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Insecticides have leading role in reduction of population of arthropods, especially vectors of infectious diseases. Efficacy of insecticides is usually proved on biological material and described after adjusting the values of parameters in some “theoretical” function to the experimental results. In the standard approach, such function is described by probit regression. However, in some cases reaction of the population on pesticide differs from those which could be described by the probit regression curve and the results could not be properly assessed. The aim of this study was to elaboratie a practical tool for evaluating insecticide/acaricide efficacy, more universal than classical probit calculation. Software performing analysis was created using R 2.13.1 statistical software.
Arthropods obtained on Rattus norvegicus from Wrocław in 2003-2004 were studied. Also based on literature all arthropods occurring on this host in Poland are mentioned: 3 species of Anoplura, 12 species of Siphonaptera and at least 44 species of Acari. Arthropod communities and dynamic structure of arthropods for brown rat from Poland are given.
Investigation of mixed carbonate−siliciclastic Lower Devonian deposits have been carried out in the Ivanye Zolote and Ustechko sections in Podolia, Ukraine. Based on palynomorph evidence, the age of the samples studied is late Lochkovian, not older than the NM Oppel Miospore Zone, specifically the Si Lineage Zone. The presence of acritarchs and chitinozoans points to dominantly marine depositional conditions. However, a regressive environmental change toward more brackish conditions is indicated by a decrease in the taxonomic diversity of acritarchs in the topmost samples, the simultaneous disappearance of chitinozoans, and an increase in leiosphaerid frequency. Furthermore, evolution of limestone microfacies demonstrates a progressive transition from a shrinking marine basin toward a brackish, storm−affected muddy lagoon, manifested by recurrent profusion of impoverished, mostly opportunistic and euryhaline shelly benthos (nuculanid bivalves, leperditicopids and other ostracods, terebratulid brachiopods), chaetetid demosponges and diverse ichthyofauna. The association of plant (mainly nematophytes and some tracheids) and animal (eurypterid, ?scorpion, and possibly other arthropod) remains points to the presence of nearby Early Devonian wetland vegetation, providing food and shelter for various semi−aquatic and other terrestrial arthropods.
An isolated exopod in uncompressed three−dimensional “Orsten”−type preservation from the Cambrian of Australia represents a new species of Marrellomorpha, Austromarrella klausmuelleri gen. et sp. nov. The exopod is composed of at least 17 annuli. Each of the proximal annuli carries a pair of lamellae: one lamella on the lateral side and one on the median side. The distal annuli bear stout spines in the corresponding position instead of lamellae, most likely representing early ontogenetic equivalents of the lamellae. The new find extends the geographical range of the taxon Marrellomorpha. Additionally, it offers a partial view into marrellomorph ontogeny. The occurrence of a marrellomorph fragment in “Orsten”−type preservation provides new palaeo−ecological insights into the possible connections between the “Orsten” biotas and other fossil Lagerstätten. Finding such connections is necessary for understanding the complex ecosystems of early Palaeozoic times.
Three species of bradoriid arthropods from the lower to middle Cambrian transitional interval of Scania, southern Sweden, are described and illustrated: Beyrichona tinea from the top of the traditional lower Cambrian (Gislöv Formation; Ornamentaspis? linnarssoni Zone), and Hipponicharion eos and Alutella sp. from the basal portion of the traditional middle Cambrian (lowermost part of the Alum Shale Formation). The bradoriid fauna compares most closely with others previously described from western and eastern Avalonia (New Brunswick and England). The record of B. tinea suggests a correlation between the “Protolenus Zone” (Hupeolenus Zone) of western Avalonia and the O.? linnarssoni Zone of Scandinavia. Hipponicharion eos appears to be a fairly long−ranging species as it has previously been recorded from upper lower Cambrian or lower middle Cambrian strata in New Brunswick, Poland, and probably Sardinia. The record of H. eos from the lowermost part of the Alum Shale Formation suggests that this largely unfossiliferous interval in the Scanian succession is not younger than the Acadoparadoxides oelandicus Superzone. The genus Alutella has not previously been recorded from the Acado−Baltic Province.
An attempt has been made to locate some of the museums in Europe which hold important collections of insects and mites in amber. Where possible the collections have been documented. Some of the arthropods from UK collections have been photographed and documented in more detail.
A highly spinose fragment of a possibly raptorial appendage from the Arenig (Early Ordovician) of the Upper Fezouata Formation north of Zagora, southeastern Morocco is described as the arthropod Pseudoangustidontus duplospineus gen. et sp. nov. The single fragmentary specimen displays a unique morphology, carrying at least 39 pairs of spines (i.e., 78 spines) of very regularly alternating lengths. Pseudoangustidontus gen. nov. shows some similarities to a number of spinose arthropod appendages and appendage parts, most notably to the spine−bearing podomeres of the third prosomal appendage of megalograptid eurypterids and the problematic and incompletely known genus Angustidontus. However, megalograptids and Angustidontus both have a lower spine count, while the latter also carries only a single row of spines. Because no known arthropod displays a morphology closely comparable to that of Pseudoangustidontus gen. nov., the affinities of the new fossil within Arthropoda remain uncertain.
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Zhenghecaris shankouensis gen. et sp. nov. is one of the largest “bivalved” arthropods of the Lower Cambrian Maotianshan Shale fauna. Its non−mineralized carapace was dome−like, laterally compressed, armed with rostral features, and probably enclosed the entire body of the animal. Zhenghecaris was provided with elliptical stalked lateral eyes. The carapace design, external ornament and visual organs of Zhenghecaris suggest affinities with the Thylacocephala, an extinct (Lower Silurian to Upper Cretaceous) group of enigmatic arthropods whose origins remain poorly understood. The bivalved arthropodsIsoxys and Tuzoia (Lower and Middle Cambrian) are two other potential thylacocephalan candidates making this group of arthropods a possible new component of Cambrian marine communities. Zhenghecaris, Isoxys, and Tuzoia are interpreted as nektonic animals that probably inhabited the lower level of the water column in shallow shelf settings at depths of perhaps 100–150 m or less. Their feeding mode either in the water column (e.g., mesozooplankton) or on the substrate (e.g., small epibenthos, detritus) is uncertain, although some of these arthropods were possibly mid−water predators (e.g., Isoxys with raptorial appendages).
Viruses are known to be agents of important diseases of Insecta and Acarina, and many vertebrate and plant viruses have arthropods as propagative vectors. There is fossil evidence of arthropod pathogens for some micro-organisms, but not for viruses. Isolated virions would be hard to detect but, in fossil material, it could be easier to find traces of virus infection, mainly virus-induced cellular structures (VICS), easily recognisable by electron microscopy, such as virions encapsulated in protein occlusion bodies, aggregates of membrane-bounded virus particles and crystalline arrays of numerous virus particles. The following main taxa of viruses that multiply in arthropods are discussed both for some of their evolutionary aspects and for the VICS they cause in arthropods: A. dsDNA Poxviridae, Asfarviridae, Baculoviridae, Iridoviridae, Polydnaviridae and Ascoviridae, infecting mainly Lepidoptera, Hymenoptera, Coleoptera, Diptera and Acarina; B. ssDNA Parvoviridae, infecting mainly Diptera and Lepidoptera; C. dsRNA Reoviridae and Birnaviridae, infecting mainly Diptera, Hymenoptera and Acarina, and plant viruses also multiplying in Hemiptera; D. Amb.-ssRNA Bunyaviridae and Tenuivirus, that multiply in Diptera and Hemiptera (animal viruses) and in Thysanoptera and Hemiptera (plant viruses); E. -ssRNA Rhabdoviridae, multiplying in Diptera and Acarina (vertebrate viruses), and mainly in Hemiptera (plant viruses); F. +ssRNA Togaviridae, Nodaviridae, Tetraviridae, Flaviviridae and Picornaviridae, multiplying mainly in Lepidoptera, Hymenoptera, Diptera and Acarina (animal viruses), and in Hemiptera the plant Marafiviruses; G. RNA-RT Metaviridae and Pseudoviridae, multiplying in Diptera and Lepidoptera. Fossil arthropods included in amber or similar material derived from plant resins, that had the ultrastructure preserved, would be the best material for viral palaeontological studies. Volcanic ash and carbon deposits could also give good preservation.
Studies were conducted in north-east Poland during the period from October 1987 to February 1993 - 570 cervids were studied (roe-deer, red deer, sika deer, fallow deer and moose). Thirteen species of ectoparasites were noted, the most frequent included Damalinia meyeri, Lipoptena cervi, Dermacentor reticulatus, Ixodes ricinus, and Chorioptes texanus, found only for the second time in Poland. The moderate number of arthropods noted included Solenopotes capreoli, S. burmeisteri and also Demodex kutzeri. The greatest infestation in the majority of hosts was noted on the bulls, that on females and young being lower but similar.
Rocks have been overlooked as subjects for ecological study. However, the system of narrow and deep vertical spaces (gorges, crevices, abysses) in sandstone rocks supports a highly diverse mosaic of habitats. The patterns of air temperatures and the assemblages of arthropods were studied along the environmental gradient in the Poseidon Sandstone Labyrinth within the Adršpašsko-Teplické Skály National Nature Reserve, NE Bohemia, Czech Republic. The labyrinth, developed in Cretaceous sandsones at an altitude of about 600 m, is approximately 740 m long and 550 m wide. It consists of a broken, interconnected network of deep vertical crevices, crevice caves, and talus caves in extensive block accumulations. The total length of the human-accessible underground spaces is estimated to be at least 27 km, the vertical range is 105 m. The annual course of air temperature was monitored on the sun-exposed upper rock margin (max. 26.5°C, min. –7.3°C, mean 6.1°C), as well as in the cold and dark crevice cave (max. 9.6°C, min. –1.9°C, mean 3.7°C). Due to the climatic inversion in the deep vertical spaces, mountain bryophytes and vascular plants occur here. A total of 2285 arthropods belonging to eight taxonomic groups were evaluated; spiders and beetles were the most numerous. We registered 304 species, which colonize the totality of habitats in the labyrinth: cold bottom parts, dark caves, shady rock walls, as well as the sun-exposed upper rock margins. The cold parts of the labyrinth harbour populations of sixteen species of mountain arthropods (beetles, spiders and a harvestman) and five species of arthropods with distributions in tundra or boreal forests, and similar disjunctive habitats in the temperate zone in central Europe (spiders and a mite). The first record of the Arctic predatory mite Rhagidia gelida in central Europe was in the Poseidon Labyrinth in 1986; this species proved to be a bio-indicator of the long-lasting periglacial microclimate in central Europe. Prior to discovery of the spider Sisicus apertus in the Poseidon Labyrinth, it had been recorded in central Europe in the Alps and in the High Tatra Mountains at altitudes of 1150 to 2300 m. At the present time, we consider the Poseidon Sandstone Labyrinth to be a paleorefugium of cold-adapted arthropods.
Acari and Collembola are the dominant groups within the mycophagous arthropods linked to fungal-based food webs in undisturbed soils. Studies on soil microarthropod communities in old, traditional, multifunctional farmland, and studies on secondary succession following marginalization and abandonment of traditional farmland are lacking in Europe. Thus, we studied patterns of microarthropod communities related to different land use regimes in a traditional farm in Western Norway. Soil mesofauna communities were analysed at four sites: site OM – old, herb rich, open hay meadow in traditional use; site F1 – abandoned hay meadow with pollarded trees (first fallow); site F2 – deciduous woodland (abandoned hay meadow with old pollards, heavily overgrown, second fallow); and site RM – restored hay meadow with scattered, newly pollarded trees. The abundance of the taxa varied considerably between habitats (for instance: total microarthropods – from 112.4 ±11.4 to 29.2±3.4, Acari – from 83.9±10.2 to 15.6±1.8 and Oribatida – from 68.6±9.5 to 8.2±1.3 × 10³ m⁻², for OM and RM sites respectively). The abundance of total Acari, total Oribatida, Oribatida adults and juveniles differed significantly between OM-F1, OM-RM, OM-F2 and RM-F2 sites and it was significantly correlated with continuity of land use and/or tree cover. Oribatida was the group with the highest densities and percentage dominance (except RM site). The percent contribution of total Oribatida in Acari abundance was negatively correlated with the percentage of Actinedida. Nine Ptyctimina species, six Nothroidea species and four Uropodina species were detected, but most of them occurred as single individuals. Abundance of three Ptyctimina [Atropacarus (Atropacarus) striculus (C.L. Koch), Phthiracarus ferrugineus (C.L. Koch), P. globosus (C.L. Koch)], and two Uropodina [Trachytes pauperior Berlese and Dinychus perforatus Kramer] species differed significantly between some sites. The percentage similarity (Renkonen index) has a high indicative value for measuring the distance between ecosystems with apparently similar communities of Uropodina. The OM and RM sites differed most and site pairs – F1-F2 and F1-RM were the most similar. The densities of some taxa were about twoor three-fold greater for the F1site than the RM site. Ratios of Acari to Collembola, total Oribatida to Collembola and total Oribatida to Actinedida were highest on OM site (3.2, 2.6, 11.8 respectively) and decreased in the following order: F2>F1>RM (as an example, total Oribatida to Actinedida ratios were 9.8 on F2 site, 6.2 on F1 and 3.1 on RM). These ratios differed significantly between the OM and RM sites. The lowest ratios on RM site are probably an effect of recent disturbance (change of land use) of this site. Our results suggest that soil in OM site, despite constant disturbance during long time (scything, hay raking and sheep grazing), has probably a stable mesofauna community with the highest abundance of Oribatida. Our results have provided new knowledge about ecosystems in traditional farmland and can be used in monitoring programmes of post-arable land.
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