Molecular phylogeny illuminates Amblyopinini (Coleoptera: Staphylinidae) rove beetles as a target for systematic and evolutionary research

The rove beetle tribe Amblyopinini (Coleoptera: Staphylinidae: Staphylininae) is a recently discovered monophyletic lineage comprising an estimated 1000 or more species of mainly leaf- and log litter-dwelling predatory insects found throughout the southern hemisphere. Of these, a single genus Heterothops Stephens somehow conquered all continents in the northern hemisphere as well. A few lineages of amblyopinines independently evolved into highly derived predators of mammal ectoparasites from free-living ancestors. In return, they are tolerated in the mammal fur and nests, which is a unique example of cleaning symbiosis between insects and vertebrates. For over a century the great majority of free-living southern amblyopinines were incorrectly placed in the northern hemisphere-restricted, and superficially similar, rove beetle genera from the subtribe Quediina. Only their mammal-associated derived forms were understood as amblyopinines, a nonmonophyletic taxon of volatile status and enigmatic sister-group relationships of its various members. Here we present the first comprehensive phylogeny of Amblyopinini inferred with Bayesian analysis of a six-gene molecular dataset (4672 bp) across a broad sample of taxa (90 species). This phylogeny provides a framework for the badly needed taxonomic inventory of this group and, in particular, reveals at least two independent origins of mammal association within the tribe. It frames the upcoming in-depth interdisciplinary exploration of a variety of phenomena such as evolution of the austral biota in response to continental drift and climate change, biotic exchange between southern and northern continents, origin and evolution of beetle–mammal symbiosis, and pathways and constraints of the evolutionary parallelisms.     

Modern methods of intraspecies typing of Sonne shigellae. II. Spread of Sonne shigellae of different biochemical types]

The paper presents the results of studying peculiarities of the Sh. sonnei of different biochemical types spread established by their typing scheme suggested by the authors earlier according to rhamnose, xylose and maltose. The epidemic process in dysentery both during the years of the rise and of the decline of its incidence at various territories of the countries proved to be maintained on account of circulation of Sh. sonnei of various biochemical types. The results of studying their dissociative and virulent properties confirmed the biological separation of individual biochemical types. An interrelationship between the character of the biochemical pattern of Shigellae sonnei at the individual territories and the persisting activity of different ways of dysentery transmission was determined. The results of studying the biochemical pattern could be used as an indicator of the degree of activity of individual ways of dysentery spread at various territories.     

Are subcortical rove beetles truly Holarctic? An integrative taxonomic revision of north temperate Quedionuchus (Coleoptera: Staphylinidae: Staphylininae)

Organisms Diversity & Evolution - The recognition of Holarctic species, those shared between Nearctic and Palaearctic regions, often implies continuous or recent events of gene flow across the...     

The past and the present through phylogenetic analysis: the rove beetle tribe Othiini now and 99 Ma

In order to classify and taxonomically describe the first two fossil Othiini (Coleoptera: Staphylinidae: Staphylininae) species from three well‐preserved specimens in Cretaceous Burmese amber, a phylogenetic analysis was conducted, combining extant and extinct taxa. A dataset of 76 morphological characters scored for 33 recent species across the subfamilies Staphylininae and Paederinae was analysed using maximum parsimony and Bayesian inference methods. The many differing phylogenetic hypotheses for higher‐level relationships in the large rove beetle subfamilies Staphylininae and Paederinae were summarized and their hitherto known fossil record was reviewed. Based on the analyses, the new extinct genus Vetatrecus gen.n. is described with two new species: V. adelfiae sp.n. and V. secretum sp.n. Both species share character states that easily distinguish them from all recent Othiini and demonstrate a missing morphological link between subfamilies Staphylininae and Paederinae. This is the first morphology‐based evidence for the paraphyly of Staphylininae with respect to Paederinae, suggested earlier by two independent molecular‐based phylogenies of recent taxa. Our newly discovered stem lineage of Othiini stresses the importance of fossils in phylogenetic analyses conducted with the aim of improving the natural classification of extant species. It also suggests that the definitions of Staphylininae and Paederinae, long‐established family‐group taxa, may have to be reconsidered. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:817F39C4-F36B-4FD9-96CD-5F8FB064C39E .     

Regulated Gene Expression as a Tool for Analysis of Heterochromatin Position Effect in <Emphasis Type="Italic">Drosophila</Emphasis>

Position effect variegation (PEV) is a perturbation of genes expression resulting from the changes in their chromatin organization due to the abnormal juxtaposition with heterochromatin. The exact molecular mechanisms of PEV remain enigmatic in spite of the long history of PEV studies. Here, we developed a genetic model consisting of PEV-inducing chromosome rearrangement and a reporter gene under control of the UAS regulatory element. Expression of the reporter gene could be regulated by adjustment of the GAL4 transactivator activity. Two UAS-based systems of expression control were tested–with thermosensitive GAL4 repressor GAL80^ts and GAL4-based artificial transactivator GeneSwitch. Both systems were able to regulate the expression of the UAS-controlled reporter gene over a wide range, but GAL80^ts repressed the reporter gene more efficiently. Measurements of the heterochromatin-mediated repression of the reporter gene in the GAL4+GAL80^ts system point to the existence of a threshold level of expression, above which no PEV is observed.     

The characteristics of the biological properties of Shigella dysenteriae 1 circulating in the USSR and India: its biochemical activity and agglutinability

The properties of 71 S. dysenteriae 1 strains isolated from patients in the USSR and India in 1986-1988 were studied. The cultures possessed typical biochemical and serological properties. As revealed in this investigation, high fastidiousness of this infective agent to the quality of synthetic nutrient could become the cause of false negative reactions in different substrates used for the identification of enterobacteria, thus leading to diagnostic mistakes. The variability of the biochemical activity of different strains with respect to arginine, glycerol, maltose and trehalose (as well as the stability of these signs) was regarded as the theoretical substantiation of the possibility, in principle, to work out the scheme for the subdivision of S. dysenteriae 1 into independent biochemical variants.