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Simple Summary: Turfgrass is a prevalent ground cover type within urban areas, and is found on large swathes of commercial, residential, and recreational land. Turfgrass supports low biodiversity compared with more diverse vegetation communities. One increasingly popular method for supporting arthropod communities in urban areas is to plant wildflowers in available spaces using a commercial seed mix, which can support beneficial insects such as butterflies, bees, and natural enemies. However, the long-term impacts of these wildflower habitats on arthropod communities in turfgrass systems is poorly known. To explore this, we used pan traps to sample insects from turfgrass systems adjacent to wildflower plots over three years and quantified how different insect groups changed in abundance. We found that different insect groups had variable changes in abundance over time, with sweat bees (Halicitdae) and skipper butterflies (Hesperiidae) being less abundant two years after wildlife implementation, and predatory flies showing boosted abundance for two years post-implementation. These results point to the complex dynamics of arthropod communities in turfgrass systems following wildflower implementation and the need to study how to best maintain these habitats to support long-term biodiversity. Urbanization is rapidly influencing the abundance and diversity of arthropods. Within urban systems, managed turfgrass is a prominent land cover which can support only a limited number of arthropod groups. To allow for more arthropod biodiversity and to support beneficial insects within turfgrass, increasing numbers of land managers are choosing to partially convert turf habitat to wildflower habitat using commercially available seed mixes. However, the population dynamics of arthropod groups in these systems are poorly known, with consequentially little information on best long-term practices for managing wildflower habitats in turfgrass systems. To address this gap, we sampled insects using pan traps in turfgrass systems pre- and post-implementation of wildflower habitats and examined the change in abundance of several insect families and functional guilds. Insect groups had variable responses to wildflower habitat implementation, with some groups such as sweat bees and skipper butterflies showing a decline two years post-implementation. Other groups, such as predatory flies, were relatively more abundant one and two years post-implementation. These variable responses point to the need for more research on the long-term effects of wildflower habitats on beneficial insects in turfgrass habitats. [ABSTRACT FROM AUTHOR]

Arthropods are declining globally, and entomologists ought to be in the forefront of protecting them. However, entomological study methods are typically lethal, and we argue that this makes the ethical status of the profession precarious. Lethal methods are used in most studies, even those that aim to support arthropod conservation. Additionally, almost all collecting methods result in bycatch, and a first step toward less destructive research practices is to minimize bycatch and/or ensure its proper storage and use. In this review, we describe the available suite of nonlethal methods with the aim of promoting their use. We classify nonlethal methods into (a) reuse of already collected material, (b) methods that are damaging but not lethal, (c) methods that modify behavior, and (d) true nonlethal methods. Artificial intelligence and miniaturization will help to extend the nonlethal methodological toolkit, but the need for further method development and testing remains. [ABSTRACT FROM AUTHOR]

The galling insects, host plants and all gall-interacting organisms may depend on environmental conditions and stochasticity to establish and maintain their life cycles and trophic interactions. The micromoth Palaeomystella oligophaga (Lepidoptera: Momphidae) induces galls on Macairea radula (Melastomataceae) and its populations suffer mortality caused by direct and indirect negative interactions. Herein, we hypothesized that (i) the occurrence of galls should be greater during the dry period, when arthropods may depend more on microhabitats during the larval stage. However, (ii) P. oligophaga can face different kinds and frequencies of enemies during different cycles of the year. In addition, (iii) stochastic events such as fire may reduce the occurrence of natural enemies and thus increase the galling insects frequency. We quantified the galling insect survival rates, the proportion and kinds of natural enemies for 16 months (February 2017 – May 2018), detecting two life cycles of these gall-inducing insects by year. We analyzed galls in these 2 cycles and 1 cycle in the second year after a fire event. We confirmed the bivoltine cycle of P. oligophaga, with more galls induced during the first cycle (Feb – May) but with a higher frequency during the second cycle (Aug-Oct), following the post-fire period (Feb – May). The survival rates of P. oligophaga were higher during the post-fire cycle compared to the same period of the previous year, but lower than during the second. The enemies were more abundant during the first cycle. The bivoltine life cycle may constitute a strategy for P. oligophaga to use the galls during different periods of the year because the maturation and emergence of adults depend on the fluctuation of the occurrence of enemies, which varies according to abiotic conditions. Furthermore, this strategy offers shelter and food resources to all other organisms whose life cycles are synchronized with the availability of this microhabitat. [ABSTRACT FROM AUTHOR]

Coconut crabs Birgus latro have recently been reclassified from Data Deficient to Vulnerable on the IUCN Red List. This is a somewhat unusual case of temporal and spatial information being used to change the IUCN status of an arthropod and it draws attention to the paucity of biological data on most invertebrate species. To be listed, two or more scientific criteria need to be documented but such data are unavailable for many invertebrates. This raises the question as to whether certain invertebrates receive more scientific attention and are hence more likely to be listed if, like the coconut crab, they are large, slow-reproducing or a dual-biome species (characteristics which make them inherently vulnerable) and whether being an indicator or a flagship species is important. [ABSTRACT FROM AUTHOR]

Natural forests are important for terrestrial biodiversity conservation. In South Africa, many forest patches are naturally small and surrounded by either natural grassland or exotic plantations., Here we compared arthropod diversity and composition among natural forest patches, pine plantations and grassland. We also assess how arthropod assemblages respond to the environmental changes at the boundaries between natural forest patches and the two different surrounding vegetation types., Twenty transects were selected, ten natural forests surrounded by pines, and ten natural forests surrounded by natural grassland. Transects ran from natural forest interiors, across the boundary into the interior of the surrounding vegetation. Arthropods were sampled using pitfall traps and active searches., Natural forests surrounded by grassland had higher species richness than those surrounded by pines. Greater arthropod abundance was in grassland edges than other stations. Pairwise comparisons revealed significant differences in assemblages between all vegetation types. This implies that forest biodiversity in these patches is altered by the main vegetation type in the matrix or in close proximity. Qualitative differences in assemblages between natural forest-grassland boundaries were greater than differences between natural forest-pine boundaries, indicating greater sharing of species between pines and natural forests., Our findings emphasise the value of natural forest-grassland edges for conserving arthropod diversity as they add to the local species pool. Overall, we show that when maintaining small isolated natural forest patches, the role of the surrounding vegetation must be considered as it has a major influence on the local patch fauna. [ABSTRACT FROM AUTHOR]

Soil compaction is a major threat to natural resources. However, little information is available on the impacts of soil compaction on arthropod diversity especially relative to different types of vegetation, land use and restoration activities. In response to this dearth of information, we studied soil compaction, as well as percentage soil moisture and mean leaf litter depth, associated with four vegetation types: natural vegetation (fynbos, the historic condition), agricultural land (vineyards), invasive alien trees, and vegetation cleared of invasive alien trees (recovering vegetation). Our study took place in the Cape Floristic Region, South Africa, a biodiversity hotspot, yet also an area of intense viticulture and heavy invasion by alien plants. We sampled soil surface-active arthropods using pitfall traps, and compared species richness and abundance in different vegetation types with various levels of soil compaction and other soil variables. Overall, vineyards had the highest soil compaction while natural fynbos and aliens had low and comparable compaction. For both arthropod species richness and abundance, the order of the four vegetation types was, from highest to lowest: natural fynbos, alien cleared sites, vineyards, and alien infested sites. Level of soil compaction negatively correlated with arthropod species richness but not with abundance. Neither soil moisture nor leaf litter depth on their own significantly affected arthropod species richness or abundance. While alien trees overall had a strong negative effect on both arthropod species richness and abundance, and much more so than vineyards, the situation is reversible, with removal of aliens being associated with rapid recovery of soil structure and of arthropod assemblages. This is an encouraging sign for restoration. [ABSTRACT FROM AUTHOR]

Large-scale ecological networks (ENs) are an important mitigation measure in agriculturally transformed landscapes. However, understanding the multitude of pressures influencing the presence/absence of species, and subsequent degree of species spatial heterogeneity, is important when planning effective ENs. We aim here to measure these pressures and determine species heterogeneity in ENs against natural reference sites. We use arthropods, as they are effective bioindicators for measuring these pressures and heterogeneity, as many are habitat sensitive. Here we use many arthropod taxa to determine how a suite of variables influences the spatially sensitive grassland interior species of both EN corridors and protected areas (PAs). At each of 48 selected sites, nine stations were sampled for arthropods, with six stations in plantation block (i.e. transformed grassland) or natural indigenous forest, as well as associated edge zone and three stations in EN corridor or PA interior. Eleven variables were measured and classed into environmental, design, and current and historical management variables. Data were split into: overall data, recording all species found in interior zones, and datasets containing only species that had >50 or >75 % of their abundance sampled in the interior zone. These datasets were split into total species and singleton-removed datasets. Overall, the richness of non-singleton species, i.e. those frequently sampled in grassland interiors, were most responsive to natural background environmental variables, while design and management variables were most important for datasets with singletons retained. This means that when planning ENs, we first need to conserve the natural range of environmental heterogeneity to conserve a range of interior specialists. This natural spatial heterogeneity then needs to be incorporated into design and management planning to conserve the full range of biodiversity in ENs, as if in PAs. [ABSTRACT FROM AUTHOR]

The woodlouse genus Halophiloscia Verhoeff, 1908 includes littoral halophilous species distributed along the coasts of the Mediterranean Sea, the Atlantic coasts of Europe and northern Africa. The species Halophiloscia couchii has been introduced to the Americas, Hawaii and Australia. The Canary Islands harbour four species, two of which are included in catalogues of endangered species., One mitochondrial and one nuclear gene sequenced from over 100 specimens, including outgroups, were analysed to infer the colonisation and diversification processes of Halophiloscia in the Canary Islands and shed light on their conservation status., The Canary Islands were independently colonised by three distinct Halophiloscia lineages: (i) the endemic species H. rodriguezi, collected in several western Canary Islands, and the troglobiomorphic H. microphthalma from La Palma, (ii) the endemic H. canariensis, found throughout the eastern Canaries, and (iii) the cosmopolitan H. couchii, present on Gran Canaria and Tenerife., Halophiloscia microphthalma is not sister to the extant epigean Halophiloscia species present on the same island, which together with the low levels of genetic variability detected in the species may warrant a higher conservation status than presently given., The mitochondrial marker revealed a fine-scale phylogeographic structure in H. canariensis, and rejected recent sharp declines in its population size, which in addition to its widespread distribution challenge its consideration as an endangered species., The presence of H. couchii in the archipelago is interpreted as a recent introduction. Although no evidence of introgression was detected, more thorough sampling and monitoring of introduced populations are recommended to discard either hybridisation or competitive displacement of native species. [ABSTRACT FROM AUTHOR]

1. Spiders often dominate predator assemblages in vineyard agroecosystems. Land-use practices that enhance their diversity may be important for regional biodiversity conservation as well as biological control of vineyard pests. 2. We surveyed ground-dwelling spiders in habitats at different management intensities (natural habitat remnants, organic vineyards, and conventional vineyards) in the vineyard landscape of the Cape Floristic Region (CFR) biodiversity hotspot, South Africa, to examine the effects of local land use on spider diversity. 3. Natural habitat remnants contributed significantly to the overall diversity, and supported rare families and unique species that were not found in the agricultural matrix. Nevertheless, vineyards still supported fairly high spider diversity, with a tendency for higher species richness in organic vineyards. Environmental variables relating to plant diversity, management intensity and distance to nearest natural habitat influenced spider abundance and species richness, and changes to these factors may improve the habitability of the vineyard landscape for spiders. 4. All habitats supported various spider families that are known to prey on South African crop pests. In addition, spiders were abundant in both sampling seasons (autumn and spring), but showed a significant increase in vineyards early in the growing season, suggesting that they may provide early-season background regulation of pests. 5. There is considerable opportunity for spider conservation in the CFR vineyard landscape, as well as the possibility of associated benefits to biological control within vineyards. [ABSTRACT FROM AUTHOR]

Humanity relies on soil fauna for important ecosystem services, as such our soils need sustainable management to ensure long-term biotic viability. However, environmental factors influencing the distribution and diversity of soil fauna are poorly understood, which limits effective conservation management. To address this issue, we assessed the influence of variables at different spatial scales (site, soil, and landscape) in different biotopes (natural forest patches and grasslands) in two contrasting geographical regions (inland Midlands and coastal Zululand, South Africa) on ant and springtail diversity in large-scale conservation corridors among commercial plantations. Midlands sites, with complex topography and nutrient-rich and deep soils, had higher soil arthropod diversity than sandy, shallow Zululand soils. Indigenous forest and grassland supported complementary arthropod assemblages. The responses of arthropod diversity and assemblage composition to local environmental variables varied greatly among biotopes, taxa, and regions, but responses were more pronounced in the Midlands than in Zululand, and arthropods were more responsive to site- and soil-related variables than to landscape variables. Lower soil biodiversity in Zululand compared to the Midlands emphasizes that management efforts to limit further homogenization from inappropriate management is particularly important in this sandy region. Lack of common drivers of soil arthropod diversity suggests that conservation strategies need to be tailored to different locations. Nonetheless, the conservation of both indigenous forest and grassland, together with promotion of small-scale spatial heterogeneity, will maximally benefit the widest range of soil-inhabiting organisms. • Environmental drivers of soil fauna distributions are poorly understood. • Soil arthropod response is taxon, biotope and region specific. • Small-scale variables are more influential than landscape-scale variables. • Remnant natural areas contribute to regional soil biodiversity. [ABSTRACT FROM AUTHOR]

The California floristic province is home to several threatened or endangered species and has been the focus of numerous conservation efforts. These conservation efforts have largely ignored the diverse and distinctive arthropod fauna found in this region., We investigate the species boundaries of the four tarantula (Araneae: Theraphosidae) species endemic to California's Southern Coast Ranges through molecular phylogenetic analysis using a 680 bp region of the mitochondrial gene cytochrome oxidase subunit 1 from 51 individuals., Our analysis resulted in a well-supported phylogeny showing three distinct clades. As a result, we recognise only one species in the Southern Coast Ranges ( Aphonopelma brunnius, with A. chamberlini and A. smithi treated as junior synonyms; if the holotype of A. rileyi is located it will likely be a synonym as well). Two additional species were found in the foothills of the Sierra Nevada., Although the tarantulas in California's Southern Coast Ranges are not as endemic as was previously thought, their position as top arthropod predators make them ideal sentinel species, suggesting they should be targeted by conservationists. Furthermore, our analyses illustrate the importance in using molecular tools to investigate biodiversity. [ABSTRACT FROM AUTHOR]

The Cape Floristic Region (CFR), South Africa, is a biodiversity hotspot challenged by intensive wine production. Innovative approaches are being explored to optimize wine production without compromising biodiversity. As organic farming enhances biodiversity conservation in many other regions, the aim here was to assess the potential of organic vineyard management for conserving CFR soil surface arthropod diversity. Pitfall traps were used to sample arthropods in three study areas, each of which included an organic vineyard, an integrated vineyard and a natural vegetation reference habitat. Overall arthropod morphospecies richness was highest in natural sites, followed by organic vineyards and then integrated vineyards. The same trend was seen for predators, saprophages and phytophages. The ability of organic vineyards to sustain more morphospecies than integrated vineyards were partially due to higher non-crop vegetation complexity and less intense management in the organic vineyards. Arthropod assemblages were similar in organic and integrated vineyards, while both land-uses differed greatly from natural sites. Variation among natural vegetation assemblages in different study areas was also much greater than among assemblages of cultivated sites. Organic vineyard management has the potential to make an important contribution to arthropod conservation in the CFR at the field scale. However, at the landscape scale, natural habitat supports a much wider variety of morphospecies, and the preservation of natural fragments in the vineyard landscape may be the most effective measure to increase biodiversity in the winelands. [ABSTRACT FROM AUTHOR]

Abstract: Infection by endosymbiotic bacteria is an underappreciated threat to endangered arthropods with serious implications for captive management programs. We examined the nature of Wolbachia infection in the North American endangered Karner blue butterfly, Lycaeides melissa samuelis, as a case study. Screening for Wolbachia across the range of the species confirmed widespread infection in the western half of the Karner blue’s range. Multilocus sequence typing using six genes confirmed that the infection in the western populations is attributable to a single strain of Wolbachia. This strain was also detected in the closely related Melissa blue butterfly, L. m. melissa, the presumed source of the infection. The infection in the Karner blue butterfly was perfectly correlated with the presence of a foreign mitochondrial DNA variant present in the Melissa blue butterfly, consistent with the hypothesis that the mitochondrial introgression was driven by the spread of Wolbachia. A single individual out of 71 screened from the eastern portion of the range of the Karner blue butterfly was also infected, however this infection was attributable to a different strain. Simulation models of the demographic effects of the spread of Wolbachia infection to uninfected populations and metapopulations suggest that such an infection might further reduce already small population sizes and substantially increase the probability of population extirpation. We discuss threats to other endangered arthropods in the light of this case study and make recommendations for minimizing the impact of endosymbiont infections in conservation plans, especially those including captive propagation and augmentation of endangered arthropod populations. [Copyright &y& Elsevier]

Regions of mediterranean-type climate represent most extra-tropical biodiversity hotspots, being both highly diverse and highly endangered. Though renowned for their plant richness, these regions' insects constitute the bulk of their alpha diversities. Data on insect distribution and rarity are generally lacking for such regions, and are often considered unattainable. Intensive field inventories combined with statistical extrapolation methods can provide a sufficient understanding of alpha, beta, and gamma diversity components for application to conservation planning. These are essential to assessing the adequacy of a regional reserve network for the conservation of insect diversity. Here the beetle faunas of three protected areas spanning three major ecoregions in the California Floristic Province were inventoried and analyzed for species richness, complementarity, and uniqueness. These surveys produced collectively nearly 1,200 species from all three sites, estimated to be about 80% of their total faunas. Diversity was highly partitioned among sites, no one site containing more than 60% of the species. Dissimilarity was moderate to high for all comparisons, and all sites contained >40% unique species. Comparison of these results with those based on species of co-occurring plants reveal incongruent species richness but congruent similarities among sites. These results provide quantitative support to the perception that mediterranean insect faunas show high spatial variability. Along with online specimen level data on distribution, rarity, and seasonality, these results will help speed the incorporation of insect data into serious conservation planning. [ABSTRACT FROM AUTHOR]

Although hyperdiverse groups like terrestrial arthropods are almost certainly severely impacted by habitat fragmentation and destruction, few studies have formally documented such effects. In this paper, we summarize the results of a multifaceted research approach to assess the magnitude and importance of anthropogenic population extinction on the narrowly endemic trapdoor spider genus Apomastus. We used geographical information systems modeling to reconstruct the likely historical distribution of Apomastus, and used molecular phylogeographic data to discern population genetic structure and detect genetic signatures of population extinction. In combination, these complementary lines of inference support direct observations of population extinction, and lead us to conclude that population extinction via urbanization has played an important role in defining the modern-day distribution of Apomastus species. This population loss implies coincident loss of genetic and adaptive diversity within this genus, and more generally, suggests a loss of ground-dwelling arthropod population diversity throughout the Los Angeles Basin. Strategies for minimizing this loss are proposed. [ABSTRACT FROM AUTHOR]

Abstract: Like most ecosystems of the world, tropical dry forests of the central coast of the Gulf of Mexico are inadequately preserved. Given that reserve expansion is unlikely, it is imperative that the conservation capacity of the matrix surrounding reserves is enhanced. Here, we examine the habitat value of isolated pasture trees and patches of secondary regrowth in terms of their terrestrial and arboreal ant assemblages in both a wet and dry season. These simplified wooded systems increase species densities within the agricultural matrix and provide habitat for some forest ant species. Estimated species richness of arboreal ants was particularly low on isolated trees, highlighting an important limitation. This was not the case for terrestrial ants, which were particularly species rich under isolated trees. We also found that the inter-site variations in species densities and similarity to the forest ant assemblage for terrestrial and arboreal strata were not correlated, suggesting that responses to restoration may not be as uniform as often thought. This has important implications for the use of indicator taxa in suggesting the response of other taxa. In terms of species composition, neither secondary regrowth nor isolated trees were appropriate replacements for forest fragments, even though the studied forest fragments were small (13–32ha). The ant assemblages did not exhibit a seasonal change in composition. However, season influenced the contrast between habitats, with isolated trees being more distinct from pasture, and regrowth more closely resembling forests, during the wet season. Microclimatic variables indicate that the forests were least affected by the tropical dry season, and this may contribute to their characteristic fauna. We conclude that even small forest patches make a unique contribution to landscape conservation and that, where reserves are limited, conscientious management of the landscape matrix may provide some species with sufficient new habitat to survive outside of reserve systems. These conclusions are influenced by both season and strata studied. [Copyright &y& Elsevier]

The article presents a study that examines within-fragment influences in conjunction with landscape-scale responses of representative insect communities from four feeding guilds, including generalists, specialists, multiple life stage habitat use, and predators. Fragment-specific attributes capable of influencing insect diversity include plant species composition, plant biomass, abundance of blooming flowers, and vertical habitat heterogeneity created by the vegetation.

• Diverse herbaceous cover crops promoted vineyard arthropod diversity. • It favoured all taxa, feeding guilds and organisms in different microhabitats. • No effect was detected for agrochemicals used in a sensitive integrated approach. • Individual management practices influenced arthropods more than overall farm regime. Agricultural intensification threatens biodiversity, requiring a shift to agroecological farming. Identifying locally-specific management practices that can effectively enhance biodiversity can help guide farmland conservation efforts. We assess the effect of management practices and environmental variables on arthropod diversity under varying vineyard management regimes in a South African biosphere reserve. We also determine whether the implementation of these practices and their combined effect on arthropods differ between integrated and organic vineyards. Arthropod morphospecies richness and evenness were assessed for different taxonomic groups (spiders, beetles, and true bugs), in different positions in the crop (ground level, on cover crops, and on vine foliage) and for different feeding guilds (herbivores, detritivores, and predators). Percentage herbaceous vegetation cover had a consistent positive effect on morphospecies richness across taxa, microhabitats, and guilds. Other vegetation-related variables, such as volume of plant litter, plant species richness, and plant height positively influenced several of the biodiversity responses. We did not detect any negative effect of agrochemicals used in an integrated approach, or a strong effect of overall farming approach (organic vs. integrated) on the species richness or evenness of any of the focal taxa, sampled positions, or guilds. These results indicate that the maintenance of dense and diverse cover crops is a strategic way to enhance vineyard arthropod diversity where other management practices are already implemented sensitively. This highlights that minimal adjustment of management practices can greatly benefit farmland biodiversity conservation and is in keeping with the ethos of the concept of a biosphere reserve. [ABSTRACT FROM AUTHOR]