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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]

ABSTRACT Pre‐copulatory sexual cannibalism is an extreme form of aggression toward potential mates. In this study, we examined condition‐dependent female aggression and its effects on mating success and frequency of pre‐copulatory sexual cannibalism in the jumping spider Phidippus audax Hentz 1845. We examined two of the leading hypotheses of why sexual cannibalism may occur, (1) female mate choice and (2) adaptive female foraging. We separated 137 adult virgin female P. audax into three feeding treatments: (1) well‐fed spiders, (2) 14‐day food deprived, and (3) 28‐day food deprived. We recorded weight loss (14‐ and 28‐day treatments) and survival rates. We conducted mating trials to measure the proportion of non‐aggressive and aggressive male and female behaviors, male mating success, and pre‐copulatory sexual cannibalism. Females deprived of food had higher weight loss and lower survival rates than well‐fed females. In addition, food deprived female spiders exhibited higher proportions of aggressive behaviors and pre‐copulatory sexual cannibalism, and lower mating success compared to well‐fed spiders. We found that as male size increased females were less likely to cannibalize males, but we found no effect of male body condition on whether a male mated with or was cannibalized by a female. Our results are consistent with the adaptive foraging hypothesis and corroborates prior research on pre‐copulatory sexual cannibalism. [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]

Most organisms are at risk of being consumed by a predator or getting infected by a parasite at some point in their life. Theoretical constructs such as the landscape of fear (perception of risk) and nonconsumptive effects (NCEs, costly responses sans predation or infection) have been proposed to describe and quantify antipredator and antiparasite responses. How prey/host species identify and respond to these risks determines their survival, reproductive success and, ultimately, fitness. Most studies to date have focused on either predator–prey or parasite–host interactions, yet habitats and ecosystems contain both parasitic and/or predatory species that represent a complex and heterogenous mosaic of risk factors. Here, we experimentally investigated the behavioral responses of a cactophilic fruit fly, Drosophila nigrospiracula, exposed to a range of species that include parasites (ectoparasitic mite), predators (jumping spiders), as well as harmless heterospecifics (nonparasitic mites, ants, and weevils). We demonstrate that D. nigrospiracula can differentiate between threat and non‐threat species, increase erratic movements and decrease velocity in the presence of parasites, but decrease erratic movements and time spent grooming in the presence of predators. Of particular importance, flies could distinguish between parasitic female mites and nonparasitic male mites of the same species, and respond accordingly. We also show that the direction of these NCEs differs when exposed to parasitic mites (i.e., risk of infection) versus spiders (i.e., risk of predation). Given the opposing effects of predation versus infection risk on fly behavior, we discuss potential trade‐offs between parasite and predator avoidance behaviors. Our findings illustrate the complexity of risk assessment in a landscape of fear and the fine‐tuned NCEs that arise in response. Moreover, this study is the first to examine these behavioral NCEs in a terrestrial system. [ABSTRACT FROM AUTHOR]

Psecas euoplus Chamberlin & Ivie, 1936 is recorded for the first time from Colombia. In addition, the known distribution of the species Lyssomanes amazonicus G.W. Peckham, E.G. Peckham & Wheeler, 1889, Lyssomanes bitaeniatus G.W. Peckham, E.G. Peckham & Wheeler, 1889, Lyssomanes remotus G.W. Peckham & E.G. Peckham, 1896, and Sarinda armata (G.W. Peckham & E.G. Peckham, 1892), are extended to the department of Córdoba. We provide descriptions of the species reported here as well as images and drawings of both type material and our new records.

A new species of spiders Sibianor caucasicus sp. n. from the Republic of North Ossetia–Alania, Russia (Sunzhenskiy and Zmeyskiy Mt. ranges; elevations 426–1850 m a.s.l.) is diagnosed, illustrated and described based on males and females. The new species is most similar to Sibianor tantulus (Simon, 1868) and S. aemulus (Gertsch, 1934), but can be distinguished from both by the notably shorter embolus (barely extending beyond the apical end of the tegulum) in the males, and the presence of a distinctive 90-degree bend of insemination ducts (but no first loop) in the females. The distribution of species of the genus in the Caucasus is discussed.

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.

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]

Prey animals employ masquerade to avoid recognition by visual predators by developing a resemblance to inedible objects in their environment. Phytophagous flea beetles seem to resemble models of their own manufacture. While feeding they cause light- or dark-coloured hole-like damage on the leaves of their host plants that resembles the beetle's body in colour and size. Resemblance to the model and the frequency of the model can influence the efficiency of masquerade. To examine masquerade efficiency in light- and dark-coloured beetles, we evaluated their survival benefits from resembling feeding damage in the field. This was done by using two species of beetle of different colour as prey and a jumping spider as the predator. Dark-coloured species were more likely to avoid predation when they were placed on a background with damage similar in colour to their body, whereas increased survival was not recorded for light-coloured species. The extent of the feeding damage of 34 light- and dark-coloured species of beetle was compared. Variation in the extent of the damage was associated more with host plant taxa than beetle body colour. These results indicate that the efficiency of masquerade can vary among beetle species and/or phenotypes. [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]

Animal vision depends on opsins, a category of G protein-coupled receptor (GPCR) that achieves light sensitivity by covalent attachment to retinal. Typically binding as an inverse agonist, 11-cis retinal photoisomerizes to the all-trans isomer and activates the receptor, initiating downstream signaling cascades. Retinal bound to bistable opsins isomerizes back to the 11-cis state after absorption of a second photon, inactivating the receptor. Bistable opsins are essential for invertebrate vision and nonvisual light perception across the animal kingdom. While crystal structures are available for bistable opsins in the inactive state, it has proven difficult to form homogeneous populations of activated bistable opsins either via illumination or reconstitution with all-trans retinal. Here, we show that a nonnatural retinal analog, all-trans retinal 6.11 (ATR6.11), can be reconstituted with the invertebrate bistable opsin, Jumping Spider Rhodopsin-1 (JSR1). Biochemical activity assays demonstrate that ATR6.11 functions as a JSR1 agonist. ATR6.11 binding also enables complex formation between JSR1 and signaling partners. Our findings demonstrate the utility of retinal analogs for biophysical characterization of bistable opsins, which will deepen our understanding of light perception in animals. [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 study was conducted to document the nesting behaviour and prey composition of a crabronid wasp, Trypoxylon sp. The wasp was molecularly characterised as T. clavicerum (NCBI Accession No. OQ913679.1). Nest acceptance rate was significantly higher in the reeds of Ipomea carnea (79.20%) and bamboo (84.80%). The mean number of brood cells (4.40 ± 0.89 cells/nest) and vestibular cells (1.06 cells/nest) built by the wasp was significantly higher in the reeds of I. carnea. Brood parasitisation by the nest parasite Amobia sp. was significantly higher in nests built by the wasp in paper straws (58.57%) compared to the nests built in the reeds of bamboo (23.33%). The mean durations of the egg, larval and pupal stages of T. clavicerum were 2.60 ± 0.55, 6.01 ± 0.71 and 4.80 ± 0.84 days. The number of nests recovered was observed to be the highest during the months of August (3.66 ± 1.53 nests), September (5.00 ± 4.36 nests), October (8.67 ± 2.89 nests) and November (6.00 ± 2.10 nests). The major species of spider from the occupied nests belonged to two families, viz. Salticidae (81%) and Oxyopidae (19%). During the nesting period the adult wasp provisioned a greater number of spiderlings (3.25 to 3.60 spiderlings/cell) than adult spiders (1.20 to 1.60 adult spiders/cell) to her brood. The time taken to complete a single nest provisioned with adult spiders and spiderlings (13.20 ± 6.83 hr/single nest) was significantly less than for the nests provisioned with adult spiders (46.80 ± 14.80 hr/single nest) only. This study is the first ever report of nesting behaviour and prey composition of the spider-hunting wasp T. clavicerum from India. [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]

Jumping spiders display some of the richest visually mediated behaviours in nature. Vision is indeed the most important sensory modality in these spiders where motion detection and response to visual stimuli allow key behaviours such as hunting, escaping from predators and mating. These spiders have been used in various experiments demonstrating the existence of good associative learning and memory abilities, whose mechanism parallels that found in vertebrates. Here we focused on the habituation and dishabituation (H/DH) paradigm, indicating either a gradual decrease in responsiveness to repeated visual stimuli (H), or a recovery in response wherein the reaction towards a known stimulus is enhanced (DH). H is an elementary form of nonassociative learning and memory, which is expected to vary from individual to individual. The link between personality and H/DH has been shown in many vertebrates, but rarely in invertebrates. The jumping spider Menemerus semilimbatus was used in our study to address the question of whether boldness is related to H/DH. In our protocol, habituation was assessed by repeatedly presenting a visual stimulus on a screen to spiders tethered on a locomotor compensator. In the same individuals, boldness was assessed in a walking arena equipped with a shelter. We found that M. semilimbatus habituated and dishabituated to our visual stimulus and that they differed along a shy–bold axis. However, contrary to our expectations, boldness was not related to learning. In consideration of these results, we speculate that the nature (neutral value) of the stimulus might have played a role in making learning independent from boldness. • We tested boldness and visual habituation in the spider Menemerus semilimbatus. • Spiders showed consistent boldness type in four behavioural parameters. • They reduced their response to the stimulus due to habituation. • They increased rotational movement in response to the first dishabituation stimulus. • Boldness was not related to habituation or dishabituation. [ABSTRACT FROM AUTHOR]

The practical near impossibility of empirical attempts in estimating optimal controller gains makes the use of metaheuristics strategies inevitable to automatically obtain these gains by an iterative heuristic simulation procedure. The convergence of the gain values to the local or global solutions occur with ease. In designing controllers for the Twin-Rotor MIMO System (TRMS) Jumping Spider Optimization Algorithm (JSOA), a novel neoteric population-based bio-inspired metaheuristic approach is used to obtain optimum values for the Proportional Integral and Derivative (PID) controllers. With the kp, ki, kd controller gains as the decision variables, the JSOA solution to a nonlinear multi-objective optimization problem subject to some intrinsic constraints spawned optimal values for the controllers' variables. Counter to other algorithms (deterministic and stochastic) that get caught in local minima, JSOA evolved a solution after searchingly rummaging the entire solution search space in a vectorized fashion for an optimal value. Compared with several other versatile controllers (using GA, PSO, Pattern Search, and Simulated Annealing), statistical results obtained showed JSOA technique provided a unique solution and found the gains of the PID controllers marginally in relation to the others (optimization methods). [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]

The fauna of spiders which is a significant part of agriculture ecosystem was observed in 8 crop fields during the kharif. The spiders were caught from June-October, using sweep nets. The total numbers of spider species were 37 representing 12 families. Araneidae was the most abundant family, followed by Thomisidae, Salticidae, Oxyopidae, Tetragnathidae, Clubionidae, Dictynidae, Gnaphosidae, Lycosidae, Sparassidae, Theridiidae and Ulboridae. The species diversity index (H`) was 4.98 and the Equitability index (EH) was 0.95. An ordination of correspondence analysis demonstrated a bunching of the spiders commencing to paddy fields was more as compared to other crops. Thus, paddy seemed to give better natural niche for the spiders than other field crops. Increasing use of pesticides is the main menace to the several species and their survival in agroecosystem. [ABSTRACT FROM AUTHOR]

Cytological and chromosomal studies of ant-like spiders Myrmarachne melanocephala MacLeay, 1839, were undertaken with 12 males captured alive in the months of January to July 2023 from three habitats. The haploid count of male specimens was observed to be 13: 4 acrocentric (including X chromosome), 6 subtelocentric, 2 submetacentric, and 1 metacentric and showed X0 sex determination mechanisms, so the diploid count of the species was 25 (13+12). The single sex chromosome occupied roughly 4-6 per cent of the nuclear volume prominently in the Interphase -- Prophase I stage. The structure of X chromosome in interphase stage was circular-rectangular block. The peculiar shape of rod-shaped X chromosome was maintained from early pre-leptotene stage till the end of the division particularly the Prophase I. The synapsis started early from late leptotene and duration of zygotene was long enough to visualize the perfect ones in late zygotene. There were nine diplotene bivalents with interstitial chiasma. [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]

Resistance to mating by females has been hypothesized as a tactic to assess potential mates and avoid undesirable ones. Previous studies show infection with the pathogenic bacteria, Pseudomonas aeruginosa, triggers a costly immune response and negatively impacts fitness in the wolf spider Schizocosa ocreata (Hentz 1844). Studies also show that infection can be transmitted during copulation, suggesting that there are potential fitness costs associated with mating with an infected individual. We examined impacts of infection on mating interactions of male and female S. ocreata. As studies show infection can be detected through chemical cues, we tested whether males or females avoid mating with infected individuals when given the opportunity. We paired infected and uninfected (control) males and females and recorded their behavior. We found that mating outcome was independent of infection for males and females. While higher male courtship rates and more frequent female receptivity displays were associated with successful mating, we saw no direct effect of infection status on mating outcome. However, among spider pairs that did not mate, females were found to be significantly more resistant and aggressive toward infected males than control males. Male aggression, on the other hand, was greater in pairs that did result in mating. These results suggest that sexual conflict in mating can be related to infection status, and that females can recognize infected males and alter their behavior in response. [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]