Progress in erigonine spider phylogeny—the <Emphasis Type="Italic">Savignia</Emphasis>-group is not monophyletic (Araneae: Linyphiidae)

We present the most inclusive study on the higher-level phylogeny of erigonine spiders, including about 30% of all erigonine genera. By expanding the previously most comprehensive analysis (Miller and Hormiga Cladistics 20:385–442, 2004) we tested the robustness of its results to the addition of closely related taxa, and also the monophyly of the Savignia-group defined by Millidge (Bulletin of the British Arachnological Society 4:1–60, 1977). The character matrix was expanded by adding 18 newly scored species in 15 genera, and also includes all species scored by other authors. This adds up to 98 species in 91 erigonine genera plus 13 outgroup taxa. The parsimony analysis led to eight fully resolved most parsimonious trees (L=1084). The topology concerning the taxa basal to the ‘distal erigonines’ remained unchanged, and the latter clade still shares 67% of all nodes with the original analysis. The Savignia-group is not monophyletic at genus level with respect to Saloca diceros and Alioranus pastoralis, and the same applies at species level in Diplocephalus and Erigonella. From the Savignia-group, Glyphesis servulus, Diplocephalus cristatus, Savignia frontata, and two representatives each of Erigonella, Dicymbium and Araeoncus combine to form a monophyletic clade.     

The female genitalic morphology of “micronetine” spiders (Araneae,Linyphiidae)

Current knowledge of “micronetine” female genitalia is almost exclusively based on transmitted light microscopy data. As such, our understanding of the epigynal anatomy is incomplete and somewhat misleading, to the extent that it hinders comparative studies of linyphiid diversity. We used scanning electronic microscopy (SEM) to study the complex epigynal morphology of “micronetine” spiders. Enzymatic digestion of soft tissues allowed us to examine the internal chitinized structures in detail using SEM. A taxonomic sample of nine species was selected to represent the morphological genitalic diversity of female “micronetines” (including one member of the Erigoninae clade). Results reveal that the epigynum consists of a pair of grooves formed by integument folds (copulatory and fertilization grooves). The protruding epigynal region is divided into a ventral and a dorsal plate by the grooves; both plates can be modified to form an epigynal cavity and/or a scape. Our observations confirm the widespread occurrence of epigynal grooves, rather than ducts, in “micronetines”. Epigynal grooves seem to be common in linyphioids and other spider groups.     

Molecular phylogeny of the bee genus Hoplitis (Megachilidae: Osmiini) – how does nesting biology affect biogeography?

The genus Hoplitis (Megachilidae: Osmiini) comprises about 360 described species and occurs on all continents except Australia, South America, and Antarctica. Using five genes, we inferred the phylogeny of Hoplitis including 23 out of the 27 currently recognized subgenera, applying both Bayesian and maximum likelihood methods. Compared to the current morphology‐based classification, our phylogeny resulted in three classificatory changes: first, the subgenera Alcidamea, Cyrtosmia, Dasyosmia, Megalosmia, Monumetha, and Prionohoplitis are merged into one large subgenus Alcidamea Cresson, 1864, comb. nov. ; second, the subgenera Annosmia, Bytinskia, Coloplitis, and Hoplitis are merged into one large subgenus Hoplitis Klug, 1807, comb. nov. ; third, the subgenera Acrosmia, Hoplitina, Penteriades, and Proteriades are merged into one large subgenus Proteriades Titus, 1904, comb. nov. We provide evidence that the genus Hoplitis has a Palaearctic origin and that colonization events to southern Africa and to the Nearctic, as well as recolonization events from the Nearctic to the Palaearctic occurred. The species of the genus Hoplitis exhibit an extraordinary diversity in nesting behaviour, comprising both below and above ground nesting. Parsimony mapping revealed that ground nesting in excavated burrows is the ancestral state amongst Hoplitis bees. We hypothesize that nesting biology strongly affected both range expansion and long‐distance dispersal in Hoplitis. © 2012 The Linnean Society of London     

A new species of Tarsonops (Araneae,Caponiidae) from southern Belize,with a key to the genera?of?the?subfamily Nopinae

A new species of Caponiidae, Tarsonops irataylori sp. n. is described from southern Belize, and a key to the genera of the subfamily Nopinae is provided.     

Characterizing the vibratory and acoustic signals of the “purring” wolf spider,Gladicosa gulosa (Araneae: Lycosidae)

Both airborne acoustic signals and substrate-borne vibrations are prevalent modes of animal communication, particularly in arthropods. While a wide variety of animals utilize one or both of these modalities, the connection between them is still ambiguous in many species. Spiders as a group are not known for using, or even perceiving, acoustic signals, despite being well-adapted for vibratory communication. Males of the “purring” wolf spider Gladicosa gulosa are reported to produce audible signals during courtship, although the literature on this species is largely anecdotal. Using a laser Doppler vibrometer and an omnidirectional microphone in controlled conditions, we recorded and characterized the visual and mechanical (both substrate-borne and airborne) signals of this species in an attempt to provide a qualitative and quantitative overview of its signal properties. We found that the vibratory signal is composed of two primary repeating and alternating elements, consisting of pulses of stridulation and percussive strikes, as well as a less common, but repeatable, third element. We also characterized a measurable airborne component to the signal that is significantly correlated with the amplitude of the vibratory signal, which we suggest is a by-product of the strong vibration. Neither modality correlated significantly with male body size or condition. Although the exact role of the acoustic component is unclear, we speculate that the unique properties of signalling in this species may have value in answering new questions about animal communication.     

Kleptoparasites or commensals? Effects of Argyrodes antipodianus (Araneae: Theridiidae) on Nephila plumipes (Araneae: Tetragnathidae)

Argyrodes antipodianus is a small kleptobiotic spider that steals prey from webs of the large orb-weaving spider Nephila plumipes, and sometimes removes the web itself. We used experiments in a greenhouse to test how the presence of the kleptobiont, differences in food availability, and web damage affected fitness of the web owner. After 49 days, N. plumipes with four A. antipodianus on their webs gained 55% less weight and relocated their webs 4.5 times as often as spiders with no kleptobionts. Increased web relocation and decreased weight gain may have resulted from reduced prey levels or from web damage by A. antipodianus. A second experiment demonstrated that hosts gained weight at the feeding rate used in the first experiment, but not at lower rates. Web relocation rate also varied with feeding rate, but in a non-linear manner. Web loss was evaluated in a separate experiment, by manually removing one-quarter of the web every 5 days for 30 days; however, neither weight gain nor rate of web relocation were affected. We conclude that A. antipodianus is a true kleptoparasite that can reduce the growth rate of its host N. plumipes, but that neither food theft nor web damage alone explain increased web relocation rates. Received: 28 November 1996 / Accepted: 3 April 1997     

A review of the spider genus Haplodrassus Chamberlin, 1922 in Crimea (Ukraine) and adjacent areas (Araneae, Gnaphosidae)

Eight species of Haplodrassus are recorded from Crimea: Haplodrassus bohemicus Miller & Buchar, 1977; Haplodrassus dalmatensis (L. Koch, 1866); Haplodrassus isaevi Ponomarev & Tsvetkov, 2006; Haplodrassus minor (O. P.-Cambridge, 1879); Haplodrassus kulczynskii Lohmander, 1942; Haplodrassus pseudosignifer Marusik, Hippa & Koponen, 1996; Haplodrassus signifer (C.L. Koch, 1839) and Haplodrassus umbratilis (L. Koch, 1866). The occurrence of Haplodrassus cognatus (Westring, 1861) in Crimea has not been confirmed. Haplodrassus bohemicus is a new species record for the Crimean fauna. Haplodrassus pseudosignifer is a new species record for Crimea and Ukraine as a whole, with Crimea as the westernmost point of its distribution range. Haplodrassus invalidus is recorded for the first time for the fauna of Azerbaijan, Caucasus and the former Soviet Union. Azerbaijan is the easternmost point of its known distribution range. All Crimean Haplodrassus species have only one peak of activity of adult specimens during the year. In Crimea we found syntopically two closely related species Haplodrassus dalmatensis and Haplodrassus isaevi in two localities (Sudak Distr., 10 km W Sudak, Mezhdurechie Vill., steppe; and Feodosiya Distr., Karadag Nature Reserve, steppes). These species differ in their phenology. The reproductive period of Haplodrassus dalmatensis isin May-July, and that of Haplodrassus isaevi occurs is in October-December. These phenological differences probably represent an additional mechanism of reproductive isolation between the two species. Diagnostic drawings are provided for all mentioned species as well as for Haplodrassus deserticola Schmidt & Krause, 1996 and Haplodrassus pugnans (Simon, 1880).     

Livestock QTLs — bringing home the bacon?

Markers have been used for some time to study the genetic control of economically important traits in livestock. The early work was based on single loci and detected some significant effects, but results were often inconsistent across studies. Now that complete microsatellite-based maps of the major species are becoming available, more complete and rigorous scans of the genome are possible. The first of these have detected some surprisingly large effects, both within breeds and in breed crosses. As research workers digest these results and their implications for livestock breeding programmes and ponder further research, commercial breeding companies have already started applying the first fruits of marker research to breed a better animal.     

Seed plant phylogeny: Demise of the anthophyte hypothesis?

Recent molecular phylogenetic studies indicate, surprisingly, that Gnetales are related to conifers, or even derived from them, and that no other extant seed plants are closely related to angiosperms. Are these results believable? Is this a clash between molecules and morphology?     

Mesobuthus gibbosus (Scorpiones: Buthidae) on the island of Rhodes — hybridization between Ulysses’ stowaways and native scorpions?

Allozyme data suggest that the Rhodes population of Mesobuthus gibbosus is a hybrid population of recent origin. Namely, it is a mixture between an autochthonous population and an artificially introduced population probably from the Greek mainland. All samples were mainly composed of F1 hybrid genotypes and genotypes either fixed for autochthonous or introduced alleles. Back-cross hybrid genotypes were very rare. Mitochondrial DNA analysis, in contrast, revealed only one group of closely related haplotypes that are unique for the Rhodes populations, thus suggesting asymmetric introgression of the two marker classes.     

Effects of anthropogenic factors on spider communities (Arthropoda: Araneae) in Chréa National park (Blida,Algeria)

Chréa National Park, one of the 11 national parks in Algeria, is natural and diverse but under different pressures: urbanisation, fires caused by the high flux of visitors. Several ecological and systematic studies have been conducted on the Araneae, the most important epigeal fauna, but no attention was given to the anthropogenic parcels of the Park. To assess the effects of urbanisation and fires on the ecology of this fauna, spiders were collected monthly for 2 years, using ‘Pitfall’ traps in three disturbed stations: burned, urbanised and reforested and three natural sites as control. In total, 1,476 specimens were sampled (19 families, 42 genera and 68 species). Zodarion algericum was the dominant species (13.25%), particularly in the burned station. Mann–Whitney U test showed a significant difference between urbanised and nonurbanised sites in contrast to other ones and no significant differences with the control. Our results show that fires transform the forest into a mosaic of habitats, with open gaps of different stages of succession. In addition, the reforestation of cedars without any agricultural practices has no negative effects on the Park. No loss of biodiversity was observed; this would encourage the restoration of the forest to protect its fauna and flora.     

The ‘kinetochore maintenance loop’—The mark of regulation?

Kinetochores can form and be maintained on DNA sequences that are normally non‐centromeric. The existence of these so‐called neo‐centromeres has posed the problem as to the nature of the epigenetic mechanisms that maintain the centromere. Here we highlight results that indicate that the amount of CENP‐A at human centromeres is tightly regulated. It is also known that kinetochore assembly requires sister chromatid cohesion at mitosis. We therefore suggest that separation or stretching between the sister chromatids at metaphase reciprocally determines the amount of centromere assembly in the subsequent interphase. This reciprocal relationship forms the basis of a negative feedback loop that could precisely control the amount of CENP‐A and faithfully maintain the presence of a kinetochore over many cell divisions. We describe how the feedback loop would work, propose how it could be tested experimentally and suggest possible components of its mechanism.     

Phylogeny of γ‐proteobacteria: resolution of one branch of the universal tree?

The reconstruction of bacterial evolutionary relationships has proven to be a daunting task because variable mutation rates and horizontal gene transfer (HGT) among species can cause grave incongruities between phylogenetic trees based on single genes. Recently, a highly robust phylogenetic tree was constructed for 13 gamma-proteobacteria using the combined alignments of 205 conserved orthologous proteins.1 Only two proteins had incongruent tree topologies, which were attributed to HGT between Pseudomonas species and Vibrio cholerae or enterics. While the evolutionary relationships among these species appears to be resolved, further analysis suggests that HGT events with other bacterial partners likely occurred; this alters the implicit assumption of gamma-proteobacteria monophyly. Thus, any thorough reconstruction of bacterial evolution must not only choose a suitable set of molecular markers but also strive to reduce potential bias in the selection of species.     

Two new species of the genera Mysmena and Trogloneta (Mysmenidae,Araneae) from Southwestern?China

Two new spider species of the family Mysmenidae Petrunkevitch, 1928 are reported from Southwestern China, i.e., Mysmena wawuensissp. n. (male and female) from Sichuan and Trogloneta yuensissp. n. (male) from Chongqing. Diagnoses and illustrations of the new species are provided.     

First description of the female of the jumping spider Balmaceda nigrosecta Mello-Leit?o (Salticidae,Dendryphantini, Marpissina)

The female of Balmacedanigrosecta Mello-Leitão, 1945 is described and illustrated for the first time. In addition, this paper further illustrates the male, and provides the first known observations on the natural history of this species, including habitat, cohabitation, and prey capturedata.