Allochthonius (Pseudoscorpiones: Pseudotyrannochthoniidae) is a genus widely distributed throughout East Asia. In Korea, only three species in this genus have been recorded to date: Allochthonius buanensis Lee, 1982; Allochthonius coreanus Morikawa, 1970; and Allochthonius opticus Ellingsen, 1907. Here, we review the Korean fauna of Allochthonius and describe three new species for the country: Allochthonius jungsuni sp. nov., Allochthonius maximus sp. nov., and Allochthonius rufimanus sp. nov. We also exclude Allochthonius opticus -a species originally described from Japan-from the country record and redescribe two Korean recorded species, Allochthonius buanensis and Allochthonius coreanus. Following up on our previous taxonomic work that elevated several subspecies of Japanese pseudotyrannochthoniids originally described by Kuniyasu Morikawa to species level, we elevate eight former subspecies to full species rank: A. ishikawai deciclavatus Morikawa, 1956 = A. deciclavatus Morikawa, 1956, stat. nov., A. ishikawai ishikawai Morikawa, 1954 = A. ishikawai Morikawa, 1954, A. ishikawai kyushuensis Morikawa, 1960 = A. kyushuensis Morikawa, 1960, stat. nov., A. ishikawai shiragatakiensis Morikawa, 1954 = A. shiragatakiensis Morikawa, 1954, stat. nov., A. ishikawai uenoi Morikawa, 1956 = A. uenoi Morikawa, 1956, stat. nov., and A. ishikawai uyamadensis Morikawa, 1954 = A. uyamadensis Morikawa, 1954, stat. nov.; A. opticus opticus Ellingsen, 1907 = A. opticus Ellingsen, 1907, and A. opticus troglophilus Morikawa, 1956 = A. troglophilus Morikawa, 1956, stat. nov.. This elevates the total number of Allochthonius species from 40 to 43, of which five species are presently known from the Korean Peninsula.

A fossil assigned to the extant ixodid genus Haemaphysalis was previously described from the Late Cretaceous (ca. 99 Ma) Burmese amber. Haemaphysalis (Alloceraea) cretacea was considered the oldest, and only, fossil representative of this genus. Significant criticism was raised regarding possible misidentification of this amber fossil. Microtomography of the original holotype and new material allows new perspectives on this controversy. A new fossil nymph is described and both fossils are considered Alloceraea cretacea comb. nov. nymphs based on a series of morphological characters: no genital aperture, eyeless, 11 festoons, coxa I simple with a short, wide triangular spur. Specific morphological features for the 'structurally primitive' Alloceraea are discussed and include palpi elongate, with long setae on palps, the hypostome dorsally longer than the chelicera and the corona visible distally and with a specific distribution of the denticles. Alloceraea and its sister genus Archaeocroton (that includes amber fossil taxa), share a common ancestor with Haemaphysalis sensu stricto, indicating a minimum divergence time of at least 100 MYA for these lineages. In addition, a fossil of Bothriocroton has also been described from Burmese amber. This genus with Cryptocroton groups basal to the Alloceraea/Archaecroton-Haemaphysalis assemblage forming a monophyletic clade named Haematobothrion. A synthesis of the fossil information and the current systematic understanding of the Haematobothrion allows new hypotheses about the origins of this group and the various lineages it comprises. Notably that the major Haematobothrion lineages originated and diverged during the time period when the Burma terrane was migrating from Australia to Asia.

Pseudoscorpions (Arachnida: Pseudoscorpiones) are amongst the oldest terrestrial lineages but their fossil record is still very sparse. In recent years, Upper Cretaceous Burmese amber has emerged as an important source for fossil pseudoscorpions. In this study, we extend the fossil record of the family Chernetidae Menge, 1855 – one of the most diverse pseudoscorpion families – by at least 20 million years through the description of a new genus and species, †Burmachernes gen. nov. for the new species †Burmachernes cenomanium sp. nov. from this amber deposit. Although †Burmachernes exhibits the principle synapomorphy of Chernetidae, namely venom glands in the movable chelal finger, it is distinguished from all 121 extant genera as well as the Eocene fossil genus †Oligochernes Beier, 1937 by a unique combination of characters, including trichobothrial arrangement, chaetotaxy, and cheliceral morphology. This fossil represents a significant discovery that fills an important gap in the evolutionary history of Chernetidae, extends the temporal range of the family further back into the Mesozoic, and demonstrates that chernetid pseudoscorpions had already evolved morphological features closely resembling those of their extant relatives.

The enigmatic spider family Gradungulidae, endemic to Australia and New Zealand, exhibits a combination of morphological characteristics from both modern and early branching lineages. These spiders are rare, challenging to collect, and not well documented, with only 18 described species across seven genera. This study presents the first comprehensive review of the gradungulid fauna in New Zealand, utilising extensive field sampling, molecular phylogenetics, and high-resolution imaging. Previously, this fauna was understood to comprise three monotypic genera: Gradungula , Pianoa and Spelungula . However, we discovered an unexpected diversity of gradungulids in the northern region of New Zealand's South Island, both genetically and taxonomically. This led to the identification of several new candidate species, including Gradungula kahurangi, sp. nov. and Pianoa civis, sp. nov., which are formally described from adult males. Despite high diversity in the north of the South Island, these genera exhibit notable differences in their biogeographical distribution: the forest-dwelling Pianoa and cave-inhabiting Spelungula are climatic relicts with limited distribution ranges and poor dispersal capabilities, whereas Gradungula sorenseni shows a widespread distribution extending to the southernmost region of the South Island. Overall, this study establishes a significant framework for conservation biology concerning some of New Zealand's most iconic yet rare spiders. Additionally, revised and expanded diagnoses of male genitalia for the New Zealand genera are presented.

The fossil record of the six living smaller arachnid orders is reviewed. Palpigradi (palpigrades) are represented by two fossil species, respectively from the mid-Cretaceous Burmese amber of Myanmar and the Pliocene Onyx Marble of the USA. Solifugae (camel spiders) are known from six unequivocal species from the Late Carboniferous Coal Measures of the USA, the Early Cretaceous Crato Formation of Brazil, the slightly younger Burmese amber, from Baltic amber (Paleogene: Eocene) and from Dominican amber (Neogene: Miocene). Ricinulei (ricinuleids), with twenty-three fossil species in total, are surprisingly diverse in Northern hemisphere Coal Measures and Cretaceous Burmese amber, but do not occur in younger ambers. Amblypygi (whip spiders) first occur unequivocally in the Coal Measures. There are thirteen fossils in total, with further records from the Crato Formation and in Burmese amber, as well as in the Indian Cambay amber (Paleogene: Eocene), Chiapas or Mexican amber (Paleogene–Neogene: Oligocene/Miocene) and the near contempary (Miocene) Dominican amber. Thelyphonida (whip scorpions) are known from fourteen species and are again found in the Coal Measures, the Crato Formation and Burmese amber, but do not occur in younger ambers. Schizomida (schizomids) are known from fourteen species; eight from Burmese amber, with additional species in Dominican amber and the Onyx Marble. The wider significance of the fossil record for the evolutionary history, morphological evolution and historical biogeography of each of these six orders, and arachnids in general, is discussed.

Poorly dispersing pseudoscorpions (Arachnida: Pseudoscorpiones) are often considered suitable models for biogeography studies. Several lineages show interesting distribution patterns, such as the genus Parobisium Chamberlin, 1930 that occurs in the western U.S.A. and easternAsia but is absent in Europe and central Asia. Here we review the pseudoscorpion genus Parobisium using an integrative taxonomic approach and describe two new species from South Korea based on morphological and molecular data: Parobisium namkungi sp. nov. and P. troglophilum sp. nov. Phylogenetic analyses using three genetic markers, cytochrome c oxidase subunit I (COI), histone H3A, and 28S ribosomal DNA also reveal that two former subspecies, P. magnum ohuyeanum (Morikawa, 1952) and P. magnum chejuense (Morikawa, 1970), are genetically distinct enough to recognize them as separate species, P. ohuyeanum stat nov. and. P. chejuense stat. nov. The phylogenetic data show that there is an old split between the East Asian and North American lineages that is indicative of ancient vicariance rather than recent dispersal. Similar biogeographic patterns have been reported in other poorly dispersing invertebrate taxa, such as Grylloblattidae and flightless beetles, which also show deep genetic divergences across these landmasses. We hypothesize that Parobisium may once have been widespread in Holarctic but subsequently became restricted to isolated fragments in East Asia and North America.

Australian salt lakes are distinctive ecosystems that support specialized biota and provide opportunities to study evolutionary and biogeographic processes. Many salt lakes occur along ancient river channels (palaeodrainage systems), which form natural replicates for testing hypotheses of vicariance and dispersal among isolated habitats. We examined the phylogeography and genetic structure of the Australian wolf spider Lycosa salifodina McKay, 1976, a salt lake habitat specialist widespread across south-western Australia. We tested the hypothesis that genetic structure in L. salifodina primarily reflects long-term isolation among palaeodrainage systems, with reduced population structuring in more frequently inundated and interconnected lakes. Phylogenetic analyses of mitochondrial CO1 sequences from 26 specimens (collected 2023–2024) recovered three major clades (A–C) largely corresponding to discrete palaeodrainage systems. Clade A, occurring in north-western palaeodrainages (e.g. Lakes Barlee, Giles and Moore), showed >5% divergence from other clades. Clade B comprised populations from north-eastern inland palaeodrainages (Lakes Raeside, Ballard, Rebecca and Marmion), while Clade C included southern, near-coastal populations spanning multiple palaeodrainage systems. Genetic divergence within clades was low (1–3% pairwise divergence), with no haplotype sharing among localities. Molecular dating suggests that the L. salifodina complex originated approximately 15 million years ago during the Miocene, with divergence among the three major clades occurring within the last 4 million years, coinciding with increased salinization of palaeodrainage systems. Stronger genetic isolation in northern inland populations and weaker structuring in southern coastal lakes support the hypothesis that palaeodrainage history and hydrological connectivity jointly shape diversification in this species.

Despite its broad distribution across arid and semi-arid regions of Africa, Asia, southern Europe, and Australia, the pseudoscorpion genus Olpium L. Koch, 1873 (Pseudoscorpiones: Olpiidae) remains taxonomically neglected in Iran and only two species (O. omanense Mahnert, 1991 and O. lindbergi Beier, 1959) have been recorded from this country to date. Following detailed morphological study of extensive field collections in Iran, we describe two new species, O. tenebris sp. nov. and O. lacustre sp. nov., that are widely distributed across the country. Comprehensive descriptions, illustrations, and comparisons with closely related species are provided. To facilitate standardized identification and character evaluation, we present an updated species-level key for the genus Olpium, constructed using DELTA software.

Species of the pseudoscorpion genus Mundochthonius (Chthoniidae) are difficult to distinguish using traditional morphology, as diagnostic traits exhibit limited variation despite substantial genetic divergence. Here, we used publicly available sequence data to reconstruct the phylogeny of Japanese Mundochthonius and applied multiple species-delimitation methods to assess diversity and biogeographic patterns. Phylogenetic analyses recovered seven major genetic clades consistent with previous studies, while five delimitation approaches indicated substantially higher species diversity than currently recognized. These clades exhibit strong geographic structuring: clades 1, 3, 5, 6, and 7 are restricted to eastern Japan, whereas clade 4 is broadly distributed in western Japan, a pattern corresponding to the Itoigawa-Shizuoka Tectonic Line, which demarcates the western boundary of the Fossa Magna region. We describe Mundochthonius tsushimaensis sp. nov., a genetically distinct lineage endemic to Tsushima Island, which is situated between the Korean peninsula and Kyushu island of the Japanese Archipelago. Although the new species lacks clear morphological differentiation from other members of the clade, it displays a COI p-distance of 14% from all congeners, indicating substantial genetic divergence that is further corroborated by the geographical isolation of the island. Additionally, we elevate Mundochthonius japonicus scolytidis to species rank (Mundochthonius scolytidis stat. nov.) based on genetic distinctiveness. We propose that the phylogeographic structure of Japanese Mundochthonius reflects a refugial model, where deeply divergent, range-restricted eastern clades originated on the complex geological history of the Japanese Archipelago. These findings underscore the importance of integrating molecular and biogeographic data for resolving taxonomy in morphologically conserved groups.

Forest restoration often involves monitoring programmes to determine whether biodiversity levels and ecosystem services have changed over time. This study investigated changes in ground-hunting spider communities (families Ctenidae, Lycosidae and Zodariidae) in an actively restored forest, an unrestored gravel mine, and two alternative land-use types (agroforestry system and an arable field) to assess whether a two-decade post-mine restoration programme has been successful in restoring biodiversity to levels of a reference natural forest. The overall activity density of ground-hunting spiders (based on both juveniles and adult specimens) was highest in the natural and the restored forest in the dry season and lowest in the arable field and agroforestry system in the wet season. The inverse Simpson index was highest at the gravel site in the wet season, followed by natural forest in both seasons and lower values in the restored forest. The community composition of spiders differed significantly between land-use types (open versus forest habitats) and the interaction between land use and season also differed significantly. The species Pardosa injucunda and Trochosa gentilis dominated the communities in the restored forest, but Africactenus monitor dominated the natural forest and Hogna gratiosa dominated communities in the gravel site. Surprisingly, active forest restoration promoted the activity density of ground-hunting spiders displaced by mining activities to levels even higher than in the reference natural forest after two decades. However, the community composition of the restored forest was more similar to the agroforestry system than to the natural forest. These results highlight the benefits of restoring former mining sites but also show the trade-offs in terms of restoration goals, as natural forest biodiversity of spiders was not achieved after 20 years.

Integrative taxonomy facilitates determining species boundaries in morphologically conserved taxa with limited dispersal abilities, such as litter-dwelling pseudoscorpions in the genus Allochthonius (family Pseudotyrannochthiniidae). This genus is common in East Asia but taxonomically challenging due to its cryptic morphology and variable diagnostic characters. We present a multi-locus phylogeny of Allochthonius in Japan, Korea, and Taiwan, including 55 newly-acquired specimens from 11 locations across Taiwan. We find that Allochthonius in Taiwan is monophyletic and comprises multiple undescribed species. Consolidating morphology with molecular species delimitation based on three tree-based or distance-based methods, we recognize seven new species with replicable morphological and molecular differences: A. agyaqensis sp. nov., A. aquaeductensis sp. nov., A. brunus sp. nov., A. kiunnensis sp. nov., A. nebulosus sp. nov., A. nubicolus sp. nov., and A. tamanensis sp. nov. Phylogenetic analyses and divergence time estimations suggest that Taiwanese Allochthonius separated from its Korea-Japan relatives ca. 15 million years ago, and that cooling climates during the Late Miocene and subsequent warming and rapid uplift of the Central Mountain Range during Pliocene likely promoted diversification. Spatial mapping suggests that litter-dwelling Allochthonius species living in tropical and subtropical montane regions may have a sky-island distribution with high endemism and naturally small distribution ranges.

Karst research in Korea is still in its infancy and the invertebrate fauna of subterranean systems across the country is poorly known. One of the very diverse lineages in caves across Korea, the pseudoscorpions, are almost undocumented although they represent stunning examples of cave adaptations and troglomorphism. In this study, we provide a phylogenetic hypothesis for the pseudoscorpion Spelaeochthonius Morikawa, 1954 (Pseudoscorpiones: Pseudotyrannochthoniidae) in South Korea; a genus that exclusively occurs in caves across China, Japan and the Korean Peninsula. We report seven species of which four are newly described and illustrated based on molecular, distributional and morphological data: Spelaeochthonius dugigulensis sp. nov., S. geumgulensis sp. nov., S. magwihalmigulensis sp. nov. and S. yamigulensis sp. nov. All species are strongly cave-adapted and known from a single cave or karst system only, emphasizing the need to implement conservation strategies for Korean karst systems and their fauna.

The Sydney funnel-web spider Atrax robustus O. Pickard-Cambridge, 1877 is an iconic Australian species and considered among the most dangerously venomous spiders for humans. Originally described in 1877 from a single specimen collected in “New Holland”, this spider has a complex taxonomic history. The most recent morphological revision of funnel-web spiders (Atracidae) lists this species as both widespread and common in the Sydney Basin bioregion and beyond, roughly 250 km from the Newcastle area south to the Illawarra, and extending inland across the Blue Mountains. Morphological variability and venom diversity in this species appear to be unusually high, raising questions about species concepts and diversity in these spiders. In this study, we use a combination of molecular phylogenetics, divergence time analyses and morphology to establish the Sydney funnel-web spider as a complex of three species. The “real” Sydney funnel-web spider Atrax robustus is relatively widespread in the Sydney metropolitan region. A second species, Atrax montanus (Rainbow, 1914), which is revalidated here, overlaps but mainly occurs further south and west, and a third larger species, Atrax christenseni sp. nov., is found in a small area surrounding Newcastle to the north. The revised taxonomy for funnel-web spiders may have practical implications for antivenom production and biochemical studies on spider venoms. Although no human fatalities have occurred since the development of antivenom in the 1980s, antivenom for Sydney funnel-web spiders might be optimized by considering biological differentiation at the species level.

Conservation management in ancient landscapes has shifted in recent years from the protection of single species to the broader management of areas of high biodiversity. One of the landscapes that has most benefited from this shift is the south-west of Western Australia, an internationally recognised biodiversity hotspot and one of the oldest and most stable landscapes on Earth. Significant progress has been made in recent years to identify refugia in the south-west and prioritise them for invertebrate protection but more studies are still needed to assist practical conservation management. Here, we describe a new genus of pseudoscorpions from south-western Australia (Pseudoscorpiones: Pseudotyrannochthoniidae: Karrichthonius gen. nov. ) that has speciated extensively within mesic refugia. Karrichthonius is endemic to the High Rainfall Province of the biodiversity hotspot and features often-localised populations in spatially isolated mesic habitats. Through a combination of DNA barcoding, morphological features and spatial mapping, we infer 12 species: Karrichthonius giganteus (Beier, 1971) comb. nov. , K. booraraensis , sp. nov. , K. buzattoi , sp. nov. , K. dalei , sp. nov. , K. farquhari , sp. nov. , K. heatherae , sp. nov. , K. leniae , sp. nov. , K. porongurupensis , sp. nov. , K. pyungurupensis , sp. nov ., K. rixi , sp. nov. , K. talyuberlupensis , sp. nov. and K. toolbrunupensis , sp. nov . All species are short-range endemics and occur in landforms that are either known refugia for invertebrate conservation or inferred here as potential refugia to be recognised and analysed further. By mapping species distributions and providing species diagnoses, we contribute to an understanding of invertebrate biodiversity in the south-west, and strengthen the concepts that are underlying conservation management practices in biodiversity hotspots. ZooBank: urn:lsid:zoobank.org:pub:EC51BFC7-0C8E-49D6-A704-DA59648B2325.

The pseudoscorpion genus Lechytia Balzan, 1892 (Chthoniidae Daday, 1889: Lechytiinae Chamberlin, 1929) includes 27 extant species that are distributed across all continents except Antarctica, and a single extinct species from Dominican amber of Miocene age. We document the first record of Lechytia from Burmese amber (Cenomanian: similar to 99 Ma), Lechytia finniae sp. nov., making it the oldest fossil record for Lechytia and extending the known temporal range of this group by more than 70 million years into the Mesozoic. The new species differs from most extant Lechytia species due to the distance between trichobothria sb and b that are separated by at least one areolar diameter, and by the absence of eyes. Since there is a close morphological resemblance between L. finniae sp. nov. and extant Lechytia species, the new fossil is placed in an extant genus and represents yet another example of morphological stasis in pseudoscorpions. The presence of Lechytia in Burmese amber implies that this genus was present on the Burma Terrane in the Cretaceous although no extant species are known from this landmass today. The ecology of extant species may lend support to a tropical forest environment on the Burma Terrane. (c) 2025 Elsevier Ltd. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

Spiders are dominant predators in terrestrial ecosystems, regulating invertebrate biomass, diversity and abundance through predation. However, analysing predation patterns in the field is challenging, especially as spiders are extra-intestinal liquid feeders and often active at night. Gut content metabarcoding (GCM) provides a cost-effective method to study the prey composition of spiders. In this study, we determine the minimum sample size of spider specimens required to obtain representative estimates of local prey composition. Six common spider species were studied using GCM, and we show that the number of analysed individuals per spider species influenced the sampling completeness for prey at different taxonomic levels. To achieve 90% sampling completeness at the prey species level, between 50 and over 150 individuals per spider species had to be analysed, which is challenging for ecological multi-site studies. Hence, we argue for consideration of coarser taxonomic levels, such as family or order, which often provide sufficient ecological information to understand predator-prey interactions. At these levels, sampling completeness can be achieved with much smaller sample sizes of four to eight individuals per species, making ecological GCM studies more cost-effective. These results highlight the benefits of considering the taxonomic resolution in metabarcoding studies to address ecological research questions. We further provide information that will facilitate future investigations of predator-prey dynamics, not just in spiders but also in other extra-intestinal liquid feeders like, for example, ground beetles.

Two new fossil hard ticks (Arachnida: Ixodida: Ixodidae) from Dominican amber (Miocene, probably Burdigalian, ca. 16 Ma) are described. An almost fully engorged female and a partly engorged larva were documented by combining light microscopy with high-resolution µCT-scans at the Deutsches Elektronen-Synchrotron (DESY) and 3D modelling of the data. Images of the fossils created from these 3D models facilitated comparisons with living ticks and the new material can be assigned to the Recent genus Amblyomma C.L. Koch, 1844 as Amblyomma arawakan Chitimia-Dobler & Martins sp. nov. The new amber species appears to be most closely related to the extant New World tick Amblyomma auricularium Conil, 1878. Possible hosts for the fossils are discussed within the wider context of their historical biogeography.

Two new species of the pseudoscorpion genus Pararoncus Chamberlin, 1938 are described from Korea. Detailed descriptions, habitus pictures, and illustrations of Pararoncus leonardisp. nov. and P. taeyoungisp. nov. are provided. The current distribution of the genus Pararoncus is mapped and a taxonomic key for all species is provided.

Two new species of the spider genus Loxosceles (Araneae: Sicariidae) from the Ecuadorian Andes are described: Loxosceles guayllabamba sp. nov. (male, female) and Loxosceles binfordae sp. nov. (male, female). Both species are part of the second most speciose “laeta” group, which include twenty-four described species. Only three species are known to occur on mainland Ecuador, and one species in the Galapagos. The synonymy of L. alicea under L. rufescens is rejected, detailed SEM of the female internal genitalia and a map of all the species from mainland Ecuador are presented.

Pseudoscorpions have a sparse fossil record although they are among the oldest terrestrial lineages with origins extending to the Devonian (ca. 390 Ma). Amongst the 25 extant families of pseudoscorpions, only 14 are known from fossils, most of which are preserved in European ambers from the Eocene. Fossil pseudoscorpions from the Cretaceous of Europe have only been reported from three localities, Archingeay amber (France), from the Rhenish Massif (Germany), and from Alava and Teruel amber (Spain), but only one of these has ever been formally described. Here we add a new fossil pseudoscorpion genus and species, Ajkagarypinus stephani gen. et sp. nov., from an Upper Cretaceous (Santonian, ca. 86.3-83.6 Ma) amber deposit in the Ajka Coal Formation (Ajka area, Hungary), the so-called Ajkaite. This fossil extends the spatial range of the pseudoscorpion family Garypinidae and suggests that they might have been widespread in the whole Eurasian landmasses under humid, subtropical climatic conditions. (c) 2023 Elsevier Ltd. All rights reserved.