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Resource subsides can link aquatic and terrestrial ecosystems. Animals that emerge from aquatic ecosystems can transport nutrients that are scarce in terrestrial environments, like long-chain polyunsaturated fatty acids (LC-PUFA), which are synthesized by algae in aquatic environments. LC-PUFAs have critical roles in animal physiology and are precursors to eicosanoids, which help mediate immune responses. We previously found that wolf spiders in wetland ecosystems had higher levels of LC-PUFA and stronger immune responses than nearby upland spiders. However, we could not determine if the stronger immune responses were because of eicosanoids derived from LC-PUFA subsidies or because they had a larger resource pool from aquatic prey subsidies. Here, we use 2 immune assays, 1 affected by eicosanoids and 1 not affected, to differentiate between those 2 possibilities. We fit generalized linear mixed models and found that LC-PUFA subsidies are responsible for the stronger immune responses in wetland spiders. We also found evidence that wolf spiders maintain some immune responses across reproductive states and increase other immune responses when they are gravid. Our results demonstrate that LC-PUFA subsidies can alter immune function in recipient consumers because LC-PUFAs are preferentially stored rather than used as energy. This alteration of immune function could have consequences for disease transmission and pathogen abundance in linked aquatic and terrestrial ecosystems. [ABSTRACT FROM AUTHOR]

Jumping spiders (Salticidae) are a diverse group of non‐web‐building predators and the most species‐rich spider family. The Salticidae Tribe Nannenini consists of a small group of Oriental jumping spiders that are very poorly known. The use of explicit phylogenetic analyses to establish its affinities has so far remained limited. The Nannenini genus Epidelaxia has a peculiar morphology, making its systematic position uncertain. In this study, we present a comprehensive dataset combining molecular and morphological data for Nannenini, including exemplars from all genera. This dataset comprises DNA sequences of approximately 2400 bp, including nuclear genes (18S, 28S and H3) and the mitochondrial gene CO1, sequenced for 40 taxa (20 ingroups and 20 outgroups), along with 61 morphological characters. Notably, both DNA sequences and morphological traits were analysed separately and concurrently for the first time. The Nannenini clade is recovered with high support. Further, Epidelaxia is monophyletic and sister to Tubalaxia gen. n. This is the first hypothesis on the internal phylogenetic structure of Epidelaxia and its placement within the Tribe Nannenini. A new genus Tubalaxia gen. n. and the following new species are described: E. bharathi sp. n., E. somasundaram sp. n., T. castanea sp. n., T. aurea sp. n. The following new combination is proposed: Tubalaxia minuta (Prószyński, 1992) comb. n. Epidelaxia albostellata, E. albocruciata and E. obscura are redescribed. It is worth noting that the newly described species face endangerment due to their limited distribution and small population sizes. [ABSTRACT FROM AUTHOR]

The ideal free distribution (IFD) theory predicts that individuals are free to move among habitat patches and distribute among them “ideally,” in order to maximize individual evolutionary fitness. Size and quality of habitat patches then should directly impact the number of individuals occupying them, and connectivity of habitat patches likely plays a role if dispersal is limited. However, habitat patches can be distributed so that movement no longer can be considered free, for example, when patches are isolated. Challenges stemming from patch delimitation and detection rate of occupants further complicate efforts attempting to resolve such patterns. Here, we utilize as habitat patches the orb webs of four different populations belonging to three golden orb weaver spider species, Nephila pilipes (Fabricius, 1793), Nephilingis livida (Vinson, 1863), and Trichonephila clavipes (Linnaeus, 1767), and the obligate spider kleptoparasites (Argyrodinae, Theridiidae) that are associated with their webs. We examine how the IFD predicts the abundance of kleptoparasites under different patterns of patch size and distribution. We found that larger host webs, that is, habitat patches that contain more resources, are occupied by a higher number of kleptoparasitic spiders, regardless of their degree of isolation. Although the free movement prediction is often violated in natural systems, we find no evidence for habitat patch connectivity affecting the abundance of kleptoparasites, indicating that their dispersal ability facilitates the location and colonization of habitat patches regardless of their isolation. Therefore, our results support the interaction between argyrodine kleptoparasitic spiders and the webs of golden orb weavers to be a suitable natural system for studying the IFD. [ABSTRACT FROM AUTHOR]

Anti‐cancer peptides (ACPs) represent a promising potential for cancer treatment, although their mechanisms need to be further elucidated to improve their application in cancer therapy. Lycosin‐I, a linear amphipathic peptide isolated from the venom of Lycosa singorensis, shows significant anticancer potential. Herein, it is found that Lycosin‐I, which can self‐assemble into a nanosphere structure, has a multimodal mechanism of action involving lipid binding for the selective and effective treatment of leukemia. Mechanistically, Lycosin‐I selectively binds to the K562 cell membrane, likely due to its preferential interaction with negatively charged phosphatidylserine, and rapidly triggers membrane lysis, particularly at high concentrations. In addition, Lycosin‐I induces apoptosis, cell cycle arrest in the G1 phase and ferroptosis in K562 cells by suppressing the PI3K‐AKT‐mTOR signaling pathway and activating cell autophagy at low concentrations. Furthermore, intraperitoneal injection of Lycosin‐I inhibits tumor growth of K562 cells in a nude mouse xenograft model without causing side effects. Collectively, the multimodal effect of Lycosin‐I can provide new insights into the mechanism of ACPs, and Lycosin‐I, which is characterized by high potency and specificity, can be a promising lead for the development of anti‐leukemia drugs. [ABSTRACT FROM AUTHOR]

Himalayan orogeny and consequent climatic changes, such as the strengthening of the Asian monsoon, are considered as two main drivers in shaping local biogeography. The mountainous Sinopoda spiders, which are widely distributed in East Asia and Southeast Asia and especially abundant in the mountains near the Himalayas, represent an ideal model lineage for investigating Himalayan biogeography. This is due to their high diversity, limited dispersal ability, and wide elevational distribution, ranging from sea level up to 3500 meters. We investigated the evolutionary history of Sinopoda spiders, focusing on ecological, molecular, and morphological traits in relation to local geological events and fluctuations in Neogene (23.0–2.6 Ma) Asian monsoon patterns. Distribution modeling results show that extant Sinopoda spiders are sensitive to humidity fluctuations. They are mainly distributed in two distinct habitats: areas with moderate precipitation at high altitude (relatively cold) and areas with high precipitation at low altitude (relatively warm). The biogeographical and elevation reconstruction analyses show that as the Himalayas rose and the Asian monsoon intensified, Sinopoda spiders (Sparassidae: Heteropodinae) moved out of the Himalayas (ca 18.1 Ma) then ‘down' the rising mountain slopes (ca 9.6 Ma). We then see a secondary return to the mountains (ca 3.3 Ma) as the severity of the East Asian monsoon decreased. We hypothesize that our ‘out of Himalaya' dispersal pattern hypothesis will also apply to closely related spider groups with limited ballooning ability (e.g. Lycosidae, Thomisidae) or other organisms with low vagility (such as herpetofauna) that are sensitive to humidity and possess similar geographical distributions. [ABSTRACT FROM AUTHOR]

Due to widespread atmospheric deposition of mercury (Hg), all aquatic food webs are contaminated with toxic methyl mercury (MeHg). At high concentrations, MeHg poses a health hazard to wildlife and humans. Spiders feeding in riparian habitats (hereafter referred to as riparian spiders) have been proposed as sentinels of MeHg contamination of aquatic systems. Riparian spiders are exposed to MeHg through their diets, and the concentration of MeHg in spiders is positively related to the proportion of MeHg‐contaminated emergent aquatic insects in their diets. The use of spiders as sentinels is complex because their MeHg concentrations can vary, not only among ecosystems but also between different spider taxa and as a function of spider body size. The objective of the present study was to examine how the level of ecosystem contamination, spider taxon, and spider body size interact to influence MeHg concentrations in four genera of riparian spiders from two rivers with different levels of Hg contamination. We collected four genera of riparian spiders (Tetragnatha sp., Larinioides sp., Pardosa sp., and Rabidosa sp.) from two sites along both the Clear Fork of the Trinity River and the West Fork of the Trinity River (Fort Worth, TX, USA). We analyzed concentrations of MeHg in different body sizes of spiders from each genus. We found that MeHg contamination of the river ecosystem, spider taxon, and spider body size were important determinants of MeHg concentration in riparian spiders. The results suggest that any of the four taxa of riparian spiders from the present study could be used as sentinels of aquatic MeHg contamination, but they should not be used interchangeably because of the interdependence between the effects of ecosystem contamination level, spider taxon, and body size. Future studies utilizing riparian spiders as sentinels of biomagnifying aquatic contaminants (e.g., MeHg, polychlorinated biphenyls) should consider the potentially complex interaction effects between ecosystem contamination level, spider taxon, and spider body size. Environ Toxicol Chem 2024;00:1–7. © 2024 The Author(s). Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]

Simple Summary: Spiders play crucial roles in ecosystems as predators, prey, and indicators of environmental health, yet they have not been well-studied. This study compared different methods for surveying spider populations to understand their effectiveness and biases. A new vibration-based method, using an idling diesel tractor to attract spiders, was compared with the traditional methods of pitfall trapping and hand collection of spiders at night. Night collections yielded the highest species richness and diversity compared to the other methods. Pitfall traps were biased towards ground-dwelling species, while night collections targeted spiders in different vegetative strata. The study highlighted the importance of combining survey methods to accurately determine diversity in spider populations and emphasized the need for further research to better understand spider ecology. As the night collection and vibration-based methods were similar in labor required and material costs, we recommended a combination of these methods be used as there were species of spiders captured using the vibration-based method that were not captured in night collections. Further research is needed to refine the vibration-based method to better understand the underlying mechanism of how vibration attracts spiders and to improve the portability of the vibration source. Spiders have important ecological roles as generalist predators, are a significant source of food for many other species, and are bioindicators of environmental health. However, spiders are poorly studied. Given their importance, a comparison of spider survey methods used to determine differences in spider diversity and abundance is required to understand their limitations and biases. A new survey method to attract spiders, based on vibration from an idling diesel tractor, was tested and compared to the traditional methods of pitfall trapping and hand collection of spiders at night. Across the three survey methods, there were, in total, 2294 spiders in 34 families, 138 genera, and 226 species identified. Spider species diversity and richness were significantly greater for spiders collected at night than from the other two methods (spiders collected in pitfall traps and attracted to vibration). The collection of spiders using the night collection and vibration-based methods were very similar in terms of labor required and material costs. Of all spider species identified, 80% were captured during hand collection, 30% through pitfall trapping, and 30% from vibration-based collection. Most species of spiders caught in pitfall traps were species known to be primarily ground-dwelling, whereas both arboreal and ground-dwelling spiders were collected at night and as a result of being attracted and collected using the vibration-based method. [ABSTRACT FROM AUTHOR]

All animal species, from arthropods to vertebrates, must deal with occasional stressors in their lives, though most research on this has been focused on vertebrates. Meanwhile, our understanding of stress reactions in arthropod species like spiders is nascent. In the United States, a non‐native orb‐weaving spider, Trichonephila clavata (‘jorō’ spider), is spreading as is its already‐established cousin in the United States, T. clavipes (golden silk spider). Prior study has revealed how these two species have a unique behavioural reaction to physical stressors, whereby they remain in a thanatosis state for a prolonged period compared with other species. Here, we investigate the physiological stress reactions of these Trichonephila spiders by evaluating how each species' dorsal vessel contractions (heart rates) become elevated after being subjected to a non‐lethal stressor. For comparison, we also evaluate two similarly‐sized orb weavers, Argiope aurantia (garden spider) and A. trifasciata (banded garden spider). We record baseline heart rates of inactive, resting, spiders in our lab, then restrain them under an electronic, ‘optocardiographic’, sensor for 10 min, to record their ‘stressed’ heart rates. Argiope aurantia has a pronounced heart rate elevation, for reasons unknown. We observe that all spider heart rates increase during restraint, though each has a species‐specific pattern of elevation over time under restraint. Notably, heart rates of both Trichonephila spiders are less variable under stress, since they tend not to struggle during restraint. Meanwhile, both Argiope spiders frequently struggle, leading to marked fluctuations in cardiac output. The stress reactions of Trichonephila spiders could be characterized as ‘even‐tempered’, which may factor into their ability to live in habitats with frequent disturbances. [ABSTRACT FROM AUTHOR]

Mutualistic and similar ecological associations between tarantulas (Mygalomorphae: Theraphosidae) and other animals are reviewed. Such associations are found to occur in at least nine theraphosid subfamilies. We present 63 new cases of theraphosid–anuran associations from 10 countries, documenting these interactions for the first time in Brazil, Chile, the Dominican Republic, and the Philippines. These findings are the first documentation of such associations for 13 theraphosid and 20 anuran taxa. Additionally, we report, for the first time, associations potentially of mutualistic nature between tarantulas and snakes, whip spiders, and harvestmen. Furthermore, we provide new reports of associations with ants and termites. While some of these interactions appear to be merely tolerated cohabitations, those involving anurans and ants seem to be more prevalent and complex, clearly offering benefits for both organisms. Additionally, based on multiple observations and field experiments, we propose a new hypothesis regarding the evolution of hirsuteness in theraphosids as a defensive strategy against predatory ants. This hypothesis supports previous findings that suggest a similar function for urticating setae incorporated into egg sacs and moulting mats. We further document a unique escape strategy against ants in New World arboreal theraphosids. Finally, the possibility of a chemical defence mechanism through specialised epidermal glands in theraphosids is briefly discussed. [ABSTRACT FROM AUTHOR]

This work aims to describe a new species of Thrixopelma Schmidt, 1994 from southcentral Peru in the Department of Cusco. Thrixopelma choquequirao sp. nov. can be easily distinguished from congeneric species by the low number of labial cuspules, a very long palpal tibia, morphology of the male palpal bulb and female spermathecae. Currently the genus Thrixopelma comprises seven formally described species which inhabit Perú and Ecuador, distributed in Amazonian rainforest, Coastal Dry Forest, and Andean Dry Forest. [ABSTRACT FROM AUTHOR]

Tropical rainforests are one of the most diverse ecosystems worldwide, yet the mechanisms driving the spatial distribution of their biodiversity remain poorly understood. Here, we tested the effects of elevation, sampling method and their interaction on α and β diversities of spider assemblages between two close elevations in one tropical forest of French Guiana. Through a standardized protocol, both ground- and vegetation-dwelling (up to 2.5-m high) assemblages were sampled at medium and high elevations, during day and night using 3 complementary methods (beating, sweeping, and nocturnal hand collecting). Despite a lower total number of species at high elevation, we found no significant effect of elevation on mean species richness. However, elevation had a significant effect on species composition, notably with less web builders and more ground hunters at higher elevations. In addition, we found a significant effect of sampling methods on both estimated species richness and composition. These results suggest that even slight elevation shape spider assemblages of tropical forests, which probably contributes to the high turn-over and amazing gamma diversity of these ecosystems. [ABSTRACT FROM AUTHOR]

Agroecosystem simplification for greater food production has led to the loss of ecosystem services such as pest control by predators. Plant diversification has shown excellent potential to improve the diversity of crop predators such as spiders.However, in agroecosystems with frequent disturbances such as annual crops, it is unknown whether the effect of plant diversification on spiders depends on the surrounding landscape and the stages of the agricultural cycle (i.e., periods with differences in vegetation, weather and agricultural practices).Here, we evaluated the effect and interaction of local management (plant diversification), landscape (forest areas) and agricultural cycle on the richness and abundance from the main spider guilds of a maize polyculture in Mexico.We found that greater crop diversification (i.e., addition of legumes and leafy plants) caused a greater abundance of ground‐hunting spiders. We also show that a larger area of forest around the crop favours a greater richness and abundance of ground‐ and vegetation‐hunting spiders.We found that each stage of the agricultural cycle had a different spider richness and abundance, ground hunters were more common at the beginning of the agricultural cycle, while vegetation hunters and web‐builders were more common during the peak developmental stages of the crops.Our findings support the idea that to foster functionally diverse spider communities that potentially enhance natural pest control, we must jointly manage plant elements within the crop, in the surrounding landscape, considering the high dynamics of spider communities throughout the agricultural cycle. [ABSTRACT FROM AUTHOR]

Temporal change in vegetation complexity and field management may interactively affect the structure of predator–prey networks in agroecosystems and consequently alter the biocontrol potential of predators. There is a limited number of studies that have addressed these questions for generalist predator–prey networks.We investigated how vegetation complexity during crop development and management type (conventional vs. organic) affect the trophic networks of orb‐weaving spiders and their prey in rainfed lowland rice ecosystems in southern Thailand. Specifically, we investigated orb‐weaving spiders and prey composition, prey selectivity and network structure.Overall, orb‐weaving spiders captured mostly detritus‐associated Diptera, aquatic‐associated Ephemeroptera and Hemiptera pests. The increasing vegetation complexity during rice development significantly restructured the network of orb‐weaving spiders and prey, while field management had only a marginal effect. The increased vegetation complexity during rice development led to an increased number of weak trophic interactions in comparison to few but strong interactions in simple vegetation.Our results indicate that increasing the number of spider species per prey taxon (prey vulnerability) in late rice season may enhance their top‐down control of prey including rice pests. This study also highlights that the network complexity and the stability of rice ecosystems increased during the rice growing season as the vegetation became more complex.Future practices could look for a way to support the densities of detritus and aquatic insects and to artificially increase habitat complexity during the early stage of rice development to improve the biocontrol services provided by the orb‐weaving spiders. [ABSTRACT FROM AUTHOR]

Comparable data is essential to understand biodiversity patterns. While assemblage or community inventorying requires comprehensive sampling, monitoring focuses on as few components as possible to detect changes. Quantifying species, their evolutionary history, and the way they interact requires studying changes in taxonomic (TD), phylogenetic (PD) and functional diversity (FD). Here we propose a method for the optimization of sampling protocols for inventorying and monitoring assemblages or communities across these three diversity dimensions taking sampling costs into account. We used Iberian spiders and Amazonian bats as two case-studies. The optimal combination of methods for inventorying and monitoring required optimizing the accumulation curve of α-diversity and minimizing the difference between sampled and estimated β-diversity (bias), respectively. For Iberian spiders, the optimal combination for TD, PD and FD allowed sampling at least 50% of estimated diversity with 24 person-hours of fieldwork. The optimal combination of six person-hours allowed reaching a bias below 8% for all dimensions. For Amazonian bats, surveying all the 12 sites with mist-nets and 0 or 1 acoustic recorders was the optimal combination for almost all diversity types, resulting in >89% of the diversity and <10% bias with roughly a third of the cost. Only for phylogenetic α-diversity, the best solution was less clear and involved surveying both with mist nets and acoustic recorders. The widespread use of optimized and standardized sampling protocols and regular repetition in time will radically improve global inventory and monitoring of biodiversity. We strongly advocate for the global adoption of sampling protocols for both inventory and monitoring of taxonomic, phylogenetic and functional diversity. [ABSTRACT FROM AUTHOR]

Predation exerts a profound influence on the evolution of camouflage and detection abilities in both predators and prey. For instance, flower‐visiting spiders need to ensure their concealment when ambushing on flowers, which compels pollinators to check any spider cues cautiously before landing. Although numerous studies have examined the visual camouflage of spiders deceiving bees, little is known regarding whether spiders also employ olfactory camouflage. Additionally, the detection of spiders by dipteran insects is often overlooked, despite them being major non‐bee pollinators. Here, we explored the detection ability of dipteran pollinators and the crypsis skill of spiders from both olfactory and vision perspectives using the housefly Musca domestica L. (Diptera: Muscidae) as prey, the crab spider Ebrechtella tricuspidata (Fabricius) (Araneae: Thomisidae) as predators and chamomile Matricaria recutita L. (Asteraceae) as substrates. Our olfactory experiments revealed that experienced houseflies could respond to and avoid spider odour. However, this response did not appear to be innate, as naive individuals showed no aversion. Moreover, experienced houseflies did not have any avoidance behaviours to the mixed odours of spider and flower, indicating that spiders achieved olfactory crypsis utilizing floral scent. Our vision experiments and visual modelling demonstrated that houseflies could detect spiders positioned on flower. Surprisingly, instead of avoiding them, houseflies exhibited a preference for flowers occupied by female spiders, suggesting the attractive nature of female spider colouration. This paper provides evidence for the first time that crab spiders use floral scent to achieve olfactory crypsis and proposes a potential yellow‐signalling mechanism for crab spiders to attract insects. [ABSTRACT FROM AUTHOR]

Aim Location Taxon Methods Results Main Conclusions Mountains are often used to study how environmental factors influence biodiversity. However, we have limited understanding of the processes causing biodiversity variation in mountains and whether such processes vary across trophic levels and spatial scales. The aim of this study was to evaluate (i) whether community assembly processes varied along elevational gradients, (ii) whether there were differences in such variation between primary producers (vascular plants) and secondary consumers (spiders) and (iii) whether there were scale dependencies in any elevational variation in community assembly.Fennoscandia, Northern Sweden.Vascular plants, spiders.We used phenotypic and phylogenetic dispersion to quantify how elevation influenced community assembly of vascular plants and spiders and whether there were any scale dependencies in such influences. Our original data of plant and spider communities came from our own field surveys, phenotypic dispersion was calculated based on matrices of ecological traits, and phylogenetic dispersion was calculated from phylogenetic trees for each organism group. Trait matrices were based on a combination of literature values and our own measurements. The phylogeny for vascular plants was based on a published plant super‐tree, whereas the phylogeny for spiders was created by ourselves based on the DNA sequences at the mitochondrial cytochrome c oxidase subunit 1 (COI).Plants were environmentally filtered throughout all elevations and scales, but the importance of convergent evolution increased with elevation. For spiders, the importance of environmental filtering as well as niche conservatism increased with elevation. For both groups, communities at smaller scales were more influenced by biotic regulation and niche conservatism than at larger scales.Our study highlights both taxonomic differences and scale dependencies in how elevation influences community assembly. We argue that these results can have broad ramifications for our understanding of how spatial variation in biodiversity is generated and maintained. This may have particular relevance for our ability to predict the ecological consequences of climate change. Our results further highlight that high elevation specialists may suffer increased risks of climate driven extinctions due to a combination of increased competition and increased fragmentation of suitable habitats. Particularly for spiders, which had high elevation specialists clustered along specific lineages, such extinctions could lead to significant loss of phylogenetic variation. [ABSTRACT FROM AUTHOR]

Ants and termites are insect groups that make up most of the insect biomass in tropical ecosystems. Due to their social structure and abundance, they are some of the most bountiful prey available to other invertebrates such as spiders. However, ants and termites possess dangerous defense strategies, thus limiting their accessibility to general predators. Here, we report on an unexpected finding of a three-way predator-prey-kleptoparasite interaction in Madagascar among a termite Nasutitermes sp. (prey), a previously unknown theridiid spider Vigdisia praesidens gen. nov., sp. nov. (predator), and an ant Pheidole spinosa (kleptoparasite). Our field observations suggest that the spiders are able to detect a damaged termite nest from a distance to disperse onto it and prey on its residents. Kleptoparasitic ants also arrive on the scene to steal from the spiders their termite prey. Both the spider and the ant seem to possess some degree of behavioural prey specialisation for Nasutitermes termites. The here described ecological interaction warrants further study to better understand the exploitation of signals by such phylogenetically diverse arthropods. [ABSTRACT FROM AUTHOR]

ABSTRACT Venom represents a key adaptation of many venomous predators, allowing them to immobilise prey quickly through chemical rather than physical warfare. Evolutionary arms races between prey and a predator are believed to be the main factor influencing the potency and composition of predatory venoms. Predators with narrowly restricted diets are expected to evolve specifically potent venom towards their focal prey, with lower efficacy on alternative prey. Here, we evaluate hypotheses on the evolution of prey‐specific venom, focusing on the effect of restricted diet, prey defences, and prey resistance. Prey specificity as a potential evolutionary dead end is also discussed. We then provide an overview of the current knowledge on venom prey specificity, with emphasis on snakes, cone snails, and spiders. As the current evidence for venom prey specificity is still quite limited, we also overview the best approaches and methods for its investigation and provide a brief summary of potential model groups. Finally, possible applications of prey‐specific toxins are discussed. [ABSTRACT FROM AUTHOR]

Floodplains along rivers and streams are characterised by a high habitat heterogeneity and a large biodiversity. However, floodplains are highly threatened by anthropogenic activities such as channelisation and bank enforcement of watercourses. While floodplains along rivers are well known for their importance for riparian biodiversity, the conservation value of floodplains along small streams is less understood. We studied carabid beetles (Coleoptera: Carabidae) and ground‐dwelling spiders (Arachnida: Aranea) along forested small streams (~ up to 5 m width) in Rhineland‐Palatinate (Germany). We investigated 16 pairs of floodplains (natural stream sites with shallow bank and regular flooding events) and controls (deeply cut stream sites without regular flooding), where we sampled carabid beetles and spiders at different distances to the stream bank (0, 5 and 10 m). We found that floodplains along small streams had contrasting value for carabid beetles and ground‐dwelling spiders. For carabid beetles, we observed several typical floodplain species and distinct species assemblages and 2.7 times more individuals across species of conservation concern in floodplain sites. Moreover, species richness and total number of individuals of carabid beetles were highest directly at the stream bank (0 m distance) of floodplains compared with the more distant locations, while the opposite was found for the control stream sites. The spider composition also differed between floodplains and control steam sites, but only one typical floodplain species was detected. Species richness and number of individuals in ground‐dwelling spiders were lower in floodplains than in control stream sites. We conclude that the conservation value of floodplains of small streams is taxa‐dependent and that they appear less relevant for ground‐dwelling spiders but provide important habitats for riparian carabid beetles. [ABSTRACT FROM AUTHOR]

Intraguild predation occurs when an organism preys on a competitor. This ecological interaction can have considerable consequences on the population dynamics of predators and indirectly affect their prey. In arachnids, it is a quite common phenomenon, but it has been poorly documented in the Neotropical region. Here, we present records of 16 species feeding on other 14 species of arachnids. The most common families that acted as predators were Buthidae (Scorpiones) and Salticidae (Araneae), while the most common prey were members of the families Araneidae and Ctenidae (Araneae). In our survey, Drake Bay, in Costa Rica, is overrepresented due to years of systematic observations by two of the coauthors. [ABSTRACT FROM AUTHOR]

Idealized ring species, with approximately continuous gene flow around a geographic barrier but singular reproductive isolation at a ring terminus, are rare in nature. A broken ring species model preserves the geographic setting and fundamental features of an idealized model but accommodates varying degrees of gene flow restriction over complex landscapes through evolutionary time. Here we examine broken ring species dynamics in Calisoga spiders, which, like the classic ring species Ensatina salamanders, are distributed around the Central Valley of California. Using nuclear and mitogenomic data, we test key predictions of common ancestry, ringlike biogeography, biogeographic timing, population connectivity, and terminal overlap. We show that a ring complex of populations shares a single common ancestor, and from an ancestral area in the Sierra Nevada mountains, two distributional and phylogenomic arms encircle the Central Valley. Isolation by distance occurs along these distributional arms, although gene flow restriction is also evident. Where divergent lineages meet in the South Coast Ranges, we find rare lineage sympatry, without evidence for nuclear gene flow and with clear evidence for morphological and ecological divergence. We discuss general insights provided by broken ring species and how such a model could be explored and extended in other systems and future studies. [ABSTRACT FROM AUTHOR]

Many children around the globe suffer from spider phobia. Virtual reality exposure therapy is an effective phobia treatment, but so far predominantly tailored for adults. A gamified approach utilizing gaze interaction would allow for a more child-friendly and engaging experience, and provide the possibility to foster working mechanisms of exposure therapy. We developed an application in which children make spiders change in positively connoted ways (e.g., make them dance or shrink) if sufficient visual attention towards them is captured via eye tracking. Thereby, motivation for and positive affects during exposure towards spiders are aspired. In this pilot study on 21 children without (n = 11) and with fear of spiders (n = 10), we examined positive and negative affect during exposure to a virtual spider and to different gaze-related transformations of the spider within a quasi-experimental design. Within a one-group design, we additionally examined fear of spiders in spider fearful children before and one week after the intervention. We found that significantly more positive than negative affect was induced by the spiders' transformations in children without and with fear of spiders. Fear of spiders was furthermore significantly reduced in spider-fearful children, showing large effect sizes (d >.80). Findings indicate eligibility for future clinical use and evaluation in children with spider phobia. [ABSTRACT FROM AUTHOR]

There are various modern pest-control management systems used in the current apple production, such as integrated pest management (IPM) or organic systems. All aims to support occurrence of natural enemies that should help to reduce populations of pests. Here we investigated the effect of fungicide-treated and fungicide-free (resistant tree varieties) treatment combined with biological, IPM, and conventional systems on spiders, as the major group of natural enemies occurring on foliage of apple trees. The biological treatment was based on the use of biopesticides; IPM system was based on the use of selective insecticides, conventional included the use of broad-spectrum insecticides. Abandoned plot served as a control. The study was done for three consecutive years. Spiders were sampled from canopies by beating at weekly intervals during season. We found that fungicide-treated plots had lower abundance of spiders for two years but not species richness than fungicide-free plots. Among the three pest-control management systems, IPM and conventional supported greater spider abundance but not species richness than the biological treatment. Comparison of spider abundance before and after insecticide applications revealed that only very few pesticides, particularly the broad-spectrum ones, reduced spider numbers. In addition, we focused on the comparison of three traits (body size, maturity, fecundity) among treatments. Of six species, only Philodromus cespitum showed a smaller body size on biological than the other treatments. There were three species in which adults occurred earlier on conventional treatment than on the other treatments. Neither clutch size of Phylloneta impressa nor egg size was different among treatments. The small though significant differences in abundance, richness, and selected traits, found among IPM, conventional, and biological treatments and the control show that these pest-control management systems had similar effect on spiders. Use of IPM system combined with scab resistant apple varieties is recommended. [ABSTRACT FROM AUTHOR]

We present new records and species of running crab spiders (family Philodromidae) from Colombia representing four genera: Apollophanes O. Pickard-Cambridge, 1898, GephyrellulaStrand, 1932, PetrichusSimon, 1886, and Tibelloides Mello-Leitão, 1939. The genus Gephyrellula is recorded based on the newly described G. lavidabonitasp. nov., known from females from the department of Magdalena, constituting the northernmost known locality for the genus, at Sierra Nevada de Santa Marta. This new species can be differentiated from the (previously monotypic) type species G. violacea (Mello-Leitão, 1918), known from southeastern region of Brazil, by the longer than wide epiginal plates (wider than long in G. violacea), with narrower and shorter ducts of the glandular heads (thicker and longer in G. violacea), and by their more posteriorly placed fertilization ducts. The genus Apollophanes is here firstly recorded from males and females of A. punctipes (O. Pickard-Cambridge, 1891) from the Atlántico, Magdalena, Cesar, Cundinamarca, and Boyacá departments. Tibelloides is recorded from males and females of T. bryantae (Gertsch, 1933), from the departments of Magdalena and Meta, also representing northernmost known localities for the genus. Finally, new faunistic and taxonomic data is presented for Petrichus. Our examination of the holotype of Thanatus granadensisKeyserling, 1880 demonstrates this species is conspecific with more recently collected and better-preserved specimens of Petrichus griseusBerland, 1913, from the department of Santander. Therefore, we propose the new combination Petrichus granadensiscomb. nov., regard P. griseus as its junior synonym syn. nov., and update knowledge of its distribution. [ABSTRACT FROM AUTHOR]

A new species of the genus HibanaBrescovit, 1991, previously known only from the Americas, is described from Ascension Island, based on both sexes: Hibana ascensionensissp. nov. complemented with colour photographs of specimen habitus, male chelicera, and the copulatory organs of both sexes. Hitherto, the family Anyphaenidae Bertkau, 1878 had not been recorded from Ascension Island, nor any other mid-Atlantic island. The new species is related to, but distinct from, H. tenuis (L. Koch, 1866) and H. talminaBrescovit, 1991. The unusual indentation of male chelicerae in Hibana is documented and figured in detail for the first time. [ABSTRACT FROM AUTHOR]

Inbreeding avoidance via polyandry is a common response to combat inbreeding depression across multiple taxa, but has never been investigated in the Halonoproctidae. With a member of this family, the trapdoor spider Bothriocyrtum californicum (O. Pickard-Cambridge, 1874), Ramirez et al. (2013) found no evidence for inbreeding in several southern California populations, but did not examine polyandry. Hence, in this study, we determined the extent of multiple paternity in broods of B. californicum. To do so, we gathered broods and mothers from two sites in Los Angeles, CA, and then genotyped each mother and up to 50 spiderlings for variation at the phosphoglucomutase locus. Among nine sets of broods, six showed significant deviations from the Mendelian genotype ratios expected under the hypothesis of single paternity. This indicates that B. californicum females sometimes mate with multiple male partners. This is certainly an adaptive feature for a low-dispersal trapdoor spider residing in island-like units where inbreeding may be more likely. [ABSTRACT FROM AUTHOR]

The unknown male of Echemus escaleraiSimon, 1909 from Morocco is described for the first time, and the epigyne and vulva are illustrated for the first time. The position of the species in the genus EchemusSimon, 1878 is discussed. Cryptodrassus helvolus (O. Pickard-Cambridge, 1872), previously known from Cyprus, Russia (Northern Ciscaspia), and Israel, is reported for the first time in Morocco, Algeria, and Tunisia. [ABSTRACT FROM AUTHOR]

Prosoponoides shaanxisp. n. is described, based on a single male from high altitude in the Qinling Mountains, Shaanxi Province, China. The species is similar to both Oriental Prosoponoides hamatumMillidge & Russell-Smith, 1992 and P. sinense (Chen, 1991), but it can easily be distinguished by structural details of the palp. Prosoponoides shaanxisp. n. is the first species of the genus reported from the Palaearctic Region. [ABSTRACT FROM AUTHOR]

A survey of 21 species of Salticidae newly collected from the Bidoup–Nui Ba National Park (Da Lat Plateau, south-eastern Vietnam) is presented. Eleven species are described as new: Bindax dalatsp. n. (♀), Eupoa parvasp. n. (♂♀), Hasarius dalatensissp. n. (♂♀), Indopadilla abramovisp. n. (♂), Maileus obscurussp. n. (♀), Orcevia bidoupsp. n. (♂♀), Pancorius inexpectatussp. n. (♂♀), Phintelloides rarussp. n. (♂), Synagelides nuibasp. n. (♂♀), Thiania subtilissp. n. (♂♀), and Toxeus pseudohainansp. n. (♂). Three species—Irura pengiGuo, Zhang & Zhu, 2011, Ptocasius paraweyersiCao & Li, 2016 and Toxeus hainan Wang & Li, 2022—are recorded from Vietnam for the first time. Three new synonyms are established: Plexippus pocockii Thorell, 1895 syn. n. and Burmattus sinicus Prószyński, 1992 syn. n. with Plexippus albo-punctatus Thorell, 1895; and Pellenes gerensisHu, 2001syn. n. with Burmattus nitidus (Hu, 2001). [ABSTRACT FROM AUTHOR]

A new Brazilian genus of curtain-web spiders, family Dipluridae Simon, 1889, Harpathelegen. nov., is described, with Harpathele gymnognathacomb. nov. (Bertkau, 1880) (Rio de Janeiro state) as its type species. The new genus is a lyrate Diplurinae and it is known only from southeast Brazil. It may be recognized by the relatively small body, maxilla with dorsal transverse suture showing distinct curve at its basal third, a field of numerous long and thin setae above that suture, and a field of small rigid bristles below it, among other characters. Harpathele gymnognathacomb. nov. (Bertkau, 1880) is revalidated and redescribed, with the designation of a neotype and the first description of a male, based on specimens collected in its type locality that match the original description and illustrations, and is pointed as senior synonym of Diplura annectens (Bertkau, 1880). Additionally, two species of the new genus are described: Harpathele cariacicasp. nov., based on females from Espírito Santo state, and Harpathele salinassp. nov., based on males from Rio de Janeiro state. [ABSTRACT FROM AUTHOR]

A new dictynid species of the genus ThallumetusSimon, 1893 with a highly modified male palpal patella and tibia, combined with a unique shape to the epigyne, is described from Ascension Island in the South Atlantic Ocean: Thallumetus ascensionensissp. nov. The new species represents the first report of of the family Dictynidae from Ascension and also the first Old World record of Thallumetus. The northernmost and southernmost limits of the family are briefly discussed. [ABSTRACT FROM AUTHOR]

Two new species of ZodariellumAndreeva & Tyshchenko, 1968 (Araneae: Zodariidae) are described on the basis of male holotypes collected in Central Asia: Z. doroshkinisp. n. from Gorno-Badakhshan in eastern Tajikistan, and Z. kattakumsp. n. from Surxondaryo in southeastern Uzbekistan. Additionally, Z. turanicum Zamani & Marusik, 2022 is recorded from Uzbekistan for the first time, and new distribution records are provided for Z. bactrianum (Kroneberg, 1875) and Z. mongolicumMarusik & Koponen, 2001. Detailed descriptions, figures, diagnoses, distribution maps and photographs of habitats of the studied species are provided. [ABSTRACT FROM AUTHOR]

In the past decade, environmental DNA (eDNA) assays have become an essential tool to investigate species presence with samples from the environment instead of collected specimens. eDNA sampling techniques have proved their worth in freshwater and marine studies; now, some trends emerge for their use in terrestrial habitats and particularly to study arthropods. After a systematic review of the literature, we illustrate and analyse the diversity of such studies and discuss their benefits and drawbacks.We identified the most relevant research themes and focused on (i) the taxa and environmental sample types targeted and (ii) the details of the survey scheme. In parallel, we also assessed the available number of sequences from cytochrome c oxidase subunit I (COI), 16S and 18S barcode regions for four major taxa (spiders, centipedes, springtails and insects) in relation to their diversity.We found strong taxonomic and geographic biases regarding coverage per barcode. eDNA research on terrestrial arthropods mainly focuses on insect species that affect humanity in a positive or negative way, and the availability of sequences is much higher for species from temperate‐developed countries than from tropical ones. Moreover, although a high variety of environmental samples are being used, most studies do not assess the barcode completeness of the target taxa nor compare the efficacy of eDNA monitoring technique to other well established and known traditional techniques.Careful workflow designs and comparisons are needed before giving any management or conservation advice as eDNA monitoring does not come without error. Strengths and weaknesses of eDNA assays for conservation are discussed. [ABSTRACT FROM AUTHOR]

In this paper, we provide additional data on the orb-weaver spider fauna (Araneae: Araneidae) of Kosovo. Three species are reported for the first time from this country: Araneus grossus (C.L. Koch, 1844), Argiope lobata (Pallas, 1772) and Cyclosa oculata (Walckenaer, 1802). In consideration of the findings and the updated checklist of Araneidae in this study, the documented number of spider species in Kosovo has now increased to 251. Given that the spider fauna of Kosovo is still not fully explored, our study emphasizes the necessity of ongoing exploration to better comprehend the diversity of spider species within the region. [ABSTRACT FROM AUTHOR]

Symbiotic relationships shape ecological communities and often involve more than two species. Yet few experimental studies examine the impact of symbioses involving three species, particularly any mediating role of third parties, and none involving symbioses of predators.We investigated experimentally the synergistic and antagonistic fitness effects of three symbiotic spider predators across a broad latitudinal range and involving different species combinations.The three‐dimensional web complex of Cyrtophora spiders is a habitat patch to different associates—species of Argyrodes and web‐building Leucauge spider guests. Our field experiments, which manipulated the presence of each guest species and determined the subsequent host weight change, revealed a remarkable consistency in fitness outcomes across the three populations, with the consequences of the interactions between two species depending upon the services provided by a third.Cyrtophora hosts intercepted more prey when web‐building Leucauge guests were present and thus gained more weight. In contrast, Argyrodes guests exerted a fitness cost on their Cyrtophora host, but only when Leucauge guests were absent. A comparison of the prey consumed by Cyrtophora hosts and Argyrodes guests revealed that their diets (reflected in the size of prey) overlapped less in the presence of Leucauge web‐building guests.Our novel experimental study highlights the importance of exploring synergistic effects in multi‐species symbioses. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Urban ecosystems exhibit altered environmental conditions compared to the rural surroundings, including higher temperatures, the so‐called urban heat island (UHI) effect. Along urbanisation gradients, temperature variations occur at various scales ranging from the landscape to the microhabitat, with possible consequences on living organisms. As ectothermic animals, arthropods are particularly affected by UHIs because warming may directly induce physiological effects on their metabolism.Body size is a commonly used metric to investigate arthropod responses to thermal stress, but the scale‐dependent role of temperature variation as predictor of body size remains unclear. To assess temperature–size relationships across spatial scales and test if a common pattern to several species emerges, we performed morphological measurements on 2283 individuals representing 11 spider species belonging to Hahniidae, Linyphiidae, Lycosidae and Tetragnathidae. Spiders were collected on 36 grasslands distributed along a broad UHI gradient.Intraspecific shifts in body size were related to temperature in the Lycosids Pardosa prativaga and Pardosa pullata at the landscape and local scales, respectively, whereas no clear effects were observed regarding the other examined species. In both species, sex was an important endogenous factor that modulated individual responses; females were more affected than males by temperature.The contrasting amplitudes of the responses observed among Lycodids and the other species indicate that large, low dispersive and univoltine species are under a stronger influence of temperature than small bivotline species that can disperse aerially. Our results on spiders highlight that considering species‐specific life history traits helps to understand contrasting responses among species, and this may be essential for drawing general patterns of phenotypic changes among arthropods under anthropogenic warming. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Mimicry, the superficial resemblance between organisms of two or more species, is considered a textbook example for natural selection, for which it is assumed that predators are important selective agents. Ant mimicking spiders have received considerable attention in studies on mimicry because they include examples with remarkable, species‐specific morphological adaptations. Ant‐like behaviours such as erratic locomotory patterns, abdomen bobbing and vertical movements of the first or second pair of legs to imitate antennal movements, are assumed to have evolved before morphological mimicry and may be considered adaptations to general ant resemblance. Species‐specific behavioural ant mimicry (behaviour that is only observed in specific ants and imitated by their mimics) was very rarely documented and ant resembling behaviour that repels predator attacks has not been confirmed yet. In this study we report and discuss such species‐specific behaviour, a spray display (SD), in the castianeirine spiders Myrmecotypus iguazu (a morphologically accurate mimic of the carpenter ant Camponotus sericeiventris), and M. tahyinandu (a morphologically accurate mimic of C. crassus). The SD consisted of the raising of the cephalothorax and moving of the abdomen ventrally under the cephalothorax, pointing the apex forward, and holding the antennae (ant) or first pair of legs (spiders) at an angle of about 45°–120°. The morphological adaptations that are required to perform the SD and the lack of an alternative explanation for the purpose of this display suggest that the SD has evolved to enhance both general behavioural and morphologically accurate ant resemblance. The two observed Myrmecotypus species may be considered the behaviorally most accurate ant‐resembling spiders known to date, as the SD may provide protection against spider‐ and ant‐eating predators at a point in predator interactions where other myrmecomorph spiders may abandon their ant‐resembling behaviour. [ABSTRACT FROM AUTHOR]

We studied the spatial structure of spiders and beetles in 4 types of habitats in the Poloniny National Park. Between the years 2020 and 2021, we recorded 1,597 beetle specimens and 3,765 spider specimens using the pitfall trap method. The most represented beetles were Poecilus versicolor (53.4%), Nebria brevicollis (10.3%), Staphylinus caesareus (4.4%) and Amara familiaris (4.1%). Among the spiders, there were species Pardosa pullata (21.81%), Pachygnatha degeeri (14.21%), Xerolycosa nemoralis (10.28%), Pardosa palustris (7.86%), Trochosa ruricola (6.24%) and Alopecosa pulverulenta (4.38%). We confirmed the occurrence of two European important species of beetles (Carabus zawadzkii, Carabus variolosus) and 3 species of spiders belonging to the vulnerable species according to the IUCN threat status (Gongylidiellum vivum, Palliduphantes milleri and Xysticus lineatus). We also found the spider Micaria micans, which is new to the Slovak fauna and information about its distribution and habitat preferences in Slovakia is presented. Using multivariate analyzes (CCA, RDA) and classification species into bioindicative groups, we found a greater connection of adaptable and eurytopic species of ground beetles to the mesophilic meadow and of spiders to the habitat Nardetum pasture. Based on bioindicative groups of species (adaptable, eurytopic and relict), we found only a small difference in percentile points between spiders and beetles. [ABSTRACT FROM AUTHOR]

The intricate interplay between predators and prey has long fascinated ecologists, with bats and their diverse prey offering insight into co‐evolutionary dynamics. While bats have evolved sophisticated strategies for prey capture, they also face predation pressure. Among their predators, spiders stand out for their diversity of predatory tactics, ranging from hunting assaults and web ensnarement to the deployment of venom. Yet, bat predation records by spiders are mostly from tropical regions, and cases remain notably scarce in temperate regions. Here, we report four new incidences of bat predation and mortality by spiders and their webs in Europe. Our observations include detailed photograph and video documentation of the first record of a spider capturing and consuming a bat pup in Spain, as well as accounts of bats entangled in spider webs on a building and inside bat boxes in the United Kingdom. These findings shed light on understudied predator–prey dynamics, offering valuable insights into spider predation on bats in European ecosystems. Our study emphasises the importance of continued research to improve our understanding of ecological interactions between these elusive and primarily nocturnal taxa. [ABSTRACT FROM AUTHOR]

Spider silk—an environmentally friendly protein‐based material—is widely recognized for its extraordinary mechanical properties. Biomimetic spider silk‐like fibers made from recombinant spider silk proteins (spidroins) currently falls short compared to natural silks in terms of mechanical performance. In this study, it is discovered that spiders use structural conversion of molecular enhancers—conserved globular 127‐residue spacer domains—to make strong silk fibers. This domain lacks poly‐Ala motifs but interestingly contains motifs that are similar to human amyloidogenic motifs, and that it self‐assembles into amyloid‐like fibrils through a non‐nucleation‐dependent pathway, likely to avoid the formation of cytotoxic intermediates. Incorporating this spacer domain into a recombinant chimeric spidroin facilitates self‐assembly into silk‐like fibers, increases fiber molecular homogeneity, and markedly enhances fiber mechanical strength. These findings highlight that spiders employ diverse strategies to produce silk with exceptional mechanical properties. The spacer domain offers a way to enhance the properties of recombinant spider silk‐like fibers and other functional materials. [ABSTRACT FROM AUTHOR]

We describe the hitherto unknown male of Centromerus fuerteventurensis Wunderlich, 1992 and present new illustrations of the epigyne and vulva. We also provide an update on the known distribution of this species on the Canary Islands. [ABSTRACT FROM AUTHOR]

The arachnid fauna of the Maltese Islands has not yet been adequately investigated. In the present work, from a total of 117 species sampled, 36 taxa represent newly recorded spider species (Araneae) for Malta, with an additional new record of a harvestman (Opiliones). These new records include three new spider families and one new harvestman family for the Maltese archipelago: Anyphaenidae Bertkau, 1878, Mimetidae Simon, 1881, Oxyopidae Thorell, 1869 and Sclerosomatidae Simon, 1879; as well as two species which are recorded from Europe for the first time: Acartauchenius insigniceps (Simon, 1894) and Zelotes poecilochroaeformis Denis, 1937. Ecological, distributional, biogeographical and taxonomic notes are provided for the newly recorded species. [ABSTRACT FROM AUTHOR]

In Italy, the selenopid spider Selenops radiatus Latreille, 1819, was hitherto only known from the Aeolian Archipelago (northeastern Sicily), with a record from the island of Alicudi and plausible sightings from the island of Filicudi. In this paper, we present twentysix new records from Sicily sensu stricto and its satellite islands, consisting of observations gathered from online naturalist networks and one adult specimen collected from the area where most observations were made. Nearly all records were made in buildings or similar artificial habitats, supporting the hypothesis that occurrences of S. radiatus are mainly limited to synanthropic environments in Sicily. [ABSTRACT FROM AUTHOR]

The intricate interplay between predators and prey has long fascinated ecologists, with bats and their diverse prey offering insight into co‐evolutionary dynamics. While bats have evolved sophisticated strategies for prey capture, they also face predation pressure. Among their predators, spiders stand out for their diversity of predatory tactics, ranging from hunting assaults and web ensnarement to the deployment of venom. Yet, bat predation records by spiders are mostly from tropical regions, and cases remain notably scarce in temperate regions. Here, we report four new incidences of bat predation and mortality by spiders and their webs in Europe. Our observations include detailed photograph and video documentation of the first record of a spider capturing and consuming a bat pup in Spain, as well as accounts of bats entangled in spider webs on a building and inside bat boxes in the United Kingdom. These findings shed light on understudied predator–prey dynamics, offering valuable insights into spider predation on bats in European ecosystems. Our study emphasises the importance of continued research to improve our understanding of ecological interactions between these elusive and primarily nocturnal taxa. [ABSTRACT FROM AUTHOR]

A new genus, Turanobiusgen. n. (Araneae: Oecobiidae: Oecobiinae), is described from Iran and Central Asia, comprising the following four species: T. ferdowsii (Mirshamsi, Zamani and Marusik, 2017) comb. n. (♂; Iran, Kazakhstan), T. hissaricussp. n. (♂; Tajikistan), T. leptonychussp. n. (♂♀; Tajikistan), and T. tadzhikus (Andreeva and Tyshchenko, 1969) comb. n. (♂♀; Tajikistan); both new combinations are ex. Oecobius Lucas, 1846. Known distribution records of all four species are mapped. Additionally, a discussion is presented on the taxonomy of Oecobius and the potential revalidation of several genera currently considered synonymous with it. [ABSTRACT FROM AUTHOR]

Guilds have been used to assess how vegetation or environmental perturbations influence the community structure of animal communities. Spiders use a variety of hunting strategies. In arid environments they are the main predators of arthropods. Despite this, spider guilds have not been studied in desert ecosystems. Our study was carried out in one area of the Chihuahuan Desert. We used ramp-type traps and manual collection to capture the spiders. After identifying the specimens caught, we used a classification based on 20 and 23 traits to group the species into guilds. We used new traits for classification (eg horizontal web, triangular web, vertical web, threads coming out of the retreat). As a result, we obtained 11 guilds. Some species of the same family (e.g Gnaphosidae, Oxyopidae, Philodromidae, Theridiidae, Thomisidae) were positioned in different guilds. In addition to the classification, we provide information on the natural history of the species found. This information can be used to understand the differences between spider communities in desert vegetation types and those in other biomes. [ABSTRACT FROM AUTHOR]

Pardosa pseudoannulata is key predator in rice ecosystems; it plays a crucial role in rice pest biological control, effectively managing major rice pests such as rice planthopper. At present, there are few related studies on spiders' microRNA (miRNA). Consequently, we initiate a study on miR‐6826‐3p in P. pseudoannulata in response to high temperatures. First, we identified a total of 686 target genes of miR‐6826‐3p, 439 target genes had annotated results in the database, primarily involved in transcription and metabolism functions. Subsequently, quantitative real‐time PCR was employed to assess the relative expression levels of miR‐6826‐3p in P. pseudoannulata under different temperatures (31, 34, 37, 40°C) and various durations (1, 2, 4, 8, 12 h). The results revealed that compared to the control group (25°C), the relative expression level of miR‐6826‐3p in female spiders significantly increased under the same temperature and different duration stresses. The expression level of miR‐6826‐3p in male spiders showed an initial increase followed by a decrease trend, with relatively lower expression levels after 1 and 12 h at the same temperature conditions. Furthermore, under the same duration of stress, compared to the control group (25°C), the relative expression level of miR‐6826‐3p in female spiders significantly increased at different temperatures. These results demonstrate that P. pseudoannulata miR‐6826‐3p plays a significant role in response to high‐temperature stress. The research findings can provide a basis for future in‐depth studies on the miRNA functional of P. pseudoannulata, aiding in the elucidation of the regulatory mechanisms of P. pseudoannulata miRNAs in response to high‐temperature environments. [ABSTRACT FROM AUTHOR]

The well-known phenomenon of attracting untypical animals to disturbed territories has been poorly investigated in the polar mountains. We studied arthropod diversity in self-healing industrial clear-cuts and burn areas in the Khibiny Mountains, Kola Polar region. Fieldworks were conducted at four sites, including a control mountain taiga forest and its three transformed variants: burnt forest, uncleared clear-cut, and twice-disturbed burnt clear-cut. Arthropods were collected using formalin traps 2–3, 5–6, and 8–9 years after industrial deforestation in 2012 and an extensive grass-roots fire in 2013. Out of 124 identified species (spiders—61; ground beetles—41; and rove beetles—22), 79 (or 64%) were collected in disturbed, primarily burned areas and were absent in control forest. We note ten species of rove beetles, nine species of ground beetles, and eight species of spiders for the first time in the well-studied arthropod fauna of the Khibiny Mts. We found that grass-root fires transform the soil vegetation covers in the polar mountain forests more powerfully in comparison with extensive deforestation and attract a greater diversity of arthropods with different preferences, enriching the fauna of the polar mountains and the Subarctic region as a whole. The attraction effect persists for, at least, a decade after the violations. [ABSTRACT FROM AUTHOR]

Aim: We assessed the population genetic structure of the kleptoparasitic spider Argyrodes bonadea across the Southwestern Pacific islands. Our aim is to evaluate the impact of overseas distances and, in particular, the Kerama gap, as potential drivers of genetic differentiation. If no relationship exists, then we assume dispersal following adaptive change as alternative non‐vicariant mechanism that generates divergence. Location: Southwestern Pacific Islands. Taxon: Argyrodes bonadea. Methods: We used mitochondrial Cytochrome Oxidase 1 (CO1) gene sequences and Restriction Site‐associated DNA Sequencing (RAD‐seq) for our analyses. Results: Two strongly supported lineages, an Amami‐Okinawa Lineage (AOL) and an Austral‐Asia Lineage (AAL), correspond to two separate clades, roughly divided by the Kerama Gap, in phylogenetic trees estimated here. However, species delimitation led to the interpretation of only a single species present. The AOL exhibits complex, geographically structured host web spider species specificity, wherein the Amami population utilizes Cyrtophora, but AOL samples in Okinawa associate exclusively with Nephila—and yet all broadly distributed AAL populations show no evidence of host web spider species specificity. Main Conclusion: The population boundary between AOL and AAL likely results from local adaptation to novel hosts—instead of isolation by the Kerama Gap—following long‐distance dispersal and range expansion. Our results suggest kleptoparasitic spiders have the capacity to overcome permanent deep‐sea barriers and colonize distant landmasses. Whereas peripheral populations (AOL) demonstrate the capacity for specialization to a single host, which may have contributed to genetic differentiation and isolation, the broadly distributed AAL persists and has successfully expanded its geographical range as a host generalist, which may contribute to ongoing gene flow inferred in this study. [ABSTRACT FROM AUTHOR]

Many orb-web weaving spiders add highly visible zigzagging silk "decorations" to their webs that are thought to function in prey attraction or predator avoidance. Despite the long history of studies on the form, frequency, and function of these structures, little attention has been paid to their mode of construction. Here, we report for the first time the sequence of construction of decorations by Argiope luzona (Walckenaer, 1841), a common species in the northern Philippines. A disc-shaped decoration built by a juvenile was laid as several continuous loops in a modified figure-eight pattern. The resulting asymmetric design is typical of many Argiope spp., hence suggesting that disc decorations are built similarly across the genus. In a full cruciate decoration of an adult female spider -- consisting of four diagonal arms arrayed around the web's hub -- each two-armed diagonal was laid down in turn, each arm being laid from its outermost portion inward, the lower arm first. The mode of construction of the cruciate device suggests that this type of decoration evolved by duplication and diagonalizing the single two-armed vertical decoration seen in presumptively less derived Argiope. [ABSTRACT FROM AUTHOR]