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In subsequent co-infections of Sobolevicanthus gracilis and Fimbriaria czaplinskii an elimination of the majority of specimens of the first species by the next one has been found at the early stage of development. This did not depend on the fact, which species was the first. In concurrent control co-infections of larvae of both species mentioned above developed simultaneously and correctly. It seems to testify the existence of interspecific competition expressed by a peculiar sensibility of larvae at their early stages of development (3rd to 5th day post infection). The longer the larvae of the first species develop the fewer of them become eliminated by the next one.
Morphological variability in lacustrine ostracode Cytherissa lacustris (Sars) expressed as differences in carapace size and nodation pattern as well as the carapace preservation were investigated in five physiographically similar Polish lakes. Individuals of the populations investigated appeared to be considerably longer and less variable than individuals of the previously studied European, Arctic and North-American populations. Considerable variation of the carapace size was found but no visible influence of the selected environmental parameters such as the depth of a lake, grain size and organic matter of sediment could be established. The populations investigated were homogeneous in respect of nodation pattern but in respect of degree of carapace preservation there were recognized two significantly different homogeneous sets of populations.
The Kowala section situated in the southern part of the Holy Cross Mountains represents continuous sedimentation in almost the same facies across the Devonian-Carboniferous (D-C) transition. The D-C boundary has been identified about two meters above the top of the cephalopod nodular limestone with Wocklumeria. In the transitional deposits of the latest Famennian (Prothognathodus kockeli Zone) several faunally distinct units that correspond to relative sea level changes in the area have been identified. Ostracods are abundant in the Kowala sequence. Their assemblages contain well known index species and new ones of the Thuringian and Entomozoacean ecotypes. A total of 15 probably planktonic entomozoaceans, and 64 benthic species have been identified. Healdia shangquii sp. n. and Mauryella polonica sp. n. are proposed. A major change in the ostracod fauna takes place above the limestone with Wocklumeria within the transitional interval represented by clays and claystones with tuffites in its middle part. Thuringian and Entomozoacean ecotype ostracods disappear and are replaced by more shallow water 'exotic' assemblaged ominated by Healdia, Mauryella and Monoceratina species. In the early Tournaisian rocks Thuringian-, Entomozoacean- and Bairdin-type ostracods reappear with some of the same species as before, and with new Carboniferous index taxa.
A sample taken from a detrital limestone lens, presumed to be allochthonous, within the dark coloured argillaceous limestone of the Early Carboniferous Muhua Formation at the Muhua section, Guizhou, South China, yielded numerous, mostly silicified fossils. Ostracodes, which are the most numerous in the sample, were studied by Olempska (1999). Brachiopods and conodonts are described and illustrated in this paper, but other associated fossils are also noted. Among brachiopods the most common are productides, orthotetidines, spiriferides, and orthides. The productoid gen. et sp. indet. 2, Lambdarina sp., and rhynchonelloid gen. et sp. indet. most probably represent new taxa, but are described in open nomenclature because of inadequate material. Conodonts are indicative of late Tournaisian age. The fossil assemblage is represented by phosphatic and silicified remnants, the latter being originally calcitic. The pattern of silicification resulted generally in preservation of skeletal morphology in great details.
Well preserved silicified ostracodes have been found in a presumably allochthonous detrital limestone lens within argillaceous limestones of the Muhua Formation of the Muhua section in Guizhou Province, South China. Some 32 species have been identified and assigned to 24 genera. Houhongfeiella microspinosa gen. et sp. n., Gortanella ruggierii sp. n., Coryellina grammi sp. n., Coryellina advenoides sp. n., Guerichiella coeni sp. n., Knightina jiqiangi sp. n., Hypotetragona? sinica sp. n., Cavellina robinsoni sp. n., Cavellina guizhouensis sp. n., Sulcella jonesi sp. n., Bairdia cheni sp. n., and Bairdiacypris wangi sp. n. are proposed. Similarity at the generic level exists between ostracode faunas of the Early Carboniferous formations of China, Australia, Europe, Asia and North America. Unlike the ostracodes from the underlying nodular limestones of the Wangyou Formation that represent the basinal 'Thuringian ecotype' fauna, the ostracode assemblage of the studied interval belongs to the 'Eifelian ecotype' and is indicative of a well-oxygenated, normal salinity, high-energy shallow-water environment. The term calcified internal rim is proposed for the internal structure developed along the free margin in some palaeocopid ostracodes. It differs from the calcified inner lamella of podocopids mainly in the lack of marginal pore canals, lack of vestibulae and lack of clear separation from the outer lamella.
Late Visean ostracod assemblages from three regions of southern Poland strongly differ in contribution of species and specimens of the three main superfamilies. In the Cracow area, ostracods from the clays of Orlej are basically different from those from the limestone section of Czerna located only ten kilometers eastward but are similar to ostracods from the Lublin region. The kloedenellacean-bairdiacean dominant fauna of Czerna is representative of nearshore conditions, as opposed to the offshore Orlej bairdiacean-kirkbyacean fauna.
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