More data, fewer shifts: Molecular insights into the evolution of the spinning apparatus in non-orb-weaving spiders

Advances in the reconstruction of the spider tree of life: A roadmap for spider systematics and comparative studies

In the last decade and a half, advances in genetic sequencing technologies have revolutionized systematics, transforming the field from studying morphological characters or a few genetic markers, to genomic datasets in the phylogenomic era. A plethora of molecular phylogenetic studies on many taxonomic groups have come about, converging on, or refuting prevailing morphology or legacy-marker-based hypotheses about evolutionary affinities. Spider systematics has been no exception to this transformation and the inter-relationships of several groups have now been studied using genomic data. About 51 500 extant spider species have been described, all with a conservative body plan, but innumerable morphological and behavioural peculiarities. Inferring the spider tree of life using morphological data has been a challenging task. Molecular data have corroborated many hypotheses of higher-level relationships, but also resulted in new groups that refute previous hypotheses. In this review, we discuss recent advances in the reconstruction of the spider tree of life and highlight areas where additional effort is needed with potential solutions. We base this review on the most comprehensive spider phylogeny to date, representing 131 of the 132 spider families. To achieve this sampling, we combined six Sanger-based markers with newly generated and publicly available genome-scale datasets. We find that some inferred relationships between major lineages of spiders (such as Austrochiloidea, Palpimanoidea and Synspermiata) are robust across different classes of data. However, several new hypotheses have emerged with different classes of molecular data. We identify and discuss the robust and controversial hypotheses and compile this blueprint to design future studies targeting systematic revisions of these problematic groups. We offer an evolutionary framework to explore comparative questions such as evolution of venoms, silk, webs, morphological traits and reproductive strategies.

Dynamic evolution of locomotor performance independent of changes in extended phenotype use in spiders

Many animals use self-built structures (extended phenotypes) to enhance body functions, such as thermoregulation, prey capture or defence. Yet, it is unclear whether the evolution of animal constructions supplements or substitutes body functions-with disparate feedbacks on trait evolution. Here, using brown spiders (Araneae: marronoid clade), we explored if the evolutionary loss and gain of silken webs as extended prey capture devices correlates with alterations in traits known to play an important role in predatory strikes-locomotor performance (sprint speed) and leg spination (expression of capture spines on front legs). We found that in this group high locomotor performance, with running speeds of over 100 body lengths per second, evolved repeatedly-both in web-building and cursorial spiders. There was no correlation with running speed, and leg spination only poorly correlated, relative to the use of extended phenotypes, indicating that web use does not reduce selective pressures on body functions involved in prey capture and defence per se. Consequently, extended prey capture devices serve as supplements rather than substitutions to body traits and may only be beneficial in conjunction with certain life-history traits, possibly explaining the rare evolution and repeated loss of trapping strategies in predatory animals.

A novel probe set for the phylogenomics and evolution of RTA spiders

Spiders are important models for evolutionary studies of web building, sexual selection and adaptive radiation. The recent development of probes for UCE (ultra-conserved element)-based phylogenomic studies has shed light on the phylogeny and evolution of spiders. However, the two available UCE probe sets for spider phylogenomics (Spider and Arachnida probe sets) have relatively low capture efficiency within spiders, and are not optimized for the retrolateral tibial apophysis (RTA) clade, a hyperdiverse lineage that is key to understanding the evolution and diversification of spiders. In this study, we sequenced 15 genomes of species in the RTA clade, and using eight reference genomes, we developed a new UCE probe set (41 845 probes targeting 3802 loci, labelled as the RTA probe set). The performance of the RTA probes in resolving the phylogeny of the RTA clade was compared with the Spider and Arachnida probes through an in-silico test on 19 genomes. We also tested the new probe set empirically on 28 spider species of major spider lineages. The results showed that the RTA probes recovered twice and four times as many loci as the other two probe sets, and the phylogeny from the RTA UCEs provided higher support for certain relationships. This newly developed UCE probe set shows higher capture efficiency empirically and is particularly advantageous for phylogenomic and evolutionary studies of RTA clade and jumping spiders.

The life aquatic with spiders (Araneae): repeated evolution of aquatic habitat association in Dictynidae and allied taxa

Despite the dominance of terrestriality in spiders, species across a diverse array of families are associated with aquatic habitats. Many species in the spider family Dictynidae are associated with water, either living near it or, in the case of Argyroneta aquatica, in it. Previous studies have indicated that this association arose once within the family. Here we test the hypothesis of a single origin via the broadest phylogeny of dictynids and related ‘marronoids’ to date, using several taxa that were not previously sampled in molecular analyses to provide the first quantitative test of the hypothesis put forth by Wheeler et al. (2016). We sampled 281 terminal taxa from 14 families, assembling a matrix with 4380 total base pairs of data from most taxa. We also assembled an atlas of morphological traits with potential significance for both ecology and taxonomy. Our resulting trees indicate that an aquatic habitat association has arisen multiple times within dictynids. Dictynidae and the genus Dictyna are polyphyletic and the genera Lathys and Cicurina remain unplaced. A review of aquatic habitat associations in spiders indicates that it occurs in members of at least 21 families. With our morphological atlas, we explore characters that have been implicated in aiding an aquatic lifestyle, which in the past may have caused confusion regarding taxon placement. Our results indicate that not all spiders with traits thought to be useful for aquatic habitat associations occupy such habitats, and that some spider taxa lacking these traits are nonetheless associated with water.

The changing use of the ovipositor in host shifts by ichneumonid ectoparasitoids of spiders (Hymenoptera, Ichneumonidae, Pimplinae)

Accurate egg placement into or onto a living host is an essential ability for many parasitoids, and changes in associated phenotypes, such as ovipositor morphology and behaviour, correlate with significant host shifts. Here, we report that in the ichneumonid group of koinobiont spider-ectoparasitoids (“polysphinctines”), several putatively ancestral taxa (clade I here), parasitic on ground-dwelling RTA-spiders (a group characterised by retrolateral tibial apophysis on male palpal tibiae), lay their eggs in a specific way. They tightly bend their metasoma above the spider’s cephalothorax, touching the carapace with the dorsal side of the ovipositor apically (“dorsal-press”). The egg slips out from the middle part of the ventral side of the ovipositor and moves towards its apex with the parted lower valves acting as rails. Deposition occurs as the parasitoid draws the ovipositor backwards from under the egg. Oviposition upon the tough carapace of the cephalothorax, presumably less palatable than the abdomen, is conserved in these taxa, and presumed adaptive through avoiding physical damage to the developing parasitoid. This specific way of oviposition is reversed in the putatively derived clade of polysphinctines (clade II here) parasitic on Araneoidea spiders with aerial webs, which is already known. They bend their metasoma along the spider’s abdomen, grasping the abdomen with their fore/mid legs, pressing the ventral tip of the metasoma and the lower valves of the ovipositor against the abdomen (“ventral-press”). The egg is expelled through an expansion of the lower valves, which is developed only in this clade and evident in most species, onto the softer and presumably more nutritious abdomen.

Extinction vs. Rapid Radiation: The Juxtaposed Evolutionary Histories of Coelotine Spiders Support the Eocene-Oligocene Orogenesis of the Tibetan Plateau

Evolutionary biology has long been concerned with how changing environments affect and drive the spatiotemporal development of organisms. Coelotine spiders (Agelenidae: Coelotinae) are common species in the temperate and subtropical areas of the Northern Hemisphere. Their long evolutionary history and the extremely imbalanced distribution of species richness suggest that Eurasian environments, especially since the Cenozoic, are the drivers of their diversification. We use phylogenetics, molecular dating, ancestral area reconstructions, diversity, and ecological niche analyses to investigate the spatiotemporal evolution of 286 coelotine species from throughout the region. Based on eight genes (6.5 kb) and 2323 de novo DNA sequences, analyses suggest an Eocene South China origin for them. Most extant, widespread species belong to the southern (SCG) or northern (NCG) clades. The origin of coelotine spiders appears to associate with either the Paleocene-Eocene Thermal Maximum or the hot period in early Eocene. Tibetan uplifting events influenced the current diversity patterns of coelotines. The origin of SCG lies outside of the Tibetan Plateau. Uplifting in the southeastern area of the plateau blocked dispersal since the Late Eocene. Continuous orogenesis appears to have created localized vicariant events, which drove rapid radiation in SCG. North-central Tibet is the likely location of origin for NCG and many lineages likely experienced extinction owing to uplifting since early Oligocene. Their evolutionary histories correspond with recent geological evidence that high-elevation orographical features existed in the Tibetan region as early as 40-35 Ma. Our discoveries may be the first empirical evidence that links the evolution of organisms to the Eocene-Oligocene uplifting of the Tibetan Plateau. [Tibet; biogeography; ecology; molecular clock; diversification.].

Spider phylogenomics: untangling the Spider Tree of Life

Spiders (Order Araneae) are massively abundant generalist arthropod predators that are found in nearly every ecosystem on the planet and have persisted for over 380 million years. Spiders have long served as evolutionary models for studying complex mating and web spinning behaviors, key innovation and adaptive radiation hypotheses, and have been inspiration for important theories like sexual selection by female choice. Unfortunately, past major attempts to reconstruct spider phylogeny typically employing the "usual suspect" genes have been unable to produce a well-supported phylogenetic framework for the entire order. To further resolve spider evolutionary relationships we have assembled a transcriptome-based data set comprising 70 ingroup spider taxa. Using maximum likelihood and shortcut coalescence-based approaches, we analyze eight data sets, the largest of which contains 3,398 gene regions and 696,652 amino acid sites forming the largest phylogenomic analysis of spider relationships produced to date. Contrary to long held beliefs that the orb web is the crowning achievement of spider evolution, ancestral state reconstructions of web type support a phylogenetically ancient origin of the orb web, and diversification analyses show that the mostly ground-dwelling, web-less RTA clade diversified faster than orb weavers. Consistent with molecular dating estimates we report herein, this may reflect a major increase in biomass of non-flying insects during the Cretaceous Terrestrial Revolution 125-90 million years ago favoring diversification of spiders that feed on cursorial rather than flying prey. Our results also have major implications for our understanding of spider systematics. Phylogenomic analyses corroborate several well-accepted high level groupings: Opisthothele, Mygalomorphae, Atypoidina, Avicularoidea, Theraphosoidina, Araneomorphae, Entelegynae, Araneoidea, the RTA clade, Dionycha and the Lycosoidea. Alternatively, our results challenge the monophyly of Eresoidea, Orbiculariae, and Deinopoidea. The composition of the major paleocribellate and neocribellate clades, the basal divisions of Araneomorphae, appear to be falsified. Traditional Haplogynae is in need of revision, as our findings appear to support the newly conceived concept of Synspermiata. The sister pairing of filistatids with hypochilids implies that some peculiar features of each family may in fact be synapomorphic for the pair. Leptonetids now are seen as a possible sister group to the Entelegynae, illustrating possible intermediates in the evolution of the more complex entelegyne genitalic condition, spinning organs and respiratory organs.

Gastrulation occurs in multiple phases at two distinct sites in Latrodectus and Cheiracanthium spiders

BACKGROUND

The longstanding canonical model of spider gastrulation posits that cell internalization occurs only at a unitary central blastopore; and that the cumulus (dorsal organizer) arises from within the early deep layer by cell-cell interaction. Recent work has begun to challenge the canonical model by demonstrating cell internalization at extra-blastoporal sites in two species (Parasteatoda tepidariorum and Zygiella x-notata); and showing in Zygiella that the prospective cumulus internalizes first, before other cells are present in the deep layer. The cell behaviors making up spider gastrulation thus appear to show considerable variation, and a wider sampling of taxa is indicated.

RESULTS

We evaluated the model in three species from two families by direct observation of living embryos. Movements of individual cells were traced from timelapse recordings and the origin and fate of the cumulus determined by CM-DiI labeling. We show that there are two distinct regions of internalization: most cells enter the deep layer via the central blastopore but many additional cells ingress via an extra-blastoporal ring, either at the periphery of the germ disc (Latrodectus spp.) or nearer the central field (Cheiracanthium mildei). In all species, the cumulus cells internalize first; this is shown by tracing cells in timelapse, histology, and by CM-DiI injection into the deep layer. Injection very early in gastrulation labels only cumulus mesenchyme cells whereas injections at later stages label non-cumulus mesoderm and endoderm.

CONCLUSIONS

We propose a revised model to accommodate the new data. Our working model has the prospective cumulus cells internalizing first, at the central blastopore. The cumulus cells begin migration before other cells enter the deep layer. This is consistent with early specification of the cumulus and suggests that cell-cell interaction with other deep layer cells is not required for its function. As the cumulus migrates, additional mesendoderm internalizes at two distinct locations: through the central blastopore and at an extra-blastoporal ring. Our work thus demonstrates early, cell-autonomous behavior of the cumulus and variation in subsequent location and timing of cell internalization during gastrulation in spiders.

Total evidence analysis of the phylogenetic relationships of Lycosoidea spiders (Araneae, Entelegynae)

Phylogenetic relationships within the superfamily Lycosoidea are investigated through the coding and analysis of character data derived from morphology, behaviour and DNA sequences. In total, 61 terminal taxa were studied, representing most of the major groups of the RTA-clade (i.e. spiders that have a retrolateral tibial apophysis on the male palp). Parsimony and model-based approaches were used, and several support values, partitions and implied weighting schemes were explored to assess clade stability. The morphological–behavioural matrix comprised 96 characters, and four gene fragments were used: 28S (~737 base pairs), actin (~371 base pairs), COI (~630 base pairs) and H3 (~354 base pairs). Major conclusions of the phylogenetic analysis include: the concept of Lycosoidea is restricted to seven families: Lycosidae, Pisauridae, Ctenidae, Psechridae, Thomisidae, Oxyopidae (but Ctenidae and Pisauridae are not monophyletic) and also Trechaleidae (not included in the analysis); the monophyly of the ‘Oval Calamistrum clade’ (OC-clade) appears to be unequivocal, with high support, and encompassing the Lycosoidea plus the relimited Zoropsidae and the proposed new family Udubidae (fam. nov.); Zoropsidae is considered as senior synonym of Tengellidae and Zorocratidae (syn. nov.); Viridasiinae (rank nov.) is raised from subfamily to family rank, excluded from the Ctenidae and placed in Dionycha. Our quantitative phylogenetic analysis confirms the synonymy of Halidae with Pisauridae. The grate-shaped tapetum appears independently at least three times and has a complex evolutionary history, with several reversions.

Molecular phylogeny of the spider family Sparassidae with focus on the genus Eusparassus and notes on the RTA-clade and 'Laterigradae'

The phylogeny of the spider family Sparassidae is comprehensively investigated using four molecular markers (mitochondrial COI and 16S; nuclear H3 and 28S). Sparassidae was recovered as monophyletic and as most basal group within the RTA-clade. The higher-level clade Dionycha was not but monophyly of RTA-clade was supported. No affiliation of Sparassidae to other members of the 'Laterigradae' (Philodromidae, Selenopidae and Thomisidae) was observed, and the crab-like posture of this group assumed a result of convergent evolution. Only Philodromidae and Selenopidae were found members of a supported clade, but together with Salticidae and Corinnidae, while Thomisidae was nested within the higher Lycosoidea. Within Sparassidae monophyly of the subfamilies Heteropodinae sensu stricto, Palystinae and Deleninae was recovered. Sparianthinae was supported as the most basal clade within Sparassidae. Sparassinae and the genus Olios were found each to be polyphyletic. Eusparassinae was not recovered monophyletic, with the two original genera Eusparassus and Pseudomicrommata in separate clades and only the latter clustered with most other assumed Eusparassinae, here termed the "African clade". Further focus was on the monophyletic genus Eusparassus and its proposed species groups, of which the dufouri-, walckenaeri- and doriae-group were confirmed as monophyletic with the two latter groups more closely related. According to molecular clock analyses, the divergence time of Sparassidae and Eusparassus was estimated with 186 and 70 million years ago respectively.

Systematics of Cauquenia (Araneae : Zoropsidae), with comments on the patterns of evolution of cribellum and male tibial crack on Lycosoidea

A new genus of the spider family Zoropsidae, Cauquenia, gen. nov., is proposed for Cauquenia maule, sp. nov., from the Maule region in central Chile. The familial placement is tested through the inclusion of Cauquenia in the latest major published morphological analyses of the superfamily Lycosoidea, and the subfamily placement of the South American zoropsid genus Itatiaya Mello-Leitão is also tested including them in the Raven and Stumkat (2005) analysis. Cauquenia and Itatiaya are closely related to the African genera Griswoldia Dippenaar-Schoeman & Jocqué and Phanotea Simon, with which it shares a cup-shaped median apophysis on the male pedipalp and tooth-like projections on the lateral lobes of the epigyne in females. The patterns of evolution of the cribellum and the male tibial crack in Lycosoidea are explored; the cribellum shows up as primitively present, with three losses and four independent acquisitions, and the male tibial crack is lost twice. An asymmetric cost in cribellum gain : loss of 6 : 1 produces a primitive cribellum with 12 losses.

A preliminary molecular analysis of phylogenetic and biogeographic relationships of New Zealand Thomisidae (Araneae) using a multi-locus approach

We tested competing theories on the origins of the New Zealand fauna using thomisid spiders as a model group. These theories can be broadly described as old and vicariant versus young and recent (dispersal). To test these theories, a phylogenetic analysis was undertaken based on cytochrome c oxidase subunit I (COI) and 28S rRNA sequence data, with smaller datasets (histone H3, nicotinamide adenine dinucleotide (NADH) dehydrogenase subunit 1 and a combined dataset) used to improve resolution of internal branches. The monophyly of New Zealand thomisid subfamilies and of individual taxa were also assessed using these data. Our data supports the separation of New Zealand clades from their Australian counterparts. Evidence of recent dispersal to New Zealand by Australian stephanopines combined with our proposed maximum divergence date of 5.3 mya indicates that the New Zealand thomisids are a younger lineage than previously suspected. Several other gene targets (internal transcribed spacer units 1 and 2, wingless and 18S rRNA) were examined but did not generate sufficient reliable data to contribute to the analysis. Corrected p-distance values for COI indicate that Sidymella angularis, a widely distributed and morphologically variable stephanopine species, is a single taxon. Three undescribed endemic species exhibited molecular and morphological distinctiveness from previously described New Zealand thomisids.

The velvet spiders: an atlas of the Eresidae (Arachnida, Araneae)

The family Eresidae C. L. Koch, 1850 is reviewed at the genus level. The family comprises nine genera including one new genus. They are: Adonea Simon, 1873, Dorceus C. L. Koch, 1846, Dresserus Simon, 1876, Eresus Walckenaer, 1805, Gandanameno Lehtinen, 1967, Loureediagen. n., ParadoneaLawrence, 1968, Seothyra Purcell, 1903, and Stegodyphus Simon, 1873. A key to all genera and major lineages is provided along with corresponding diagnoses, as well as descriptions of selected species. These are documented with collections of photographs, scanning electron micrographs, and illustrations. A new phylogeny of Eresidae based on molecular sequence data expands on a previously published analysis. A species of the genus Paradonea Lawrence, 1968 is sequenced and placed phylogenetically for the first time. New sequences from twenty Gandanameno Lehtinen, 1967 specimens were added to investigate species limits within the genus. The genus Loureediagen. n. is proposed to accommodate Eresus annulipes Lucas, 1857. Two species, Eresus semicanus Simon, 1908 and Eresus jerbae El-Hennawy, 2005, are synonymized with Loureedia annulipescomb. n. One new species, Paradonea presleyisp. n. is described. Eresus algericus El-Hennawy, 2004 is transferred to Adonea Simon, 1873. The female of Dorceus fastuosus C. L. Koch, 1846 is described for the first time. The first figures depicting Paradonea splendens (Lawrence, 1936) are presented.

Resting metabolic rates of two orbweb spiders: a first approach to evolutionary success of ecribellate spiders

Spiders are considered conservative with regard to their resting metabolic rate, presenting the same allometric relation with body mass as the majority of land-arthropods. Nevertheless, web-building is thought to have a great impact on the energetic metabolism, and any modification that affects this complex behavior is expected to have an impact over the daily energetic budget. We analyzed the possibility of the presence of the cribellum having an effect on the allometric relation between resting metabolic rate and body mass for an ecribellate species (Zosis geniculata) and a cribellate one (Metazygia rogenhoferi), and employed a model selection approach to test if these species had the same allometric relationship as other land-arthropods. Our results show that M. rogenhoferi has a higher resting metabolic rate, while Z. geniculata fitted the allometric prediction for land arthropods. This indicates that the absence of the cribellum is associated with a higher resting metabolic rate, thus explaining the higher promptness to activity found for the ecribellate species. If our result proves to be a general rule among spiders, the radiation of Araneoidea could be connected to a more energy-consuming life style. Thus, we briefly outline an alternative model of diversification of Araneoidea that accounts for this possibility.

Patterns of habitat affinity and Austral/Holarctic parallelism in dictynoid spiders (Araneae:Entelegynae)

The ability to survive in a terrestrial environment was a major evolutionary hurdle for animals that, once passed, allowed the diversification of most arthropod and vertebrate lineages. Return to a truly aquatic lifestyle has occurred only rarely among terrestrial lineages, and is generally associated with modifications of the respiratory system to conserve oxygen and allow extended periods of apnea. Among chelicerates, in particular spiders, where the circulatory system also serves as a hydrostatic skeleton, very few taxa have exploited aquatic environments, though these environments are abundant and range from freshwater ponds to the marine intertidal and relictual (salt) lakes. The traditional systematic positions of the taxa inhabiting these environments are controversial. Partitioned Bayesian analysis using a doublet model for stems in the nearly complete 18S rRNA gene (~1800 nt) and in the D2 and D3 regions of the 28S rRNA gene (~690 nt), and standard models for loops and full protein-coding histone H3 (349 nt) partitions (totalling 3133 bp when aligned) of dictynoid spiders and related lineages revealed that the only truly aquatic spider species, Argyroneta aquatica (Clerck, 1767) (Cybaeidae Banks, 1892), belongs in a clade containing other taxa with unusual habitat affinities related to an aquatic existence, including occupation of semi-aquatic (intertidal) areas (Desidae Pocock, 1985: Paratheuma spp.) and highly alkaline salt-crusts (Dictynidae O. Pickard-Cambridge, 1871: Saltonia incerta (Banks, 1898)). In a contrasting pattern, other spiders that also occupy intertidal zones, including some other members of the family Desidae (Desis spp., Badumna longinqua (L. Koch, 1867)), are an independently derived clade found primarily in the southern hemisphere. Use of the doublet model reduced some branch-support values in the single-gene trees for rRNA data, but resulted in a robust combined-data phylogeny from 18S rRNA, 28S rRNA, and histone H3. This combination of results – reduction in support in single-gene trees and gain in support in combined-data trees –is consistent with use of the doublet model reducing problematic signal from non-independent base pairs in individual data partitions, resulting in improved resolution in the combined-data analyses.

Reconstructing web evolution and spider diversification in the molecular era

The evolutionary diversification of spiders is attributed to spectacular innovations in silk. Spiders are unique in synthesizing many different kinds of silk, and using silk for a variety of ecological functions throughout their lives, particularly to make prey-catching webs. Here, we construct a broad higher-level phylogeny of spiders combining molecular data with traditional morphological and behavioral characters. We use this phylogeny to test the hypothesis that the spider orb web evolved only once. We then examine spider diversification in relation to different web architectures and silk use. We find strong support for a single origin of orb webs, implying a major shift in the spinning of capture silk and repeated loss or transformation of orb webs. We show that abandonment of costly cribellate capture silk correlates with the 2 major diversification events in spiders (1). Replacement of cribellate silk by aqueous silk glue may explain the greater diversity of modern orb-weaving spiders (Araneoidea) compared with cribellate orb-weaving spiders (Deinopoidea) (2). Within the "RTA clade," which is the sister group to orb-weaving spiders and contains half of all spider diversity, >90% of species richness is associated with repeated loss of cribellate silk and abandonment of prey capture webs. Accompanying cribellum loss in both groups is a release from substrate-constrained webs, whether by aerially suspended webs, or by abandoning webs altogether. These behavioral shifts in silk and web production by spiders thus likely played a key role in the dramatic evolutionary success and ecological dominance of spiders as predators of insects.

Systematics of Nearctic Cybaeus (Araneae:Cybaeidae)

Spiders in the genus Cybaeus L. Koch (Araneae : Dictynoidea : Cybaeidae) are common forest-floor inhabitants in western North America and Japan. Here we establish an initial phylogenetic framework for North American Cybaeus. Morphological details for eight proposed species groups are given, and these results, combined with molecular analyses of one nuclear and one mitochondrial gene for six of the eight species groups, suggest that North American Cybaeus species are contained in two broad clades, one Holarctic and one Nearctic (primarily Californian). The Holarctic clade contains the tetricus and angustiarum species groups, which contain mostly widely distributed species. The Californian clade includes the adenes, aspenicolens, consocius, devius, septatus and tardatus species groups, all of which have very restricted ranges. The genus Cybaeus and the Palaearctic species C. tetricus (C.L. Koch) (type species of the genus) and C. angustiarum L. Koch are redescribed and illustrated. A key to species groups is provided. Nine new species endemic to the western Nearctic and included in the molecular analyses are described and illustrated: C. paralypropriapus Bennett, sp. nov. and C. waynei Bennett, sp. nov. (tetricus group); C. sanbruno Bennett, sp. nov. (adenes group); C. thermydrinos Bennett, sp. nov. (aspenicolens group); C. penedentatus Bennett, sp. nov. and C. vulpinus Bennett, sp. nov. (consocius group); C. chauliodous Bennett, sp. nov. and C. somesbar Bennett, sp. nov. (septatus group); and C. gidneyi Bennett, sp. nov. (unplaced).

Revision of coelotine spiders from Nepal (Araneae:Amaurobiidae)

Coelotine spiders from Nepal are studied based on collections from the Himalaya Expeditions of J. Martens carried out in the years 1969, 1970, 1973, 1980, 1983, 1988 and 1995. In total, 38 Nepalese species of the genus Draconarius Ovtchinnikov, 1999 are described, including 35 new species. These are: D. beloniforis, sp. nov. (♂), D. bifarius, sp. nov. (♂), D. brevikarenos, sp. nov. (♀), D. capitellus, sp. nov. (♀), D. communis, sp. nov. (♂♀), D. condocephalus, sp. nov. (♂♀), D. confusus, sp. nov. (♂♀), D. contiguus, sp. nov. (♀), D. cylindratus, sp. nov. (♀), D. dapaensis, sp. nov. (♂), D. distinctus, sp. nov. (♂♀), D. dorsicephalus, sp. nov. (♂♀), D. gorkhaensis, sp. nov. (♂♀), D. gurkha (Brignoli, 1976) (♀), D. latiforus, sp. nov. (♀), D. meganiger, sp. nov. (♀), D. microcoelotes, sp. nov. (♀), D. panchtharensis, sp. nov. (♀), D. paraepisomos, sp. nov. (♂♀), D. phulchokiensis, sp. nov. (♀), D. pseudogurkha, sp. nov. (♀), D. pseudomeganiger, sp. nov. (♀), D. sacculus, sp. nov. (♀), D. schawalleri, sp. nov. (♂), D. semicirculus, sp. nov. (♂♀), D. seorsus, sp. nov. (♀), D. simplicifolis, sp. nov. (♀), D. spinosus, sp. nov. (♂♀), D. subconfusus, sp. nov. (♀), D. subepisomos, sp. nov. (♂♀), D. subrotundus, sp. nov. (♀), D. taplejungensis, sp. nov. (♀), D. testudinatus, sp. nov. (♀), D. tinjuraensis, sp. nov. (♂♀), D. tritos, sp. nov. (♂♀), D. volutobursarius, sp. nov. (♂♀), D. wuermlii (Brignoli, 1978) (♀) and D. yadongensis (Hu & Li, 1987) (♂♀). The male is described for the first time for D. yadongensis. The distribution characteristics of Nepalese coelotines are discussed. The phylogenetic relationships of Coelotinae, including Nepalese coelotines and the two recently established coelotine genera, Lineacoelotes Xu, Li & Wang, 2008 and Notiocoelotes Wang, Xu & Li, 2008 from China and South-east Asia, are analysed using the parsimony method. Our research found that coelotines from Nepal are highly diversified and occur in different clades of the tree. The genus Draconarius is not monophyletic. We assigned all the species examined in this study to Draconarius because they are not congeneric with any existing coelotine genus. Their appropriate placement will be further studied in a future phylogenetic analysis using all coelotine species as terminals.