The phylogenetic structure and coalescent species delimitation of an endemic trapdoor spider genus, Stasimopus (Araneae, Mygalomorphae, Stasimopidae) in the Karoo region of South Africa.

The Karoo region of South Africa is a unique and sensitive ecosystem which is facing pressure for development due to economic incentives such as mining, farming and shale gas exploration. The species diversity of many taxa in the area is largely unknown. A phylogenetic analysis of the cork-lid trapdoor spider genus, Stasimopus (Stasimopidae) was undertaken in order to gain insight into the relationships between the species that may be present in the area. The species within Stasimopus are challenging to identify and define using traditional morphological methods due to a high degree of morphological conservatism within the genus. For this reason, multiple coalescent based species delimitation methods were used to attempt to determine the species present for Stasimopus in the region which was tested against the morphological identifications and genetic clades (based on CO1, 16S and EF-1É£). We tested single-locus methods Automatic Barcode Gap Discovery (ABGD), Bayesian implementation of Poisson Tree Processes (bPTP) and General Mixed Yule- Coalescent (GMYC), as well as multi-locus Brownie. The phylogenetic analysis of Stasimopus in the Karoo showed that there is a high degree of genetic diversity within the genus. The species delimitation results proved unfruitful for the genus, as they appear to delimit population structure rather than species for most methods. Alternative methods should be investigated to aid in the identification of the species in order truly understand the species diversity of the genus.

Three new genera of arboreal dark sac spiders from southern Africa (Araneae: Trachelidae).

As part of a revision of the Afrotropical species of Trachelas L. Koch, 1872 (Araneae: Trachelidae), we distinguished three new genera of primarily arboreal spiders from southern Africa that are described here: Coronarachne gen. nov., represented by four new species known from both sexes, C. denticulata sp. nov. (type species), C. penicillus sp. nov., C. setosa sp. nov. and C. unigena sp. nov., and C. neethlingi sp. nov., known only from the male; Falcaranea gen. nov., represented by three new species known from both sexes, F. amatola sp. nov., F. gladius sp. nov. (type species) and F. maputensis sp. nov.; and Trachecymbius gen. nov., represented by five new species, T. bosselaersi sp. nov. (), T. felis sp. nov. (), T. peterwebbi sp. nov. (), T. tyume sp. nov. (type species, ), and T. umbella sp. nov. (). These three genera share the presence of strongly protruding setal bases on the ventral surfaces of the anterior legs, which are more strongly developed in males and can be mistaken for small ventral cusps that are found in several trachelid genera. Identification keys are provided for each of the three genera and their phylogenetic affinities to other Afrotropical Trachelidae are evaluated based on the cytochrome oxidase c subunit I (COI) gene. Most of the species described here were common in canopy fogging samples, and to a lesser extent beating, but are clearly a prominent component of the arboreal trachelid fauna in savanna and forest habitats in southern Africa.

Endosymbiont diversity across native and invasive brown widow spider populations.

The invasive brown widow spider, Latrodectus geometricus (Araneae: Theridiidae), has spread in multiple locations around the world and, along with it, brought associated organisms such as endosymbionts. We investigated endosymbiont diversity and prevalence across putative native and invasive populations of this spider, predicting lower endosymbiont diversity across the invasive range compared to the native range. First, we characterized the microbial community in the putative native (South Africa) and invasive (Israel and the United States) ranges via high throughput 16S sequencing of 103 adult females. All specimens were dominated by reads from only 1-3 amplicon sequence variants (ASV), and most individuals were infected with an apparently uniform strain of Rhabdochlamydia. We also found Rhabdochlamydia in spider eggs, indicating that it is a maternally-inherited endosymbiont. Relatively few other ASV were detected, but included two variant Rhabdochlamydia strains and several Wolbachia, Spiroplasma and Enterobacteriaceae strains. We then diagnostically screened 118 adult female spiders from native and invasive populations specifically for Rhabdochlamydia and Wolbachia. We found Rhabdochlamydia in 86% of individuals and represented in all populations, which suggests that it is a consistent and potentially important associate of L. geometricus. Wolbachia was found at lower overall prevalence (14%) and was represented in all countries, but not all populations. In addition, we found evidence for geographic variation in endosymbiont prevalence: spiders from Israel were more likely to carry Rhabdochlamydia than those from the US and South Africa, and Wolbachia was geographically clustered in both Israel and South Africa. Characterizing endosymbiont prevalence and diversity is a first step in understanding their function inside the host and may shed light on the process of spread and population variability in cosmopolitan invasive species.

An integrative taxonomy of the genus Stasimopus Simon 1892 (Araneae: Mygalomorphae) of the Karoo with the description of nine new species and a Stasimopus maraisi Hewitt 1914 male.

The genus Stasimopus Simon 1892 is endemic to Southern Africa, but is historically largely understudied. This paper provides a taxonomic revision for the Stasimopus species of the Karoo region of South Africa and includes the description of nine new species (S. dylani sp. nov., S. finni sp. nov., S. hamartia sp. nov., S. ignis sp. nov., S. karooensis sp. nov., S. malesociatus sp. nov., S. tera sp. nov., S. theaei sp. nov. and S. venterstadensis sp. nov.). A description of the genetically matched S. maraisi Hewitt 1914 male is provided. The original S. maraisi male is designated to its own new species (S. malesociatus sp. nov.). An identification key is provided for species occurring in the Karoo region. This is the first integrative taxonomy for the genus that includes morphological, geometric morphometric as well as genetic data.

Neglected no longer: Phylogenomic resolution of higher-level relationships in Solifugae.

Advanced sequencing technologies have expedited resolution of higher-level arthropod relationships. Yet, dark branches persist, principally among groups occurring in cryptic habitats. Among chelicerates, Solifugae ("camel spiders") is the last order lacking a higher-level phylogeny and have thus been historically characterized as "neglected [arachnid] cousins". Though renowned for aggression, remarkable running speed, and xeric adaptation, inferring solifuge relationships has been hindered by inaccessibility of diagnostic morphological characters, whereas molecular investigations have been limited to one of 12 recognized families. Our phylogenomic dataset via capture of ultraconserved elements sampling all extant families recovered a well-resolved phylogeny, with two distinct groups of New World taxa nested within a broader Paleotropical radiation. Divergence times using fossil calibrations inferred that Solifugae radiated by the Permian, and most families diverged prior to the Paleogene-Cretaceous extinction, likely driven by continental breakup. We establish Boreosolifugae new suborder uniting five Laurasian families, and Australosolifugae new suborder uniting seven Gondwanan families using morphological and biogeographic signal.

The South African genus Lepthercus Purcell, 1902 (Araneae: Mygalomorphae): phylogeny and taxonomy.

After more than a century, the genus Lepthercus Purcell, 1902 is revised. Lepthercus dregei Purcell, 1902 and L. rattrayi Hewitt, 1917 are redescribed; with the female of L. dregei described for the first time. Nine new species of Lepthercus are described. A phylogenetic analysis with morphological characters using implied weights and parsimony as optimality criteria, suggests the separation of the genus in two clades. The first clade is formed by L. dippenaarae sp. nov., L. engelbrechti sp. nov., L. haddadi sp. nov., L. rattrayi Hewitt, 1917 and L. sofiae sp. nov., here denominated "Group haddadi". The species L. confusus sp. nov., Lepthercus dregei Purcell, 1902, Lepthercus filmeri sp. nov., Lepthercus kwazuluensis sp. nov., Lepthercus lawrencei sp. nov. and Lepthercus mandelai sp. nov., form the second clade, here denominated "Group dregei". The "Group haddadi" is characterized by males with a curved metatarsus I, and a swollen tibia I. The "Group dregei" is supported by the presence of small maxillary cuspules in males. A new diagnosis is provided for Lepthercus as well as an identification key for all species of the genus. New distribution maps for the genus in the country are also presented.

A survey of Diphya Nicolet, 1849 (Araneae: Tetragnathidae) from South Africa.

In this paper, five species of Diphya Nicolet, 1849 are recognized in the fauna of South Africa. Four of these species are new: D. foordi sp. nov. (♂♀), D. leroyorum sp. nov. (♂), D. vanderwaltae sp. nov. (♀) and D. wesolowskae sp. nov. (♂♀). The male of D. simoni Kauri, 1950 is described for the first time. Diphya tanikawai Marusik, 2017 syn. nov. was found to be a junior synonym of D. simoni. Descriptions with illustrations, photographs and SEM images are provided for all species. The relationship between the South African and the Neotropical Diphya species is briefly discussed.

Jocquestus, a new genus of trachelid sac spiders from the Afrotropical Region (Arachnida: Araneae).

The new dark sac spider genus Jocquestus gen. nov. (Araneae: Trachelidae) is proposed for two species of Afrotropical trachelid spiders, J. schenkeli (Lessert, 1923) comb. nov. (type species) from D.R. Congo, South Africa, Mozambique and Zimbabwe, and J. roeweri (Lawrence, 1938) comb. nov. from South Africa, both of which are transferred from Trachelas L. Koch, 1872. Both species are redescribed and the male of J. roeweri comb. nov. is described for the first time. Five new species are described: J. capensis sp. nov. (♂ ♀), J. harrisi sp. nov. (♀) and J. incurvus sp. nov. (♂ ♀) from South Africa, and J. griswoldi sp. nov. (♂) and J. obliquus sp. nov. (♂ ♀) from Tanzania. Present data suggests that all of the species are arboreal spiders associated with the vegetation of woody plants in savanna, forest and fynbos habitats, and are only very rarely encountered near the soil surface.