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Aim: Species distribution models (SDMs) have emerged as essential tools in the equipment of many ecologists, useful to explore species distributions in space and time and answering an assortment of questions related to biogeography, climate change biology and conservation biology. Historically, most SDM research concentrated on well‐known organisms, especially vertebrates. In recent years, these tools are becoming increasingly important for predicting the distribution of understudied invertebrate taxa. Here, we reviewed the literature published on main terrestrial arthropod predators (ants, ground beetles and spiders) to explore some of the challenges and opportunities of species distribution modelling in mega‐diverse arthropod groups. Location: Global. Methods: Systematic mapping of the literature and bibliometric analysis. Results: Most SDM studies of animals to date have focused either on broad samples of vertebrates or on arthropod species that are charismatic (e.g. butterflies) or economically important (e.g. vectors of disease, crop pests and pollinators). We show that the use of SDMs to map the geography of terrestrial arthropod predators is a nascent phenomenon, with a near‐exponential growth in the number of studies over the past ten years and still limited collaborative networks among researchers. There is a bias in studies towards charismatic species and geographical areas that hold lower levels of diversity but greater availability of data, such as Europe and North America. Conclusions: Arthropods pose particular modelling challenges that add to the ones already present for vertebrates, but they should also offer opportunities for future SDM research as data and new methods are made available. To overcome data limitations, we illustrate the potential of modern data sources and new modelling approaches. We discuss areas of research where SDMs may be combined with dispersal models and increasingly available phylogenetic and functional data to understand evolutionary changes in ranges and range‐limiting traits over past and contemporary time‐scales. [ABSTRACT FROM AUTHOR]

Although functional and phylogenetic diversities are increasingly used in ecology for a variety of purposes, their relationship remains unclear, and this relationship likely differs among taxa, yet most recent studies focused on plants. We hypothesize that communities may be diverse in functional traits due to presence of: many phylogenetic lineages, trait divergence within lineages, many species and random functional variation among species, weak filtering of traits in favorable environments, or strong trait divergence in unfavorable environments. We tested these predictions for taxa showing higher (ants), or lower (spiders, ground beetles) degrees of competition and niche construction, both of which might decouple functional traits from phylogenetic position or from the environment. Studying > 11,000 individuals and 216 species from coastal heathlands, we estimated functional as minimum spanning trees using traits related to the morphology, feeding habits and dispersal, respectively. Relationships between functional and phylogenetic diversities were overall positive and strong. In ants, this relationship disappeared after accounting for taxonomic diversities and environments, whereas in beetles and spiders taxonomic diversity is related to functional diversity only via increasing phylogenetic diversity. Environmental constraints reduced functional diversity in ants, but affected functional diversity only indirectly via phylogenetic diversity (ground beetles) and taxonomic and then phylogenetic diversity (spiders and ground beetles). Results are consistent with phylogenetic conservatism in traits in spiders and ground beetles. In ants, in contrast, traits appear more phylogenetically neutral with any new species potentially representing a new trait state, tentatively suggesting that competition or niche construction might decouple phylogenetics from trait diversity. [ABSTRACT FROM AUTHOR]

Conservative biological control promotes the use of native natural enemies to limit the size and growth of pest populations. Although spiders constitute one of the most important groups of native predators in several crops, their trophic ecology remains largely unknown, especially for several generalist taxa. In laboratory, we assessed the predatory behaviour of a wandering spider (the wolf spider Lycosa thorelli (Keyserling, 1877) against several arthropods varying in size and trophic positions, all found in South American soybean and rice crops. As prey we used the bug Piezodorus guildinii (Westwood, 1837) as well as larvae and adults of the moth Spodoptera frugiperda (Smith, 1797), both being considered important pests in Uruguayan crops. We also used several non‐pest arthropods as prey, sarcophagid flies, carabid beetles and wolf spiders. All prey were attacked in more or less high, although not statistically differing, proportions. However, carabids were not consumed, and bugs were consumed in significantly lower proportions than flies. A negative correlation was found between prey size and acceptance rate. Immobilization times were longer against larvae when compared to moths and flies, while predatory sequences were longer for bugs when compared to flies, moths and spiders. In addition, we found a positive effect of prey size on predatory sequence length and complexity. Our results confirm the ability of spiders to attack and feed upon prey with different morphologies, included well‐defended arthropods, and their potential use as natural enemies of several pests in South American crops. [ABSTRACT FROM AUTHOR]

In spite of their highly patchy distribution, the effects of landscape configuration on specialist biodiversity has been little studied in salt marshes. We investigated the impact of patch size on the abundance of specialist arthropods in two contrasted salt-marsh environments. Dominant ground-active species were sampled by pitfall traps in increasing areas of natural vegetation (dominated by Atriplex portulacoides) along two transects surrounded by either grazed (dominated by Puccinellia maritima) or invasive (dominated by Elymus athericus) vegetation. Spatially- and temporally-replicated sampling took place in the Mont Saint-Michel Bay (Western France) during 2012. Three dominant species, the wolf spider Pardosa purbeckensis (Araneae, Lycosidae), the ground beetle Pogonus chalceus (Coleoptera, Carabidae) and the beach-hopper Orchestia gammarellus (Amphipoda, Talitridrae), constituted 96% of all arthropods caught (N = 66,299). Patch size only had an effect on the carabid and on the amphipod, with large patches more populous than small ones, reinforcing the idea that the effects of fragmentation are stronger for species with limited mobility. Environment had a significant effect on the population density of all species, with systematically more individuals in patches surrounded by invaded than by grazed salt marshes, which confirms the particularly negative impact of over-grazing on salt-marsh biodiversity. This study finally suggests that both invasive species and grazing impact salt-marsh biodiversity also at a landscape scale. • The effects of landscape on arthropods has been little studied in salt marshes. • The response of populations to fragmentation was assessed for 3 dominant species. • Patch size of natural vegetation had an effect on low-mobility species only. • More individuals were found in patches surrounded by invaded than by grazed marshes. • Results suggest that disturbances impact arthropods also at a landscape scale. [ABSTRACT FROM AUTHOR]

Copyright of Basic & Applied Ecology is the property of Urban & Fischer Verlag and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Despite the expected increase in extreme flood frequency, the manner in which terrestrial arthropods cope with regular submersion of their habitat remains poorly understood in meadows, especially in temperate floodplains. Here, we studied the recolonization dynamics of arthropods after a severe spring flood in the Loire Valley (France). We carried out analyses at the community (order or family identification level) and species scales, focusing on the assemblages of two dominant and diverse groups: carabids and spiders. Our objectives were the following: (i) to describe the temporal changes in community structure after flooding and (ii) to assess the influence of landscape configuration on recolonization patterns of species and their functional traits. Fieldwork was performed along three sampling transects, by using 75 pitfall traps, in 2012. A total of 14 767 arthropods belonging to 87 families were trapped, including 5538 spiders (55 species) and 3396 carabids (66 species). Multivariate analyses discriminated assemblages from flooded and non-flooded habitats and revealed changes over time in arthropod families and species after flood withdrawal. In particular, wolf spiders (Lycosidae) were the first to recolonize, whereas other groups clearly avoided flooded sites. Our results also revealed that short distances to hedgerows, and to a lesser extent, distance to woodlands, favoured the recolonization of large and ground-running spiders. In conclusion, our study shows the short-term resilience of certain groups or stenotopic species toflooding and also the relevance of multi-taxon-based studies. The presence of hedgerows has to be considered carefully in management plans because of their role of refuge during flooding. [ABSTRACT FROM AUTHOR]

Highlights: [•] Grassland mowing had negative effects on carabids in the long- and on spiders in the short-term. [•] Cutting date in itself had few effects on spiders and carabids. [•] Even late dates were deleterious for ground-dwelling arthropods. [ABSTRACT FROM AUTHOR]

During the last decades, urban consolidation has been developed to minimize spatial expansion of cities, yet very few studies investigated whether it would actually reduce some negative effects of urbanization on biodiversity. In this study, we compared the invertebrate assemblages associated with two distinct urban forms (compact vs. conventional), focusing on two arthropod taxa often used as bioindicators, and dominant in urban habitats: spiders and carabid beetles. The following parameters were estimated: assemblage composition, species richness, activity-density total, per species (excluding seldom-recorded species) and per size class. The field collection was performed in 2009 using pitfall traps randomly set in hedgerows within 6 sites (representing 251 traps). A total of 4,413 spiders belonging to 117 species and 2,077 adult carabid beetles belonging to 39 species were collected. We found few significant differences in carabid beetle and spider assemblages between the two urban forms. The species richness of both groups was independent from the neighborhood design. Only four species of carabid beetles and ten of spiders significantly reacted to the neighborhood design, and no difference was found among the two designs for all other species. Large carabid beetles were more abundant and small spiders less abundant in the new neighborhood design compared to the conventional one. For both carabid beetles and spiders, no difference in assemblage composition was found between neighborhood designs. We therefore conclude that urban consolidation, by permitting a higher human density with similar arthropod assemblages, could contribute to reduce biodiversity loss in cities. [ABSTRACT FROM AUTHOR]

Urbanization creates human disturbance that plays an important role in ecosystem dynamics. Most of the time, there is a time lag between disturbance and colonization. Opportunistic species with high dispersal power colonize first, while habitat specialist species with a lower power of dispersal colonize later; the communities change with time after disturbance. We hypothesize that, following the establishment of a new neighbourhood, arthropod communities will change from habitat generalists to specialists, and will be more similar to those of the adjacent countryside. We selected two groups of invertebrates often used as bioindicators, spiders and carabid beetles. The following parameters were estimated: assemblage composition, species richness, activity-density total and per life history trait (broad habitat preference). The field data were collected in 2010 within 3 towns located in France. Neighbourhoods of 10 and 30 years old were pair-matched in these towns and sampled using pitfall traps set randomly in hedgerows (120 traps in total). 2101 adult spiders belonging to 89 species were collected, whereas the 643 captured carabid beetles belonged to 24 species. We found no evidence of any significant change in carabid beetle and spider communities according to neighbourhood age. The assemblages were mainly composed of habitat generalist species. These results suggest that urban areas can be seen to be in continual state of disruption, and colonization of these areas is assumed to be relatively rapid (i.e., less than 10 years in our case study), although incomplete. [ABSTRACT FROM AUTHOR]

The urbanization process is the motor of deep environmental changes at both local and landscape levels. Although more and more studies are investigating the ecological consequences of urbanization, only a few have studied small-scale responses of biodiversity to urban-rural boundary gradients, and even fewer have compared different model groups synchronically. In this study, we compared the responses of two invertebrate groups often used as bioindicators, spiders and carabid beetles, along small-scale boundaries (around 1 km). The following parameters were estimated: assemblage composition, species richness, and activity-densities overall and per life history trait (habitat preference, dispersal abilities for carabid beetles and hunting guilds for spiders). The field data were collected in 2009 using pitfall traps set randomly in hedgerows within urban, boundary and rural zones (30 traps in total). 924 adult spiders belonging to 78 species were collected, whereas the 330 captured carabid beetles belonged to 25 species. We found no evidence of any significant change in carabid beetle activity-density (overall and for most life history traits) or in species richness along the urban-rural gradient. Conversely, there was a significant change in spider activity-density, both per habitat preference and per hunting guild. We also found a progressive change in community composition for spiders. Our results suggest that studying different model groups can provide complementary information about urbanization. [ABSTRACT FROM AUTHOR]

As a result of an invasion by the native grass Elymus athericus (Link) Kerguélen (Poaceae) in the last 10 years, a major change in vegetation cover has occurred in salt marshes of the Mont Saint-Michel bay, Western France. The impact of such an invasion on carabid assemblages, a dominant group of terrestrial arthropods in these habitats and containing several stenotopic species, is investigated here. In our study site, carabid data are available from 1983 and 1984, allowing a comparison of species distribution ranges in salt marshes before (1983-1984) and after (2002) the E. athericus invasion. A total of 16,867 adults belonging to 40 species were caught. By considering the presence-absence of species shared between studies, we show that the invasion by E. athericus promoted the progression of non-coastal species (mainly Pterostichus s.l. spp.). This did however not interfere with resident species distributions, finally resulting in higher carabid species richness in the entire area. The species composition and abundances of carabid assemblages were also compared between natural and invaded stations in 2002. The main result is that abundances of some halophilic species decreased in one invaded plot (in case of Pogonus chalceus (Marsham 1802)) whereas the opposite pattern was observed for other species (e.g., Bembidion minimum (Fabricius 1792)). Invaded habitats were characterized by lower percentages of halophilic species and higher total species richness. [ABSTRACT FROM AUTHOR]

Copyright of Basic & Applied Ecology is the property of Urban & Fischer Verlag and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Highlights • The impact of local vs. landscape on arthropod assemblages in remains little studied. • 24,726 carabids were sampled in 20 fields along gradient a OF in the landscape. • Local vs. landscape characteristics differentially shaped carabid assemblages. • Organic farming was also important in determining emerging and circulating species. Abstract Knowledge of biodiversity in agroecosystems is crucial for understanding ecosystem functioning, but requires accurate sampling methods. Most studies of ground-active arthropods in fields rely on activity-density measurement using pitfall traps. Assemblages locally observed are likely to composed both resident and immigrant species, and that is especially true for arthropods exhibiting high dispersal abilities and/or larval development that is very different from the adults. Using a spatially paired design of emerging traps vs pitfall traps in 10 pairs of organic (OF) and conventional (CF) fields, we quantified how circulating and emerging assemblages of an abundant taxa of mobile and holometabolous insects, carabid beetles, were impacted by different field farming systems and landscape characteristics. Field sampling was carried out during 5 months of 2015 in Brittany (Western France), during which 24,726 individuals belonging to 85 species were captured. Our results revealed that the number of individuals and species of both emerging and circulating assemblages were significantly higher in OF compared to CF, reinforcing the idea that OF provide more suitable conditions for both resident and mobile arthropods. Landscape and local factors had a similar influence on emerging carabid assemblages, whereas local factors were stronger drivers for circulating carabid assemblages. This study highlights the importance of distinguishing resident (emergent) and mobile (circulating) individuals when assessing the differential role of local vs. landscape factors in community assembly. It also reinforces the idea that spatiotemporal movements of predatory arthropods are impacted by spillover from and between croplands, resulting in source-sink dynamics with habitat quality being the major driver of these processes. [ABSTRACT FROM AUTHOR]

Despite the role generalist predators may play in biological regulation, the influence of landscape composition in shaping their assemblages remains little studied, especially when landscape interacts with local factors. In this study, we investigated the effects of farming systems along gradients in landscape elements on the structure and composition of carabid and spider assemblages. Twenty pairs of organic vs. conventional spatially-matched fields were sampled in 2013 along increasing percentage covers of organic farming and semi-natural habitats in the landscape. A total of 24241 spiders and 27767 carabids belonging to 120 and 75 species respectively were collected by pitfall traps. Farming systems locally had a strong influence on the community structure (activity-density and species richness) and composition for both spiders and carabids. Structure of spider assemblages was mostly affected by local and landscape factors, whereas that of carabids was more driven by landscape variables and the interaction of the two levels. Spider and carabid community compositions were mostly determined by field farming systems and wood percentage around the field. Our study underlines the importance of landscape context in shaping assemblages of predatory arthropods, and suggests that mechanisms behind the distribution of individual species strongly differ between spiders and carabids. [ABSTRACT FROM AUTHOR]