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Motion and camouflage were previously considered to be mutually exclusive, as sudden movements can be easily detected. Background matching, for instance, is a well-known, effective camouflage strategy where the colour and pattern of a stationary animal match its surrounding background. However, background matching may lose its efficacy when the animal moves, as the boundaries of the animal become more defined against its background. Recent evidence shows otherwise, as camouflaged objects can be less detectable than uncamouflaged objects even while in motion. Here, we explored whether the detectability of computer-generated stimuli varies with the speed of motion, background (matching and unmatching) and size of stimuli in six species of jumping spiders (Araneae: Salticidae). Our results showed that, in general, the responsiveness of all six salticid species tested decreased with increasing stimulus speed regardless of whether the stimuli were conspicuous or camouflaged. Importantly, salticid responses to camouflaged stimuli were significantly lower compared with those to conspicuous stimuli. There were significant differences in motion detectability across species when the stimuli were conspicuous, suggesting differences in visual acuity in closely related species of jumping spiders. Furthermore, small stimuli elicited significantly lower responses than large stimuli across species and speeds. Our results thus suggest that background matching is effective even when stimuli are in motion, reducing the detectability of moving stimuli., Competing Interests: Competing interests The authors declare no competing or financial interests., (© 2024. Published by The Company of Biologists Ltd.)

Predator functional responses describe predator feeding rates and are central to predator-prey theory. Originally defined as the relationship between predator feeding rates and prey densities, it is now well known that functional responses are shaped by a multitude of factors. However, much of our knowledge about how these factors influence functional responses is based on laboratory studies that are generally logistically constrained to examining only a few factors simultaneously and that have unclear links to the conditions organisms experience in the field. We apply an observational approach for measuring functional responses to understand how sex/stage differences, temperature and predator densities interact to influence the functional response of zebra jumping spiders on midges under natural conditions. We used field surveys of jumping spiders to infer their feeding rates and examine the relationships between feeding rates, sex/stage, midge density, predator density and temperature using generalized additive models. We then used the relationships supported by the models to fit parametric functional responses to the data. We find that feeding rates of zebra jumping spiders follow some expectations from previous laboratory studies such as increasing feeding rates with body size and decreasing feeding rates with predator densities. However, in contrast to previous results, our results also show a lack of temperature response in spider feeding rates and differential decreases in the feeding rates of females and juveniles with densities of different spider sexes/stages. Our results illustrate the multidimensional nature of functional responses in natural settings and reveal how factors influencing functional responses can interact with one another through behaviour and morphology. Further studies investigating the influence of multiple mechanisms on predator functional responses under field conditions will increase our understanding of the drivers of predator-prey interaction strengths and their consequences for communities and ecosystems., (© 2022 The Authors. Journal of Animal Ecology published by John Wiley & Sons Ltd on behalf of British Ecological Society.)

Predator functional responses describe predator feeding rates and are central to predator-prey theory. Ecologists have measured thousands of predator functional responses using the same basic experimental method. However, this design is ill-suited to address many current questions regarding functional responses. We derive a new experimental design and statistical analysis that quantifies functional responses using the times between a predators' feeding events requiring only one or a few trials. We examine the feasibility of the experimental method and analysis using simulations to assess the ability of the statistical model to estimate functional response parameters and perform a proof-of-concept experiment estimating the functional responses of two individual jumping spiders. Our simulations show that the statistical method reliably estimates functional response parameters. Our proof-of-concept experiment illustrates that the method provides reasonable estimates of functional response parameters. By virtue of the fewer number of trials required to measure a functional response, the method derived here promises to expand the questions that can be addressed using functional response experiments and the systems in which they can be measured. Thus, we hope that our method will refine our understanding of functional responses and predator-prey interactions more generally., (© 2021 by the Ecological Society of America.)

Many spiders and insects can perform rapid jumps from smooth plant surfaces. Here, we investigate how jumping spiders (Pseudeuophrys lanigera and Sitticus pubescens) avoid slipping when accelerating. Both species differed in the relative contribution of leg pairs to the jump. P. lanigera accelerated mainly with their long third legs, whereas their short fourth legs detached earlier. In contrast, S. pubescens accelerated mainly with their long fourth legs, and their short third legs detached earlier. Because of the different orientation (fourth-leg tip pointing backward, third-leg tip pointing forward), the fourth-leg tarsus pushed, whereas the third-leg tarsus pulled. High-speed video recordings showed that pushing and pulling was achieved by different attachment structures. In P. lanigera, third-leg feet made surface contact with setae on their distal or lateral claw tuft, whereas fourth-leg feet engaged the proximal claw tuft, and the distal tuft was raised off the ground. S. pubescens showed the same division of labour between proximal and distal claw tuft for pushing and pulling, but the claw tuft contact lasted longer and was more visible in the fourth than in the third legs. Experimental ablation of claw tufts caused accelerating spiders to slip, confirming that adhesion is essential for jumps from smooth substrates.

Background: Habronattus is a diverse clade of jumping spiders with complex courtship displays and repeated evolution of Y chromosomes. A well-resolved species phylogeny would provide an important framework to study these traits, but has not yet been achieved, in part because the few genes available in past studies gave conflicting signals. Such discordant gene trees could be the result of incomplete lineage sorting (ILS) in recently diverged parts of the phylogeny, but there are indications that introgression could be a source of conflict., Results: To infer Habronattus phylogeny and investigate the cause of gene tree discordance, we assembled transcriptomes for 34 Habronattus species and 2 outgroups. The concatenated 2.41 Mb of nuclear data (1877 loci) resolved phylogeny by Maximum Likelihood (ML) with high bootstrap support (95-100%) at most nodes, with some uncertainty surrounding the relationships of H. icenoglei, H. cambridgei, H. oregonensis, and Pellenes canadensis. Species tree analyses by ASTRAL and SVDQuartets gave almost completely congruent results. Several nodes in the ML phylogeny from 12.33 kb of mitochondrial data are incongruent with the nuclear phylogeny and indicate possible mitochondrial introgression: the internal relationships of the americanus and the coecatus groups, the relationship between the altanus, decorus, banksi, and americanus group, and between H. clypeatus and the coecatus group. To determine the relative contributions of ILS and introgression, we analyzed gene tree discordance for nuclear loci longer than 1 kb using Bayesian Concordance Analysis (BCA) for the americanus group (679 loci) and the VCCR clade (viridipes/clypeatus/coecatus/roberti groups) (517 loci) and found signals of introgression in both. Finally, we tested specifically for introgression in the concatenated nuclear matrix with Patterson's D statistics and D FOIL . We found nuclear introgression resulting in substantial admixture between americanus group species, between H. roberti and the clypeatus group, and between the clypeatus and coecatus groups., Conclusions: Our results indicate that the phylogenetic history of Habronattus is predominantly a diverging tree, but that hybridization may have been common between phylogenetically distant species, especially in subgroups with complex courtship displays.

Many spiders from the salticid subfamily Spartaeinae specialize at preying on other spiders and they adopt complex strategies when targeting these dangerous prey. We tested 15 of these spider-eating spartaeine species for the capacity to plan detours ahead of time. Each trial began with the test subject on top of a tower from which it could view two boxes: one containing prey and the other not containing prey. The distance between the tower and the boxes was too far to reach by leaping and the tower sat on a platform surrounded by water. As the species studied are known to avoid water, the only way they could reach the prey without getting wet was by taking one of two circuitous walkways from the platform: one leading to the prey ('correct') and one not leading to the prey ('incorrect'). After leaving the tower, the test subject could not see the prey and sometimes it had to walk past the incorrect walkway before reaching the correct walkway. Yet all 15 species chose the correct walkway significantly more often than the incorrect walkway. We propose that these findings exemplify genuine cognition based on representation., (© 2016 Society for the Experimental Analysis of Behavior.)

Salticids are diurnal hunters known for acute vision, remarkable predatory strategies and jumping ability. Like other jumpers, they strive for stability and smooth landings. Instead of using inertia from swinging appendages or aerodynamic forces by flapping wings as in other organisms, we show that salticids use a different mechanism for in-air stability by using dragline silk, which was previously believed to function solely as a safety line. Analyses from high-speed images of jumps by the salticid Hasarius adansoni demonstrate that despite being subject to rearward pitch at take-off, spiders with dragline silk can change body orientation in the air. Instantaneous drag and silk forces calculated from kinematic data further suggest a comparable contribution to deceleration and energy dissipation, and reveal that adjustments by the spider to the silk force can reverse its body pitch for a predictable and optimal landing. Without silk, upright-landing spiders would slip or even tumble, deferring completion of landing. Thus, for salticids, dragline silk is critical for dynamic stability and prey-capture efficiency. The dynamic functioning of dragline silk revealed in this study can advance the understanding of silk's physiological control over material properties and its significance to spider ecology and evolution, and also provide inspiration for future manoeuvrable robot designs.

The Laufeia clade is a peculiar lineage of euophryine jumping spiders showing rapid divergence of male genital structures, especially the embolic complex that directly interacts with female genitalia during sperm transfer. With the rapid growth of species discovery and the perplexing morphology of male genitalia in the Laufeia clade, the controversy in its classification has become a crucial problem. In this study, we applied a phylogenomic approach using ultra‐conserved elements data to infer the phylogeny of the Laufeia clade with extensive taxon sampling. A comparative morphological study was performed to evaluate diagnostic characters and understand the evolution of the male embolic complex within the Laufeia clade. The evolution of microhabitats (foliage, tree trunk, rock and surface litter) was also investigated to uncover the potential link between the microhabitat shifts and male embolic complex divergence. The results provide a strongly supported phylogenetic framework and updated generic concepts for the Laufeia clade. The synapomorphies for the updated genera within the Laufeia clade were identified through character mapping on the phylogeny. Ancestral state reconstruction analyses revealed that the Type I embolic complex (characterized by a disc‐like embolic disc with a lamina as its outer edge) was ancestral and gradually evolved into the Type II (without lamina of embolic disc, base of embolic complex often modified into a functional "conductor") and Type III (lacking lamina of embolic disc and base of embolic complex) embolic complex, and that some embolic shapes evolved multiple times independently in different lineages of the Laufeia clade. The shift from foliage‐dwelling to tree trunk‐dwelling in the common ancestor of the Laufeia clade may have facilitated the divergent evolution of male embolic complex in the Laufeia clade. This study provides a solid foundation for future studies of systematics and evolution of this group. [ABSTRACT FROM AUTHOR]

In many animals, early-life decisions influence long-term fitness. Mantidflies are spider egg predators; their tiny larvae climb aboard spiders to find eggs, but little is known about how they find spiders. We tested the hypothesis that mantidfly larvae (Dicromantispa sayi) detect and respond to substrate-borne spider cues (e.g., silk and/or excreta). We presented larvae with filter paper exposed to different types of spiders (adult female, adult male, or juvenile Habronattus trimaculatus jumping spiders) versus a no-cue control. Larvae spent more time on filter paper with spider cues. We then tested the hypothesis that mantidflies make finer distinctions between spiders when given direct choices between these cues. Larvae did not discriminate between sexes but spent more time (and exhibited more phoretic behavior) on filter paper with female or male cues compared with juvenile cues. While this suggests that mantidflies actively seek out adult spiders, we also found that adult spiders were more active than juveniles and may have simply deposited more silk and excreta, providing a stronger cue to detect. We discuss these findings in the context of the risks and benefits of different spider hosts, and how early-life spider-searching strategies may shape a mantidfly's long-term fitness. [ABSTRACT FROM AUTHOR]

The female of Uroballus nazirwanii Prajapati, Malamel & Sebastian, 2020, is described for the first time, from the Western Ghats region, Kerala, India. Detailed morphological descriptions, diagnostic features, and illustrations of the copulatory organs of both sexes are provided. The current distribution of the genus in India is also mapped. [ABSTRACT FROM AUTHOR]

An annotated checklist and taxonomic review of the spiders of Saint Helena is presented. A total of 88 genera and 114 species are known; of these, 12 genera and 45 species are endemic. Two new genera and two new species are described: Anapistula martinae Sherwood, Harvey, Fowler, Joshua, Stevens, Scipio-O'Dean & Ellick sp. nov., Helenidion Sherwood, Marusik, Fowler, Stevens & Joshua gen. nov., Ischnothyreus christyjoae Sherwood, Henrard, Peters, Stevens & Fowler sp. nov., and Trust Sherwood, Marusik, Wilkins, P. Ashmole & M. Ashmole gen. nov. Three new combinations are proposed: Helenidion sciaphilum (Benoit, 1977) comb. nov. (type species), Helenidion huberti (Benoit, 1977) comb. nov., and Zelotes funereus (Dalmas, 1921) comb. nov.Lepthyphantes albimaculatus (O. Pickard-Cambridge, 1873) (Linyphiidae) is synonymized with Lepthyphantes leprosus (Ohlert, 1865) syn. nov.Lynxosa Roewer, 1960gen. rest. is restored to house the lycosids L. inexorabilis (O. Pickard-Cambridge, 1870) comb. rest., L. ligata (O. Pickard-Cambridge, 1870) comb. rest., L. nefasta (Tongiorgi, 1977) comb. nov., and L. veseyensis (Sherwood, Henrard, Logunov & Fowler, 2023) comb. nov. The previously undescribed sexes of Benoitodes sanctaehelenae (Strand, 1909) (Gnaphosidae), Hahnia laticeps Simon, 1898 (Hahniidae), Helenactyna crucifera (O. Pickard-Cambridge, 1873) (Dictynidae, first known male for the genus), Paraheliophanus napoleonClark & Benoit, 1977 (Salticidae), and Trust solium (Benoit, 1977) comb. nov. (Theridiidae) are described. Bonapruncinia sanctaehelenae Benoit, 1977, originally described from juveniles, is supplemented with a first description of the adult female. Lectotypes and paralectotypes are designated for the salticid species Paraheliophanus subinstructus (O. Pickard-Cambridge, 1873) and Pellenes inexcultus (O. Pickard-Cambridge, 1873). Seven species are newly recorded from the island: Clubiona hitchinsiSaaristo, 2002 (Clubionidae), Latrodectus renivulvatus Dahl, 1902 (Theridiidae), Micropholcus fauroti (Simon, 1887) (Pholcidae), Oecobius marathaus Tikader, 1962 (Oecobiidae), Steatoda nobilis (Thorell, 1875) (Theridiidae), Theridion melanostictum O. Pickard-Cambridge, 1876 (Theridiidae), and Theridion proximum Lawrence, 1964 (Theridiidae). Epigynal duplication, a rare anomaly in spiders, is reported for the prodidomid Zimirina relegataCooke, 1977. [ABSTRACT FROM AUTHOR]

A new species of the lyrate curtain-web spider genus Trechona C. L. Koch, 1850, Trechona minuana sp. nov., is described, based on males and females from Santa Catarina state, South Brazil. It is the first species of the genus from this Brazilian region. Additionally, we describe for the first time the female of Trechona excursoraPedroso, Miranda & Baptista, 2019 based on specimens from its type localities. [ABSTRACT FROM AUTHOR]

A new jumping spider species belonging to the genus OkinawiciusPrószyński, 2016 is described from India: O. tekdi Tripathi & Kulkarni sp. n. (♂♀), collected from the Deccan Plateau in Maharashtra, India. Detailed morphological descriptions and illustrations of the male palp and female genitalia are presented. [ABSTRACT FROM AUTHOR]

A new species of NeonellaGertsch, 1936 is described from Uruguay: N. almitan. sp., which inhabits natural grasslands. Additionally, first records of N. acostae Rubio, Argañaraz & Gleiser, 2015, and new records of N. lubrica Galiano, 1988, N. minutaGaliano, 1965, and N. montana Galiano, 1988 are given. Illustrations of the habitus, sexual characters, photographs of living specimens, natural history data and a distribution map of species of Neonella from Uruguay are provided. Conservation issues based on distributional patterns of the species are proposed. [ABSTRACT FROM AUTHOR]

The jumping spider Marpissa marina (Goyen, 1892) is endemic to Aotearoa New Zealand. In this paper, we redescribe the species. Marpissa marina was placed in the Northern Hemisphere genus Marpissa due to its subjective similarity to spiders in that genus. The original description lacked modern morphological diagnoses and useful illustrations. The description was based largely on the female, and therefore lacked the taxonomically important characters seen in the male pedipalp. Previous literature has suggested M. marina may be related to the Australian genus, Maratus Karsch, 1878. We applied an integrative taxonomic approach based on diagnostic morphological characters and molecular analysis for a more detailed species description and assignment into an appropriate genus. Morphological features indicate that M. marina belongs to Maratus. This is supported by phylogenetic analyses using DNA sequences from the nuclear gene Actin 5C and the mitochondrial gene 16S ribosomal RNA. We transfer Marpissa marina into the genus Maratus, as Maratus marinus (Goyen, 1892), new combination. [ABSTRACT FROM AUTHOR]

A new species of the jumping spider genus Carrhotus Thorell - Carrhotus piperus sp. nov. - is described based on the male holotype collected from Tamil Nadu, India. Detailed description and illustrations are provided. The new species can be separated from the closely related taxa by the prolateral protrusion of the bulb arising from an 8 o'clock position and directed dorsad, and the retrolaterally directed beak-shaped embolus. The number of known Carrhotus species reaches to 10 and 37 in India and in the world, respectively. A key to species of the genus Carrhotus from India is also presented. [ABSTRACT FROM AUTHOR]

The jumping spider species Gedea pinguis Cao & Li, 2016 is newly recorded from Vietnam and redescribed based on the sole male specimen. A detailed redescription, illustrations of the copulatory organs, and somatic features, along with an updated distribution map are provided. DNA barcode derived from the mitochondrial cytochrome c oxidase subunit I (COI) gene of the species G. pinguis from Vietnam is also included for future use and to compare the genetic distances with Gedea cf. tibialis Zabka, 1985 from Malaysia. With the addition of a new record, the genus Gedea Simon, 1902 in Vietnam now reaches 3 species, but doubts arise regarding the conspecificity of the two opposite sex species, Gedea tibialis Żabka, 1985 (male) and Gedea typica (Żabka, 1985) (female), as they share the same type locality. Additionally, a dichotomous key to all Gedea species is also given in this study. [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]

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]

In this paper the findings of a global literature and social media survey of spider mycoses are presented. Our survey revealed that spider mycoses occur in the geographic belt between latitude 78°N and 52°S, and that more than 40 out of the known 135 spider families (ca. 30%) are attacked by fungal pathogens. Jumping spiders (Salticidae), cellar spiders (Pholcidae), and sheet-web spiders (Linyphiidae) are the families most frequently reported to be attacked by fungal pathogens (combined >40% of all reported cases). Ninety-two percent of the infections of spiders can be attributed to pathogens in the order Hypocreales (phylum Ascomycota), and almost exclusively the families Cordycipitaceae and Ophiocordycipitaceae. Within the Hypocreales, the asexually reproductive genus Gibellula is an historically species-rich and widespread genus of specific spider-pathogenic fungi. For ca. 70 species of spider-pathogenic fungi their hosts could be identified at least to family level. The data presented here reaffirm the findings of previous studies that spider-pathogenic fungi are most common and widespread in tropical and subtropical forested areas, with free-living cursorial hunters – dominated by Salticidae – being the most frequently infected. Cursorial hunters (especially Salticidae) and subterranean cellar spiders (Pholcidae) are the most frequently fungus-infected spiders in North America, whereas web-weavers (especially Linyphiidae and Pholcidae) are the most common spider hosts in Europe. Our survey implies that spider-pathogenic fungi are an important mortality factor for spiders which has hitherto been underestimated. [ABSTRACT FROM AUTHOR]

Cold temperatures can cause injury and death, and thermal tolerance influences organismal abundance, distribution, and physiology. We characterized cold tolerance and supercooling point (SCP) in the broadly distributed jumping spider Phidippus audax (Hentz, 1845). We found that P. audax is freeze-avoidant, surviving chilling but not freezing. Freeze-avoidant organisms can reduce harm by lowering their supercooling point (SCP), the temperature at which they freeze. We assayed fall/winter SCP in field-acclimated spiders from Michigan and compared lab-acclimated spiders from Texas, Oklahoma, and Michigan. Field-acclimated Michigan spiders decreased their SCP from –4.7 °C in September to –12.9 °C in November. In the lab, Michigan spiders had the lowest SCP (–7.65 °C) followed by Oklahoma (–6.21 °C) and Texas (–5.50 °C). In December and January, nearly all the spiders from Texas and Oklahoma died in the simulated freezing conditions while the Michigan spiders survived at high rates, further suggesting that the Michigan spiders were hardiest followed by Oklahoma and Texas. The lab-acclimated spiders did not consistently reduce their SCP from October to December. Smaller spiders had lower SCPs than larger spiders, and the Michigan spiders were significantly smaller than those from Texas or Oklahoma, suggesting that smaller overwintering size or delayed molting to mature size/sexual maturity may be favored by selection in colder climates. This could help explain differences in size and life cycle between northern and southern P. audax, as well as a previously described trend for smaller spiders to be more common in colder areas or Europe. [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]

Two ant-mimicking jumping spider species of the genus Myrmarachne MacLeay, 1839 (Araneae: Salticidae): Myrmarachne melanocephala and M. kiboschensis are recorded from Manipur, India. Ecologically, M. melanocephala are dominant as compared to M. kiboschensis and ecological niche seems to overlap in many cases. In the present study, the males and females of these species are re-described through morphometric data and their copulatory organ structures. [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]

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]

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]

Habitat fragmentation is among the greatest threats to arachnids present in the forests, especially to Enoploctenus cyclothorax (Ctenidae), which is widely distributed in the Atlantic Forest of southern and southeastern Brazil. Fragmented populations, whether due to anthropic or stochastic factors, tend to be more susceptible to extinction, since genetic diversity is reduced in small and isolated populations. Considering this, the current work aimed to understand how the genetic variability is distributed in six populations of E. cyclothorax (120 individuals sampled), sampled in fragments of the Atlantic Forest in Paraná (Brazil), based on Single Nucleotide Polymorphism (SNP) genotyping. The results obtained support the separation of E. cyclothorax into two distinct genetic groups in the state, based mainly on analyses of genetic structure and connectivity. A strong and significant genetic structure was observed in the species, supported by the k = 3 estimated using Bayesian analysis, by the high values of FST genetic differentiation, and by the low gene flow identified between the genetic groups. Corroborating these results, isolation by distance and the presence of a genetic barrier in the evaluated populations were evidenced. Population genomic analysis also revealed non-homogeneous genetic diversity in E. cyclothorax (HE = 0.14 to 0.31). The hypothesis that population fragmentation could possibly impact the genetic variability of E. cyclothorax throughout the state was confirmed by the inferred data, which point to phytophysiognomy, geographical distance, and forest fragmentation as factors that shaped the current genetic structure identified in the evaluated populations. [ABSTRACT FROM AUTHOR]

An accurate assessment of species diversity is a cornerstone of biology and conservation. The lynx spiders (Araneae: Oxyopidae) represent one of the most diverse and widespread cursorial spider groups, however their species richness in Asia is highly underestimated. In this study, we revised species diversity with extensive taxon sampling in Taiwan and explored species boundaries based on morphological traits and genetic data using a two-step approach of molecular species delimitation. Firstly, we employed a single COI dataset and applied two genetic distance-based methods: ABGD and ASAP, and two topology-based methods: GMYC and bPTP. Secondly, we further analyzed the lineages that were not consistently delimited, and incorporated H3 to the dataset for a coalescent-based analysis using BPP. A total of eight morphological species were recognized, including five new species, Hamataliwa cordivulvasp. nov., Hamat. leporaurissp. nov., Tapponia auriolasp. nov., T. parvasp. nov. and T. rarobulbussp. nov., and three newly recorded species, Hamadruas hieroglyphica (Thorell, 1887), Hamat. foveata Tang & Li, 2012 and Peucetia latikae Tikader, 1970. All eight morphological species exhibited reciprocally monophyletic lineages. The results of molecular-based delimitation analyses suggested a variety of species hypotheses that did not fully correspond to the eight morphological species. We found that Hamat. cordivulvasp. nov. and Hamat. foveata showed shallow genetic differentiation in the COI, but they were unequivocally distinguishable according to their genitalia. In contrast, T. parvasp. nov. represented a deep divergent lineage, while differences of genitalia were not detected. This study highlights the need to comprehensively employ multiple evidence and methods to delineate species boundaries and the values of diagnostic morphological characters for taxonomic studies in lynx spiders. [ABSTRACT FROM AUTHOR]

Large‐scale barcoding projects help to aggregate information on genetic variability of multiple species throughout their ranges. Comparing DNA sequences of both non‐conspecific and conspecific individuals from distant parts of their ranges helps to compare level of genetic isolation‐by‐distance patterns in different species and adaptive types. We compared mitochondrial CO1 gene sequences of 223 spiders from Georgia (Caucasus), representing 124 species and eight families, with 3097 homological sequences from spiders mostly from Europe, but also from other parts of the World. In most families, a significant isolation‐by distance pattern was observed on family level. On species level, a significant isolation‐by‐distance was observed in 40 species, although this low proportion is most likely related to a lack of data. Simultaneously, remarkable differences in spatial structure were shown for different species. Although the majority of the studied species have a broad western Palearctic range, web‐building spiders from families Araneidae, Theridiidae, and Linyphiidae are less isolated spatially than flower spiders (Thomisidae), jumping spiders (Salticidae), wolf spiders (Lycosidae), sac spiders (Clubionidae), and ground spiders (Gnaphosidae). This pattern is related with more common ballooning in web building than in actively hunting spiders, which commonly remain isolated since preglacial time. Ground spiders build the most isolated populations in the Caucasus. [ABSTRACT FROM AUTHOR]

A recurrent question in animal contests is whether individuals adopt a self or mutual assessment rule to decide to withdraw from a contest. However, many empirical studies fail to find conclusive support for one of these two possibilities. A possible explanation is that assessment strategies vary between individuals. In the contests of the orb-web spider Trichonephila clavipes , males perform a vibrational display on webs that may escalate to physical contact. Since all individuals perform the vibrational phase and only some of them escalate, we proposed 2 hypotheses: (1) all individuals perform mutual assessment during the vibrational phase, or (2) some individuals that do not escalate adopt self-assessment, while individuals that escalated adopt mutual assessment. To evaluate these hypotheses, we investigated the relationship between the duration of the vibrational phase and frontal leg length (a proxy of male fight capacity) of loser and winner males in contests that escalated and did not escalate to the physical contact phase. We found a non-significant relationship between duration and losers leg length for both contests that escalate and did not escalate. While we found a positive relationship between duration and winners leg length, particularly in contests that did not escalate. These results do not provide support for mutual assessment or for a mix of different assessment rules among individuals. We suggest that in T. clavipes , the dynamics of the vibrational phase may be explained by two different contest strategies (opponent-only assessment or size-based aggressiveness) that are dependent on intruder motivation to escalate. [ABSTRACT FROM AUTHOR]

Five new species of the genus Bifurcia are described: B. kangding sp. nov. (♂♀), B. labahe sp. nov. (♂), B. luding sp. nov. (♂♀), B. shuangqiao sp. nov. (♂♀), and B. xiaojin sp. nov. (♂♀) from western Sichuan, China. A distribution map of the species and illustrations of genital characters are provided in this paper. [ABSTRACT FROM AUTHOR]

Five species of the genus Opopaea Simon, 1892 from southern China are recognised, including four new species: Opopaea mangun Tong & Li, sp. nov., Opopaea taibao Tong & Yang, sp. nov., Opopaea wenshan Tong & Zhang, sp. nov. and Opopaea yuhuang Tong & Li, sp. nov. from Yunnan and one newly-recorded species: Opopaea foveolata Roewer, 1963 from Hainan. Detailed diagnoses, descriptions and photomicroscopy images of new species are provided, based on specimens of both sexes. A key to species of the genus Opopaea from China is provided. [ABSTRACT FROM AUTHOR]

The jumping spider genus Iranattus Prószyński, 1992, distributed from Africa to southwestern Asia, has been placed within the Harmochirina because of their male palp structures and elongated third legs. Here, we present phylogenomic evidence that it belongs instead to the subtribe Plexippina, further supported by the presence of two coupling pockets in the female epigyne. In this study, we redescribe I. principalis (Wesołowska, 2000) and I. rectangularis Prószyński, 1992. Additionally, the female of I. rectangularis, the type species of the genus, is described for the first time, and we report its range extension east to India. [ABSTRACT FROM AUTHOR]

This paper provides the re-description of Epeus albus Prószynski, 1992, with the first description of its male. Additionally, Epeus chilapataensis (Biswas & Biswas, 1992) is synonymised with E. albus and a new taxonomic combination is proposed: Epeus khandalaensis (Tikader, 1977) comb. nov. (ex Phidippus). Clarification on the record of Epeus daiqini Patoleta, Gardzińska & Żabka, 2020 from India is provided. The current distribution of the genus in India is also mapped. [ABSTRACT FROM AUTHOR]

Three new species of the genera Thiania C. L. Koch, 1846 and Yaginumaella Prószyński, 1979 are described and named as T. bamian sp. nov. (♂♀), T. flacata sp. nov. (♀) and Y. curvata sp. nov. (♂♀), from Hunan Province, China. Detailed descriptions, photos of somatic features and copulatory organs, as well as a distribution map are provided. Nucleotide data for the barcoding gene, cytochrome c oxidase subunit I (COI) of T. bamian sp. nov. (♂♀) and Y. curvata sp. nov. (♀) are provided. [ABSTRACT FROM AUTHOR]

Aim: To assess the relative relevance of dispersal limitation and species sorting as drivers of spatial turnover between spider faunas of European territories. Location: Continental Europe. Time period: Present. Major taxa studied: Spiders (Order Araneae). Methods: We analysed how distance‐decay patterns differ between northern and southern Europe (broadly, territories covered vs. not covered by ice sheets during the last glacial maximum, respectively) in 15 spider families, using standardized distances to allow a direct comparison between parameters (i.e. slope and intercept) of climatic and spatial distance‐decay models. Thus, we assessed North–South differences in parameters of spatial and, independently, climatic distance‐decay models, and whether those differences are explained by family‐specific traits related to dispersal ability. Results: Climatic and spatial distance‐decay patterns are very similar in northern Europe, where climatic and spatial distances are highly correlated. In contrast, slopes are steeper in spatial than in climatic distance‐decay curves in southern Europe, where climatic and spatial distances are decoupled. Moreover, family traits related to dispersal ability explained the North–South difference in spatial distance‐decay slopes, as well as the amount of nestedness‐resultant dissimilarity between southern and northern spider faunas. Main conclusions: Our results suggest that differences in beta diversity patterns between northern and southern Europe reflect the strength of dispersal limitation in spiders, which varies across families and leads to different degrees of disequilibrium with current climatic conditions depending on the taxon. Moreover, in the South of Europe, where spatial and climatic distances are uncorrelated, spatial distance‐decay models are steeper and have larger explanatory power than climatic distance‐decay models, which suggests that dispersal limitation is the main factor shaping current beta diversity patterns of European spiders at the continental scale. [ABSTRACT FROM AUTHOR]

The genus KirinuaLi & Lin, 2021 belonging to the family Symphytognathidae was established based on the type species, Kirinua maguaiLi & Lin, 2021. A total of three cavedwelling Kirinua species were recorded from Guangxi, China. In this paper, another new troglobitic spider species from the limestone Jinlong Cave in southern China is described under the name Kirinua jinlong sp. nov. Detailed descriptions, illustrations, and diagnosis are given to this new species, as well as a distribution map for all known species of the genus Kirinua. [ABSTRACT FROM AUTHOR]

Salticidae is the largest family of spiders in terms of described species. Chira Peckham & Peckham, 1896 is a genus with a Neotropical distribution, with 13 described species, but only six have both sexes known. Among the described species, 10 occur in Brazil, including Chira simoni Galiano, 1961 that has only the male described. The main objective of this work is to redescribe Chira simoni, 1961 and describe the female for the first time. The species Chira distincta Bauab-Vianna, 1983 is synonymized with Chira spinosa (Mello-Leitão, 1939), syn. nov. and Chira reticulata (Mello-Leitão, 1943) is synonymized with Chira thysbe Simon, 1902, syn. nov. A discussion about the groups of Chira species is presented, as well as new diagnoses and an update on the distribution of the genus Chira in the Neotropical region. [ABSTRACT FROM AUTHOR]

This article, published in the Journal of Threatened Taxa, discusses the discovery of two previously undocumented species of jumping spiders in Gujarat, India. The species, Stenaelurillus marusiki and Stenaelurillus vyaghri, were identified through recent investigations and are being documented for the first time in Gujarat. The specimens were collected and studied using a stereomicroscope and digital camera, and their characteristics were compared to existing literature. The article provides detailed descriptions and images of the spiders, as well as information about their distribution in India. [Extracted from the article]

With 252 species, Pseudopoda Jäger, 2000, is the largest genus in the family Sparassidae and is widely distributed in South (49 species in Bhutan, India, Nepal and Pakistan), East (158 species in China and Japan) and Southeast Asia (51 species in Indonesia, Laos, Myanmar, Thailand and Vietnam). Few species have been found in more than one region. In this paper, three new species of Pseudopoda are described from East and Southeast Asia. Among them, one from China: P. fengtongzhaiensis Jäger & Liu, sp. nov. (♀); one from Laos: P. baimai Jäger & Liu, sp. nov. (♀); and one from Thailand: P. inthanonensis Jäger & Liu, sp. nov. (♀). Additionally, the female of P. kavanaughi Zhang, Jäger & Liu, 2023 is described for the first time. Photos of the habitus and genitalia, as well as a distribution map of all four species, are provided. [ABSTRACT FROM AUTHOR]