Search

Characterization of fungal spider pathogens lags far behind their insect counterparts. In addition, little to nothing is known concerning the ecological reservoir and/or fungal entomopathogen community surrounding infection sites. Five infected spider cadavers were identified in the neo-tropical climate of north-central Florida, USA, from three of which viable cultures were obtained. Multi-locus molecular phylogenetic and morphological characterization identified one isolate as a new Gibellula species, here named, Gibellula floridensis, and the other isolates highly similar to Parengyodontium album. The fungal entomopathogen community surrounding infected spiders was sampled at different habitats/trophic levels, including soil, leaf litter, leaf, and twig, and analyzed using ITS amplicon sequencing. These data revealed broad but differential distribution of insect-pathogenic fungi between habitats and variation between sites, with members of genera belonging to Metarhizium and Metacordyceps from Clavicipitaceae, Purpureocillium and Polycephalomyces from Ophiocordyceps, and Akanthomyces and Simplicillium from Cordycipitaceae predominating. However, no sequences corresponding to Gibellula or Parengyodontium, even at the genera levels, could be detected. Potential explanations for these findings are discussed. These data highlight novel discovery of fungal spider pathogens and open the broader question regarding the environmental distribution and ecological niches of such host-specific pathogens. [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]

Silkworms and spiders are capable of generating fibers that are both highly durable and elastic in a short span of time, using a silk solution stored within their bodies at room temperature and normal atmospheric pressure. The dragline silk fiber, which is essentially a spider's lifeline, surpasses the strength of a steel wire of equivalent thickness. Regrettably, humans have yet to replicate this process to produce fibers with similar high strength and elasticity in an eco-friendly manner. Therefore, it is of utmost importance to thoroughly comprehend the extraordinary structure and fibrillation mechanism of silk, and leverage this understanding in the manufacturing of high-strength, high-elasticity fibers. This review will delve into the recent progress in comprehending the structure of silks derived from silkworms and spiders, emphasizing the distinctive attributes of solidstate NMR. [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]

Three modules viz., M1 - integrated pest management (IPM) module, M2 - bio-intensive pest management (BIPM) module and M3 - farmer’s routine pest management module formulated against insect pests of okra were evaluated simultaneously at two locations to know their impact on spider and coccinellid predators. Seven and two species of spiders and coccinellids, respectively, were recorded. Pooled data revealed that BIPM module was found to be safe for the predators. [ABSTRACT FROM AUTHOR]

The Burmese lynx spider, Oxyopes birmanicus Thorell (Araneae: Oxyopidae) is one of the endemic and entomophagous predatory arthropod species in India. This present study describes the seasonal abundance, vertical distribution, and feeding behaviour of O. birmanicus on nymph (4th/5th instar) and the adults of the tea mosquito bug, Helopeltis theivora Waterhouse (Hemiptera: Miridae) under laboratory conditions. The seasonal abundance of the O. birmanicus spider was considerably high from June to November and low from January to April. The abundance of O. birmanicus significantly correlated with the TMB infestation percentage. In a vertical distribution study, the O. birmanicus spider largely preferred the top level of the tea bush, the observed population was shared by the top and middle levels with 76% and 24% respectively. The feeding potential of the female O. birmanicus spider was significantly higher than the male and egg-guarding female. Both, male and egg-guarding female O. birmanicus showed on-par feeding efficacy. The study found that O. birmanicus was an efficient predator against TMB and the results may be useful in developing an integrated pest management strategy for TMB. [ABSTRACT FROM AUTHOR]

Background: Only two Otacilia Thorell, 1897 species with troglobitic characteristics have been recorded from Laos and no records of troglobitic Otacilia species from China. New information: A new troglobitic species is reported from Guangxi, China: Otacilia khezu Lin & Li, sp. nov. (♂♀). Photos and morphological descriptions of the new species are presented; the type specimens of the new species are deposited in the Institute of Zoology, Chinese Academy of Sciences (IZCAS), Beijing. [ABSTRACT FROM AUTHOR]

Spiders are a diverse order of chelicerates that diverged from other arthropods over 500 million years ago. Research on spider embryogenesis, particularly studies using the common house spider Parasteatoda tepidariorum, has made important contributions to understanding the evolution of animal development, including axis formation, segmentation, and patterning. However, we lack knowledge about the cells that build spider embryos, their gene expression profiles and fate. Single-cell transcriptomic analyses have been revolutionary in describing these complex landscapes of cellular genetics in a range of animals. Therefore, we carried out single-cell RNA sequencing of P. tepidariorum embryos at stages 7, 8 and 9, which encompass the establishment and patterning of the body plan, and initial differentiation of many tissues and organs. We identified 20 cell clusters, from 18.5 k cells, which were marked by many developmental toolkit genes, as well as a plethora of genes not previously investigated. We found differences in the cell cycle transcriptional signatures, suggestive of different proliferation dynamics, which related to distinctions between endodermal and some mesodermal clusters, compared with ectodermal clusters. We identified many Hox genes as markers of cell clusters, and Hox gene ohnologs were often present in different clusters. This provided additional evidence of sub- and/or neo-functionalisation of these important developmental genes after the whole genome duplication in an arachnopulmonate ancestor (spiders, scorpions, and related orders). We also examined the spatial expression of marker genes for each cluster to generate a comprehensive cell atlas of these embryonic stages. This revealed new insights into the cellular basis and genetic regulation of head patterning, hematopoiesis, limb development, gut development, and posterior segmentation. This atlas will serve as a platform for future analysis of spider cell specification and fate, and studying the evolution of these processes among animals at cellular resolution. [ABSTRACT FROM AUTHOR]

The web-building skills of spiders made them strong from the evolutionary aspect. Spider webs are used in hunting, building nests, setting traps, and movement. The structure of web architecture, that of adhesive materials being produced, and that of cribellate offer important clues in order to understand their hunting behaviors. Spiders have different silk-spinning apparatuses, allowing them to produce different types of silk fibrils. While some spider species rely on webs for survival in nature, others can survive without them. Even though basic taxonomic features remain constant, the silk-spinning apparatuses of spiders might be subjected to adaptive variations. In the present study, the structural organization of the silk-spinning apparatus and the web architecture of the web-maker spider Uloborus walckenaerius Latreille, 1806 were observed by making use of scanning electron microscopy (SEM). The web structure of U. walckenaerius, the characteristics of the spinnerets, especially the posterior spinneret, and the arrangement of the spigots are reported in this study. Adaptations of the silk-spinning apparatus, which has provided an evolutionary success to U. walckenaerius, were also analyzed. It was determined that the web structure consisted of very fine nanofibers and, differing from other groups, there also were crimped silk fibrils. [ABSTRACT FROM AUTHOR]

Four new species of the genus Camptoscaphiella Caporiacco, 1934 are described from Xizang, China, i.e., C. metok Tong & Li, sp. nov. (♂), C. shannan Tong & Li, sp. nov. (♂♀), C. trifoliata Tong & Li, sp. nov. (♂♀) and C. zayu Tong & Li, sp. nov. (♂♀). Morphological descriptions, photographic illustrations and a distribution map of the four new species are given. [ABSTRACT FROM AUTHOR]

The Nearctic family Hahniidae is seldom found in South America; only 20 species occur on the continent. Herein, we present the first record of the family in mainland Ecuador, with the description of thirteen new species in five different genera. In Amaloxenops: A. minimalista n. sp. (female); in Kasha n. gen.: Kasha patpa n. sp. (male, female); in Neohahnia: Neohahnia catleyi (female) n. sp., N. piemontana n. sp. (male, female), N. pristirana n. sp. (male, female), N. freibergi n. sp. (male, female), N. paramo n. sp. (male, female), and N. chalupas n. sp. (male); in Paramito n. gen.: Paramito papallacta n. sp. and P. oyacachi n. sp.; and in Pristirana n. gen.: Pristirana barthlotti n. sp. (male, female), P. niederi n. sp. (female), and P. nowickii n. sp. (male, female). Distribution maps are presented for all species, as well as a key to the South American Hahniidae genera. [ABSTRACT FROM AUTHOR]

Climate change is disproportionately impacting the North, and northern arthropods are particularly vulnerable to disturbances. The Dempster Highway is a gravel road that crosses the northern Yukon Territory in Canada, and wolf spiders (Araneae: Lycosidae) are the top arthropod predators on the tundra in this region. We investigated the effects of the Dempster Highway on subarctic tundra wolf spider abundance, phenology, and community composition by actively sampling 8 paired plots near (20 m) and far (200 m) from the road. Species richness did not differ with distance from the road, but total wolf spider abundance was much lower near the road, and this was driven by decreased abundance of the dominant tundra wolf spider species, Pardosa lapponica (Thorell, 1872). The overall proportion of females carrying egg sacs was higher near the road, suggesting advanced phenology in response to increased temperatures near the road. Together, these results indicate that the Dempster Highway impacts tundra wolf spider communities, which may have important consequences for food web dynamics and ecosystem function. Les changements climatiques ont un impact plus important sur le Nord, et les arthropodes nordiques sont particulièrement vulnérables aux perturbations. La route Dempster est une route de gravier qui traverse le nord du territoire du Yukon au Canada, et les araignées-loups (Araneae: Lycosidae) sont d'importants prédateurs d'arthropodes de la toundra de cette région. Nous avons étudié les effets de la route Dempster sur l'abondance, la phénologie et la composition de la communauté des araignées-loups de la toundra subarctique en échantillonnant activement huit parcelles appariées proches (20 m) et éloignées (200 m) de la route. La richesse des espèces ne différait pas avec la distance par rapport à la route, mais l'abondance totale d'araignées-loups était inférieure près de la route, et cela peut être attribué à une diminution de l'abondance de l'espèce dominante d'araignées-loups de la toundra, Pardosa lapponica (Thorell, 1872). La proportion globale des femelles portant des cocons était plus élevée près de la route, suggérant une phénologie avancée en réponse à l'augmentation des températures près de la route. Ces résultats indiquent que, globalement, la route Dempster a un impact sur les communautés d'araignées-loups de la toundra, ce qui peut avoir des conséquences importantes sur la dynamique du réseau trophique et le fonctionnement de l'écosystème. [ABSTRACT FROM AUTHOR]

Due to the unique properties of the silk fibroin (SF) made from silkworm, SF-based hydrogels have recently received significant attention for various biomedical applications. However, research on the SF-based hydrogels isolated from spider silks has been rtricted due to the limited collection and preparation of naïve silk materials. Therefore, this study focused on the microstructural characteristics of hydrogel scaffolds derived from two types of woven silk glands: the major ampullate gland (MAG) and the tubuliform gland (TG), in the orb-web spider Trichonephila clavate. We compared these spider glands with those of the silk fibroin (SF) hydrogel scaffold extracted from the cocoon of the insect silkworm Bombyx mori. Our FESEM analysis revealed that the SF hydrogel has high porosity, translucency, and a loose upper structure, with attached SF fibers providing stability. The MAG hydrogel displayed even higher porosity, as well as elongated fibrous structures, and improved mechanical properties: while the TG hydrogel showed increased porosity, ridge-like or wall-like structures, and stable biocapacity formed by physical crosslinking. Due to their powerful and versatile microstructural characteristics, the MAG and TG hydrogels can become tailored substrates, very effective for tissue engineering and regenerative medicine applications. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) are conserved noncoding small RNAs that play essential regulatory roles in gene function by regulating target genes. Pardosa pseudoannulata is an important natural predatory enemy of insect pests and plays a significant role in controlling pests in rice fields, with temperature having a significant impact on their growth and development. To understand the response of miRNAs to temperature stress in P. pseudoannulata, we performed miRNA identification analyses of adult spiders exposed to 10°C and 40°C for 12 h, as low‐temperature and high‐temperature treatment groups, respectively. We obtained 54.74 M clean reads from 69.84 M raw reads after filtering out low‐quality reads, and 78 miRNAs including 13 novel miRNAs were identified from three small RNA libraries (10°C, 25°C and 40°C). At the low temperature and the high temperature, eight (one upregulated and seven downregulated) and ten (nine upregulated and one downregulated) differentially expressed miRNAs were identified, respectively. These differentially expressed miRNAs negatively regulated 43 and 12 target mRNA (the unigenes in our previous transcriptome sequence data) in response to low‐ and high‐temperature stress, respectively. These target genes are mainly involved in translation, ribosome structure and biotransformation, as well as the generation and conversion of energy. This study represents the first report of miRNA identification related to the Araneae spider species in response to temperature stress. These results will greatly facilitate our understanding of the physiological and biochemical mechanisms of spiders in response to temperature stress, which might be beneficial for the conservation and utilization of this species as an important natural insect enemy of pests in rice ecosystems. [ABSTRACT FROM AUTHOR]

A cave represents a subterranean ecosystem that harbours a myriad of unique, peculiar, and secluded flora and fauna. These biotas have evolved with a wide range of ecological adaptations that allow them to thrive in harsh environments with limited light. Gua Kelam 1 constitutes part of the Gua Kelam limestone caves system in the Nakawan Range of Perlis State Park, Malaysia. Previous observations indicated that it harbours a plethora of spider species; however, their existence is still elusive as speleobiological studies remain unexplored. Herein, we identified the cavernicolous spiders found in the dark zone areas of Gua Kelam 1 through a complementary approach based on morphology and DNA barcoding. From the morphological analysis, we described three web-building spiders of JTKK2 and JTKK3 groups down to the species-level to belong to Nephilengys malabarensis, and Orsinome vethi except for Pholcus sp. from JTKK4 individuals. The molecular analysis of the cytochrome oxidase-I (COI) genes of JTKK2 and JTKK3 individuals showed that they exhibited a high degree similarity with N. malabarensis (98.3%), and O. vethi (100.0%), respectively except for JTKK4 individuals with only 91.4% homology with P. kuhapimuk. Phylogenetic analysis also generated a congruent tree, in which the identified species are well nested within the family Araneidae, Tetragnathidae, and Pholcidae. By this integral approach, the three spiders were determined as N. malabarensis, O. vethi, and Pholcus sp. These spiders are originally epigean in their habitat but uniquely thrive in Gua Kelam 1. [ABSTRACT FROM AUTHOR]

The type material of Xenesthis colombiana Simon, 1891, X. immanis Ausserer, 1875, and X. monstrosa Pocock, 1903, are redescribed, with additional specimens of X. colombiana recorded. A neotype is designated for Xenesthis intermedia Schiapelli and Gerschman, 1945, as the holotype is lost; the female is redescribed, and the male is described for the first time. A new species, Xenesthis avanzadora sp. nov., is described from Venezuela based on a holotype male. [ABSTRACT FROM AUTHOR]

Thermal preference and thermal performance are used to describe the thermal biology of an ectothermic organism through parameters, i.e., estimating locomotor performance by maximum running speed. In this study, we assessed the thermal preference and locomotor performance of the spider Mecicobothrium thorelli Holmberg, 1882, a wintry mygalomorph spider endemic to the native mountainous grasslands of central Argentina and Uruguay. The preferred temperatures of the 72.4% of the individuals were in the range of 10–20 °C. The highest frequencies of preferred temperatures were 10–15 °C in males and 15–20 °C in females. The sprint speed showed significant differences between all the temperatures evaluated and showed the highest speeds at 25 °C and the lowest at 3 °C. The optimal temperature was 26.09 °C, which was significantly higher than the preferred temperature in both males and females. We concluded that M. thorelli selects a wide range of temperatures and prefers to stay in medium and low temperatures, which are correlated with winter activity in the wild. However, the species showed maximum speed at higher temperatures, which implies that spiders would perform even better in nature and maximize their locomotion by being active during a warmer period. [ABSTRACT FROM AUTHOR]

Jumping spiders (Araneae: Salticidae) possess a visual system that is exceptional among arthropods, mainly due to its unmatched acuity. Although vision of these spiders has been studied for decades, some of its main aspects remain unclear. One such aspect is the light spectrum visible to salticids, which is surprisingly heterogenous and involves various underlying physiological mechanisms. The results of the behavioral experiments with the regal jumping spider (Phidippus regius) presented in this study provide evidence that these vision-dependent spiders are able to capture their prey even under red (longwave) light, which is usually not perceived by spiders. Broader use of this experimental design in studies of spider vision is discussed. [ABSTRACT FROM AUTHOR]

Eleven new species from the Scytodoidea group are described from mainland Ecuador: in the family Drymusidae, Drymusa pristirana sp. nov. (female) and in the family Scytodidae, Scytodes amazonica sp. nov. (male, female); S. argelia sp. nov. (female), S. ayampe sp. nov. (female), S. choco sp. nov. (male, female), S. costa sp. nov. (female), S. jaguar sp. nov. (male), S. loja sp. nov. (female), S. minus sp. nov. (male); S. orellana sp. nov. (male, female); and S. tayos sp. nov. (male). The new species D. pristirana sp. nov. presents a unique morphological character on the ventral surface of the female abdomen. The type specimens of S. lineatipesTaczanowski, 1874 from French Guiana and S. luteola Simon, 1893 from Venezuela are imaged for the first time, and S. romitii Caporiacco, 1947 is removed from synonymy with S. lineatipes. [ABSTRACT FROM AUTHOR]

Gene duplication generates new genetic material that can contribute to the evolution of gene regulatory networks and phenotypes. Duplicated genes can undergo subfunctionalization to partition ancestral functions and/or neofunctionalization to assume a new function. We previously found there had been a whole genome duplication (WGD) in an ancestor of arachnopulmonates, the lineage including spiders and scorpions but excluding other arachnids like mites, ticks, and harvestmen. This WGD was evidenced by many duplicated homeobox genes, including two Hox clusters, in spiders. However, it was unclear which homeobox paralogues originated by WGD versus smaller-scale events such as tandem duplications. Understanding this is a key to determining the contribution of the WGD to arachnopulmonate genome evolution. Here we characterized the distribution of duplicated homeobox genes across eight chromosome-level spider genomes. We found that most duplicated homeobox genes in spiders are consistent with an origin by WGD. We also found two copies of conserved homeobox gene clusters, including the Hox, NK, HRO, Irx , and SINE clusters, in all eight species. Consistently, we observed one copy of each cluster was degenerated in terms of gene content and organization while the other remained more intact. Focussing on the NK cluster, we found evidence for regulatory subfunctionalization between the duplicated NK genes in the spider Parasteatoda tepidariorum compared to their single-copy orthologues in the harvestman Phalangium opilio. Our study provides new insights into the relative contributions of multiple modes of duplication to the homeobox gene repertoire during the evolution of spiders and the function of NK genes. [ABSTRACT FROM AUTHOR]

Background: The spider genus Liphistius Schiødte, 1849 contains 69 species, endemic to Indochina and Southeast Asia. Only one species is currently known from the Chinese province of Yunnan: Liphistius nabang Yu, Zhang & Zhang, 2021. New information: A new species, Liphistius liz Lin & Li, sp. nov., is described from Yunnan, China, on the basis of both sexes. Photos and a morphological description of the new species are provided. [ABSTRACT FROM AUTHOR]

Three new species of Grandilithus Liu & Li, 2022 are described from southern China on the basis of both sexes: G. chongzuo sp. nov. from Guangxi, G. xiaohuangshan sp. nov. from Guangdong and G. lanxi sp. nov. from Jiangxi. A distribution map of these three species is provided. [ABSTRACT FROM AUTHOR]

The amaurobiid spider species Amaurobius strandi Charitonov, 1937 is recorded for the first time from Türkiye. Its characteristic features and photographs are presented. This new record increases the total number of species of family Amaurobiidae in Türkiye to six species. [ABSTRACT FROM AUTHOR]

Five new spider species of the genus Pholcus Walckenaer, 1805, P. duryun sp. nov., P. hwaam sp. nov., P. mohang sp. nov., P. worak sp. nov., and P. yangpyeong sp. nov., belonging to the P. phungiformes group in the family Pholcidae C. L. Koch, 1850, are newly described from South Korea. These new species were collected from mixed forests in mountainous, hilly, and coastal terrains. This study provides the diagnoses, detailed descriptions, distribution maps, and taxonomic photographs of these new species. [ABSTRACT FROM AUTHOR]

Argiope bruennichi, the European wasp spider, has been investigated intensively as a focal species for studies on sexual selection, chemical communication, and the dynamics of rapid range expansion at a behavioral and genetic level. However, the lack of a reference genome has limited insights into the genetic basis for these phenomena. Therefore, we assembled a high-quality chromosome-level reference genome of the European wasp spider as a tool for more in-depth future studies. We generated, de novo, a 1.67 Gb genome assembly of A. bruennichi using 21.8× Pacific Biosciences sequencing, polished with 19.8× Illumina paired-end sequencing data, and proximity ligation (Hi-C)-based scaffolding. This resulted in an N50 scaffold size of 124 Mb and an N50 contig size of 288 kb. We found 98.4% of the genome to be contained in 13 scaffolds, fitting the expected number of chromosomes (n = 13). Analyses showed the presence of 91.1% of complete arthropod BUSCOs, indicating a high-quality assembly. We present the first chromosome-level genome assembly in the order Araneae. With this genomic resource, we open the door for more precise and informative studies on evolution and adaptation not only in A. bruennichi but also in arachnids overall, shedding light on questions such as the genomic architecture of traits, whole-genome duplication, and the genomic mechanisms behind silk and venom evolution.

The presence of the spider genus Thyreosthenius Simon, 1884 (Linyphiidae) is for the first time confirmed in the Iberian Peninsula with an observation of the myrmecophile species T. biovatus (O. Pickard-Cambridge, 1875). Four adult females and two sub-adult male specimens were collected inside mound nests belonging to the red wood ant species Formica lugubris Zetterstedt, 1838 in the Aragon and Catalonia regions of Spain. This represents the second known record of an occurrence of T. biovatus in association with F. lugubris, and the first for Continental Europe. In addition, the existing information on the host preference of this species is reviewed and discussed in relation to the new data from the Spanish Pyrenees. [ABSTRACT FROM AUTHOR]

The wandering spider, Phoneutria depilata, is one of Colombia's most active nocturnal arthropod predators of vertebrates and invertebrates. Its venom has been a relevant subject of study in the last two decades. However, the scarcity of transcriptomic data for the species limits our knowledge of the distinct components present in its venom for linking the mainly neurotoxic effects of the spider venom to a particular molecular target. The transcriptome of the P. depilata venom gland was analyzed to understand the effect of different diets or sex and the impact of these variables on the composition of the venom. We sequenced venom glands obtained from ten males and ten females from three diet treatments: (i) invertebrate: Tenebrio molitor, (ii) vertebrate: Hemidactylus frenatus, and (iii) mixed (T. molitor + H. frenatus). Of 17,354 assembled transcripts from all samples, 65 transcripts relating to venom production differed between males and females. Among them, 36 were classified as neurotoxins, 14 as serine endopeptidases, 11 as other proteins related to venom production, three as metalloprotease toxins, and one as a venom potentiator. There were no differences in transcripts across the analyzed diets, but when considering the effect of diets on differences between the sexes, 59 transcripts were differentially expressed. Our findings provide essential information on toxins differentially expressed that can be related to sex and the plasticity of the diet of P. depilata and thus can be used as a reference for venomics of other wandering spider species. [ABSTRACT FROM AUTHOR]

The gnaphosid spider genus Sernokorba Kamura, 1992 is reviewed. While Sernokorba pallidipatellis (Bösenberg and Strand 1906) and Sernokorba fanjing Song, Zhu & Zhang, 2004, occur in the Far East and the Japanese archipelago, Sernokorba tescorum (Simon, 1914) is known from Europe. We here describe a fourth species, Sernokorba betyar sp. nov. (male and female) from the forest steppe vegetation in southern Hungary in Central Europe. Digital images, comparative drawings (except for S. fanjing) and a distribution map are provided for all the species, and an identification key is compiled. The cheliceral dentation as diagnostic character and its interpretation are discussed. [ABSTRACT FROM AUTHOR]

To assess the immune potential of spiders, in the present study juvenile and adult females of Parasteatoda tepidariorum were exposed to Bacillus subtilis infection, injury by a nylon monofilament and a combination of both. The expression level of selected immune-related genes: defensin 1 (PtDEF1), lysozyme 1 (PtLYS1), lysozyme C (PtLYSC), lysozyme M1 (PtLYSM1), autophagy-related protein 101 (PtATG101), dynamin (PtDYN) and heat shock proteins (HSP70) (PtHSPB, PtHSPB2A, PtHSPB2B), production of lysozyme and HSP70 proteins, and hemocytes viability were measured. The obtained results indicated expression of the lysozyme, autophagy-related protein and HSP70 genes in both ontogenetic stages of P. tepidariorum. It has been also shown that the simultaneous action of mechanical and biological factors causes higher level of lysozyme and HSP70, cell apoptosis intensity and lower level of hemocytes viability than in the case of exposure to a single immunostimulant. Moreover, mature females showed stronger early immune responses compared to juveniles. [ABSTRACT FROM AUTHOR]

The first formal record of Eucratoscelus pachypus Schmidt & von Wirth, 1990 from Kenya is reported, based on observation of a female on the western slopes of the Chyulu Hills by the second author. This charismatic species is easily identified based on photographs. [ABSTRACT FROM AUTHOR]

Spider specimens were collected by using aspirator, sweep net, and pitfall traps from Kelkit Valley, located in Central Anatolia and Black Sea regions between April and November in 2019-2021. A total of 203 species belonging to 131 genera in 31 families were recorded from the study area. All identified species are new records for the study area. All specimens were labelled and preserved as museum material in Arachnology Museum of Niğde Ömer Halisdemir University. [ABSTRACT FROM AUTHOR]

The toxicity of pesticides to organisms depends on the total amount of chemical exposure. Toxicity can be minimized if the organism recognizes the pesticide and alters its behavior. Furthermore, the physical barrier of cuticular hydrocarbons can prevent the entrance of the pesticide into the organism. Finally, if the pesticide enters the body, the organism experiences physiological changes favoring detoxification and the maintenance of homeostasis. We analyzed the behavioral and metabolic response of the spider Polybetes pythagoricus at different times of exposure to the organophosphate pesticide chlorpyrifos. First we observed that the individuals are capable of recognizing and avoiding surfaces treated with pesticides based on a behavioral analysis. Subsequently, we characterized cuticular hydrocarbons as a possible barrier against pesticides. Then we observed that the pesticide provoked histological damage, mainly at the level of the midgut diverticula. Finally, we analyzed the activity of several of the spider's enzymes linked to oxidative stress after exposure to chlorpyrifos for different lengths of time (6, 24, and 48 h). We observed that catalase activity was high at the start, whereas the activity of superoxide dismutase and glutathione S‐transferase changed significantly at 48 h. Lipid peroxidation became high at 6 h, but decreased at 48 h. In conclusion, although P. pythagoricus can avoid contact with chlorpyrifos, this pesticide causes activation of the antioxidant system when it enters the body. Our results make a significant contribution to the ecotoxicology of spiders. Environ Toxicol Chem 2023;42:1293–1308. © 2023 SETAC [ABSTRACT FROM AUTHOR]

Background: Only one zodariid species, Storenomorpha lushanensis Yu & Chen, 2009 was found from Jiangxi Province. No other Mallinella species have been recorded from this Province. New information: A new species, Mallinella shahu sp. n. is described from Jiangxi Province, China. Morphological illustrations, living photos and distribution map are given. [ABSTRACT FROM AUTHOR]

In this study, spider fauna of Çeşme, Karaburun and Urla districts in the İzmir Peninsula were investigated. Examined specimens were collected from various localities in the region between December 2016 and April 2018. As a result of the study, 497 adult spider specimens (299 ♀♀, 198 ♂♂) were collected; 88 genera and 109 species belonging to 33 families were identified. Of these species, since five individuals belonging to different families are juvenile, their identification is left at the genus level. All species are new records for İzmir Peninsula except: Argyrodes argyrodes (Walckenaer, 1841), Dipoena galilaea Levy & Amitai, 1981, Dysdera fragaria Deeleman-Reinhold, 1988, Scytodes thoracica (Latreille, 1802), Scytodes velutina Heineken & Lowe, 1832, Tetragnatha nitens (Savigny, 1825) and Thanatus pictus L. Koch, 1881. [ABSTRACT FROM AUTHOR]

The selection of explanatory variables is very important in a species distribution model for predicting changes in the distribution of organisms caused by climate change. In this study, a two-dimensional prediction of the abundance and distribution of beetles and spiders using temperature and precipitation was compared with the results of previous studies that employed a one-dimensional prediction using temperature. This study used the data from previous surveys for 366 forest sites in South Korea between 2006 and 2009 using pitfall traps. Species distribution models were created for 51 species with a high occurrence (collected from more than 10% of the total sites). A generalized additive model (GAM) was used for the distribution models. The future abundance and distribution based on climate scenarios RCP 4.5 and 8.5 were predicted by selecting 35 species from 51 common species for which climatic factors (temperature and precipitation) had a significant effect on abundance and distribution. In a two-dimensional prediction using temperature and precipitation, the range of change was larger compared with a one-dimensional prediction using temperature, and precipitation had a significant effect on decreasing species. [ABSTRACT FROM AUTHOR]

The agelenid spider species Tegenaria pseudolyncea (Guseinov, Marusik & Koponen, 2005) is reported for the first time from Türkiye. The morphological characters and palpal organ of this species were photographed. The locality record where the species was collected is indicated on a map. [ABSTRACT FROM AUTHOR]

The phonognathid spider species Leviellus kochi (Thorell, 1870) is reported for the first time from Türkiye. Its general habitus and genitalia are illustrated. Brief description and collecting data of this species are also given. [ABSTRACT FROM AUTHOR]

The water-soluble glue substance of the capture threads in Trichonephila clavata is solely produced from two pairs of aggregate silk glands. During the web glue production, secretory vesicles were synthesized via the extensive rough endoplasmic reticulum of epithelial cells. Unlike the clearly described fibrous web production in spiders, the process of aqueous web glue production appears to involve either a condensing or a packaging step by the Golgi complex. In particular, the fine structure of secretory vesicles varies from cell to cell and may represent the secretory cycle. The electron-dense multivesicular bodies were clearly visible as discrete droplets, and the mature secretory product in the glandular epithelium appeared as a spherical vacuole grown by fusion with surrounding small vesicles. Our fine structural observation reveals that the secretion occurs when the release of secreted material involves the loss of part of the cytoplasm. The bleb along the luminal surface of the secretory cells and membrane-bound extracellular vesicles which pinched off from the cell suggests that the secretory product is released by the mechanism of apocrine secretion. [ABSTRACT FROM AUTHOR]

Cell migration is a fundamental component during the development of most multicellular organisms. In the early spider embryo, the collective migration of signalling cells, known as the cumulus, is required to set the dorsoventral body axis. Here, we show that FGF signalling plays an important role during cumulus migration in the spider Parasteatoda tepidariorum. Spider embryos with reduced FGF signalling show reduced or absent cumulus migration and display dorsoventral patterning defects. Our study reveals that the transcription factor Ets4 regulates the expression of several FGF signalling components in the cumulus. In conjunction with a previous study, we show that the expression of fgf8 in the germ-disc is regulated via the Hedgehog signalling pathway. We also demonstrate that FGF signalling influences the BMP signalling pathway activity in the region around cumulus cells. Finally, we show that FGFR signalling might also influence cumulus migration in basally branching spiders and we propose that fgf8 might act as a chemo-attractant to guide cumulus cells towards the future dorsal pole of the spider embryo. [Display omitted] • FGFR signalling mediates DV-axis formation in the common house spider P. tepidariorum. • Cumulus cell migration requires the expression of fgf8. • FGFR signalling influences BMP signalling in the embryonic germ-disc. • fgf8 expression relies on the activity of the Hh signalling pathway. • Ets4 regulates the expression FGFR signalling components in the cumulus. [ABSTRACT FROM AUTHOR]

Venom expressed by the nearly 50,000 species of spiders on Earth largely remains an untapped reservoir of a diverse array of biomolecules with potential for pharmacological and agricultural applications. A large fraction of the noxious components of spider venoms are a functionally diverse family of structurally related polypeptides with an inhibitor cystine knot (ICK) motif. The cysteine-rich nature of these toxins makes structural elucidation difficult, and most studies have focused on venom components from the small handful of medically relevant spider species such as the highly aggressive Brazilian wandering spider Phoneutria nigriventer. To alleviate difficulties associated with the study of ICK toxins in spiders, we devised a comprehensive approach to explore the evolutionary patterns that have shaped ICK functional diversification using venom gland transcriptomes and proteomes from phylogenetically distinct lineages of wandering spiders and their close relatives. We identified 626 unique ICK toxins belonging to seven topological elaborations. Phylogenetic tests of episodic diversification revealed distinct regions between cysteine residues that demonstrated differential evidence of positive or negative selection, which may have structural implications towards the specificity and efficacy of these toxins. Increased taxon sampling and whole genome sequencing will provide invaluable insights to further understand the evolutionary processes that have given rise to this diverse class of toxins. [ABSTRACT FROM AUTHOR]

SPIDER is the 100 keV full-size Negative Ion Source prototype of the ITER Neutral Beam Injector, operating at Consorzio RFX in Padova, Italy. The largest Negative Ion Source in the world, SPIDER generates an RF driven plasma from which Deuterium or Hydrogen negative ions are produced and extracted. At the end of 2021, a scheduled long-term shutdown started to introduce major modifications and improvements aiming to solve issues and drawbacks identified during the first three years of SPIDER operations. The first action of the shutdown period was the disassembly and characterization of the SPIDER beam source after removal from the vacuum vessel and its placement inside the clean room. Each component was carefully assessed and catalogued, following a documented procedure. Some source components, i.e., the Plasma Grid, Extraction Grid and Bias Plate, revealed the presence of different and non-uniform red, white and green coatings that might be correlated to back-streaming positive ions impinging on grid surfaces, electrical discharges and caesium evaporation. Thus, several analyses have been carried out to understand the nature of such coatings, with the study still ongoing. The evidence of caesium evaporation and deposition on molybdenum-coated SPIDER components, such as the formation of oxides and hydroxides, is demonstrated through surface characterization analyses with the use of the Scanning Electron Microscope (SEM), X-ray Diffraction (XRD) and X-ray Photoelectron Spectroscopy (XPS). [ABSTRACT FROM AUTHOR]

Brazil is the country with the most diverse tarantula (Theraphosidae) fauna, having 215 described species. Vitalius Lucas, Silva Júnior & Bertani, 1993 is one of the most diverse and common genera in Southern, Southeastern and Central-West regions of Brazil with ten described species. Individuals of Vitalius species are large and widespread in areas of the Brazilian Atlantic Forest. A single species is known to occur in areas of Cerrado vegetation. Herein, two new species are described from areas of restinga, coastal areas typically with low vegetation and sandy soil, in the coast of the states of Rio de Janeiro (Vitalius restinga sp. nov.), Bahia and Sergipe (Vitalius sapiranga sp. nov.). Males and females of these two new species have a much longer than wide sternum. Males have a short apical keel in the male palpal bulb. The two species can be distinguished by embolus width, slender in V. restinga sp. nov. and thicker in V. sapiranga sp. nov. Females can be distinguished by the spermathecae shape, slender in V. restinga sp. nov. and broader in V. sapiranga sp. nov. These are the first known theraphosids endemic to Brazilian Atlantic Coast restingas. Biological data indicate V. sapiranga sp. nov. and maybe V. restinga sp. nov. commonly use bromeliads as retreats. It is herein hypothesized they are sister species occupying similar habitats in Brazilian coast, but separated by ca. 1,000 kilometers. [ABSTRACT FROM AUTHOR]

Introduction: Fear is associated with perceptual biases. People who are afraid of spiders perceive spiders as larger than people without this fear. It is yet unclear, however, whether this effect can be influenced by using implicit (non-deliberate) emotion regulation (ER) processes and explicit (deliberate) ER strategies, such as reappraisal and suppression. Method: This study examined the link between implicit and explicit ER and size estimation among women afraid of spiders. After performing an implicit ER (cognitive control) task, participants rated the size and valence of spiders, wasps and butterflies shown in pictures. Participants' tendency to use reappraisal and suppression was assessed using the Emotion Regulation Questionnaire. Results: Results showed no effect of implicit ER on size and valence ratings. A greater tendency to use reappraisal was linked to reduced negative feelings on seeing the pictures of spiders. Greater use of suppression, however, was linked to increased size estimation of the spider stimuli. Discussion: These results highlight the role of ER in perceptual biases and offer avenues for future ER-based treatments for specific phobias. [ABSTRACT FROM AUTHOR]

The formation of extraembryonic membranes (EEMs) contributes to the proper development of many animals. In arthropods, the formation and function of EEMs have been studied best in insects. Regarding the development of extraembryonic tissue in chelicerates (spiders and relatives), most information is available for spiders (Araneae). Especially two populations of cells have been considered to represent EEMs in spiders. The first of these potential EEMs develops shortly after egg deposition, opposite to a radially symmetrical germ disc that forms in one hemisphere of the egg and encloses the yolk. The second tissue, which has been described as being extraembryonic is the so-called dorsal field, which is required to cover the dorsal part of the developing spider germ rudiment before proper dorsal closure. In this review, we summarize the current knowledge regarding the formation of potential extraembryonic structures in the Chelicerata. We describe the early embryogenesis of spiders and other chelicerates, with a special focus on the formation of the potential extraembryonic tissues. This article is part of the theme issue 'Extraembryonic tissues: exploring concepts, definitions and functions across the animal kingdom'. [ABSTRACT FROM AUTHOR]

In the present study we describe and discuss for the first time the peculiar myrmecophilous habits of Anagraphis ochracea (L. Koch, 1867) and its strong association with the ant species Messor ibericus Santschi, 1931. The study is based on behavioural observations carried out both in the field and in captivity, and sheds light on the lifestyle of this poorly studied and rarely observed species. We also record the presence of A. ochracea on continental Italy and Sicily for the first time, provide a brief overview of its taxonomic history and present photographs of adult and juvenile specimens, the egg sac and the copulatory organs of both sexes. Finally, we provide a DNA-barcode (COI) for A. ochracea, which is the first for the genus Anagraphis as well. [ABSTRACT FROM AUTHOR]

Two female Philodromus specimens were found with genital structures similar to those described for Philodromus depriesteri Braun, 1965, currently considered a nomen dubium. Molecular analysis revealed that the two specimens belong to the species Philodromus collinus C. L. Koch, 1835. The opisthosomas of both spiders each contained a parasitoid, and one of the worms was identified as a member of the nematode family Mermithidae. It is very likely that the parasitoids interfered with the development of the female genital organs, resulting in the characteristic depriesteri vulva structure. Consequently, we propose Philodromus depriesteri Braun, 1965 = Philodromus collinus C. L. Koch, 1835 syn. nov., thus releasing P. depriesteri from being considered a nomen dubium. [ABSTRACT FROM AUTHOR]

Parasitoids are significant ecological elements of terrestrial food webs and have evolved within seven insect orders. Interestingly, however, associations with spiders as hosts have evolved only in two insect orders, Diptera and Hymenoptera. Here, we summarize various aspects of host utilization by dipteran flies with an emphasis on associations with spiders. Our synthesis reveals that spider flies (family Acroceridae) have evolved a unique life strategy among all the parasitoid taxa associated with spiders, in which koinobiont small-headed flies utilize an indirect oviposition strategy. This indirect oviposition in spider flies is inherited from Nemestrinimorpha ancestors which appeared in the Late Triassic and is characterized by the evolution of planidial larvae. Further, we discuss the advantages and disadvantages of indirect oviposition in spider flies. On the one hand, indirect oviposition allows the fly to avoid contact/wrestling with spider hosts. On the other hand, larval survival is low because the planidium must actively seek out and infect a suitable host individually. The risk of failure to find a suitable spider host is offset by the fly's extremely high fecundity. [ABSTRACT FROM AUTHOR]

Spiders have emerged as one of the leading model organisms in many research fields due to their compelling biology. Often, scientific investigations involving the use of spiders face inevitable problems associated with the lack of specimens from laboratory stock, resulting in difficulties in yielding reproducible investigations for predictive research. Thus, several species of well-studied spiders, including Parasteatoda tepidariorum, have been successfully bred for such purposes. Crossopriza lyoni is a Haplogyne spider, globally distributed and widespread in human inhabitants, prompting interest in various studies over the last decades. Despite its scientific importance, no laboratory-bred C. lyoni has been documented. Therefore, we describe a successful captive breeding system of the species under controlled conditions to establish a laboratory stock culture. Methods for mating induction, egg collection and segregation, artificial embryo incubation, and colony husbandry are discussed. The technique presented is a simple and low-cost approach that is reliable for C. lyoni propagation in the laboratory over several generations. [ABSTRACT FROM AUTHOR]

Predator-prey interactions are the interspecific relationships of greatest interest in ecology. Spiders are among the most diverse and ubiquitous terrestrial predators on the planet. Their large dietary breadth is often linked with the development of specific predatory behaviors and morphological adaptations. However, studies on the predatory behavior of spiders have mostly focused on specialist species, leaving behind the ethological variability occurring in generalist species that allow them to respond to the different prey types. For three species of generalist wandering spiders, we searched images of predation events on the Internet to determine the most common prey. Subsequently, the focal predator species were then used in behavioral experiments. Using high-speed videos, handling patterns for different prey types (spider and cricket) were analyzed. Our results show a notable difference in handling patterns between prey types. We found that the spider prey was often rotated around the axis allowing the predator to bite in the ventral region of the prey and thus avoid a counterattack. Contrary, crickets were arbitrarily rotated. Our work may be an indication that these three species of generalist spiders have a preference for manipulating prey differently with a preference to rotate spiders, allowing them to exploit prey with various defensive mechanisms. • Bite Location: we observed a preference for ventral biting spider prey in the field, online and in the laboratory. • Prey Manipulation: Spider prey is rapidly but non-stereotypically manipulated for a ventral bite, crickets for a dorsal bite. • Unique Behavioral Units: Phoneutria depilata and Trechalea sp. have exclusive behavioral units. • Maximal Velocity and Spider Size: maximum velocity in all three wandering spider species depends on spider size. [ABSTRACT FROM AUTHOR]