65 research outputs found

    First report of the parasitoid wasps, Microchelonus subcontractus and Bracon intercessor (Hym.: Braconidae), from Iran

    Get PDF
    This paper reports the occurrence of the hymenoterous parasitoids of the beet moth, Scrobipalpa ocellatella Boyd larvae in Iran for the first time. Two braconid species of Microchelonus subcontractus Abdinbekova and Bracon intercessor Nees were collected from the larvae of S. ocellatella in the sugar beet fields located in Ray, the southern district of Tehran. These parasitoids are belonging to the subfamilies Cheloninae and Braconinae, respectively

    Diversity and Distribution of Braconidae, a Family of Parasitoid Wasps in the Central European Peatbogs of South Bohemia, Czech Republic

    Get PDF
    An ecological overview of seven years investigation of Braconidae, a family of parasitoid wasps (Hymenoptera: Ichneumonoidea) and a tyrpho-classification of parasitoids in peatbog areas of South Bohemia, Czech Republic are given. A total of 350 species were recorded in investigated sites, but only five tyrphobionts (1.4%) are proposed: Microchelonus basalis, Microchelonus koponeni, Coloneura ate, Coloneura danica and Myiocephalus niger. All of these species have a boreal-alpine distribution that, in Central Europe, is associated only with peatbogs. Tyrphophilous behaviour is seen in at least four (1.1%) species: Microchelonus pedator, Microchelonus subpedator, Microchelonus karadagi and Microchelonus gravenhorstii; however, a number of other braconids prefer peatbogs because they were more frequently encountered within, rather than outside, the bog habitat. The rest of the braconids (342 species, 97.5%) are tyrphoneutrals, many of them being eurytopic components of various habitats throughout their current ranges. Lists of tyrphobiontic braconids and a brief commentary on species composition, distributional picture of actual ranges, and parasitoid association to bog landscape are provided. Being true refugial habitats for populations in an ever-changing world, peatbogs play a significant role in harboring insect communities

    Human transformations of the Wadden Sea ecosystem through time: a synthesis

    Get PDF
    Todayrsquos Wadden Sea is a heavily human-altered ecosystem. Shaped by natural forces since its origin 7,500 years ago, humans gradually gained dominance in influencing ecosystem structure and functioning. Here, we reconstruct the timeline of human impacts and the history of ecological changes in the Wadden Sea. We then discuss the ecosystem and societal consequences of observed changes, and conclude with management implications. Human influences have intensified and multiplied over time. Large-scale habitat transformation over the last 1,000 years has eliminated diverse terrestrial, freshwater, brackish and marine habitats. Intensive exploitation of everything from oysters to whales has depleted most large predators and habitat-building species since medieval times. In the twentieth century, pollution, eutrophication, species invasions and, presumably, climate change have had marked impacts on the Wadden Sea flora and fauna. Yet habitat loss and overexploitation were the two main causes for the extinction or severe depletion of 144 species (~20% of total macrobiota). The loss of biodiversity, large predators, special habitats, filter and storage capacity, and degradation in water quality have led to a simplification and homogenisation of the food web structure and ecosystem functioning that has affected the Wadden Sea ecosystem and coastal societies alike. Recent conservation efforts have reversed some negative trends by enabling some birds and mammals to recover and by creating new economic options for society. The Wadden Sea history provides a unique long-term perspective on ecological change, new objectives for conservation, restoration and management, and an ecological baseline that allows us to envision a rich, productive and diverse Wadden Sea ecosystem and coastal society

    Parasitoid complex of Stereonychus fraxini (De Geer) (Coleoptera, Curculionidae) in Serbia

    No full text
    The parasitoid complex of the ash weevil Stereonychus fraxini (De Geer) (Coleoptera, Curculionidae) from 20 localities in Serbia was studied. Forty-one samples of ash weevil larvae and cocoons were analyzed, and the presence of parasitoids was confirmed in 24 samples. Ten species of hymenopteran parasitoids (Hymenoptera Parasitica) were recorded. The two common eulophid wasps, Entedon zanara Walker and Entedon cionobius Thompson, were the most abundant. Parasitoids had an insignificant influence on the level of ash weevil population, because the level of infestation did not exceed 20% in 83% of the samples; however infestation above 40% was determined in 12.2% of the samples, indicating that in some cases parasitoids may significantly reduce the ash weevil population. [Projekat Ministarstva nauke Republike Srbije, br. III 43002

    WĂ€rmeliebende Fische auf dem Weg nach Norden

    No full text
    • 

    corecore