve local invertebrate diversity, and that web-building spiders at sites under low management intensity (e.g., semi-natural habitats) contribute to aphid suppression at the landscape scale.

Araneofauna (Arachnida: Araneae) en cultivos de algodón (<i>Gossypium hirsutum<i/>) transgénicos y convencionales en el norte de Santa Fe, Argentina

Spiders have considerable potential importance for their role as predators to some pests in agricultural systems. The composition of spiders in transgenic and conventional cotton at the Research Station of INTA Reconquista (Santa Fe) was studied during the 2005-2006 season. The experiment was a complete randomized block design with three replications and three treatments: transgenic Bt cotton (ALBt), conventional cotton without chemical control (ALCSC), and conventional cotton with chemical control (ALCCC). Weekly, spiders were collected using nets, vertical cloth and pitfall-traps. A total of 1255 specimens (16 families, and 32 species) were collected. Seven families were found in all the treatments, mainly Thomisidae (n=1 51, 84.04%) and Araneidae (n=83, 6.64%). The Hunting spiders guild ambushers (n=1053, 83.91%), "Orb weavers" (n=85, 6.77%) and "Stalkers" (n=53, 4.22%) were more abundant. There were no significant differences in the indexes diversity between treatments. Spiders were presented during the whole crop season, with peaks about flowering and boll maturity, with the highest abundance in ALBt. This work is part of the first set of data registered in Argentina about spider's community in cotton crops.