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Four new species of the ostracods of the family Beyrichiacea from the marly limestones of the Upper Givetian (= Stringocephalus burtini Beds) of the SE part of the Holy Cross Mts have been described and assigned to the genera Kozlowskiella (Přibyl), Reversoscapha Rozhdestvenskaja, Welleria Ulrich & Bassler and Welleriella Abushik. The ostracods, trilobits, Conchostraca and Charophyta are found in the marly limestone intercalations in the stromatoporoid-coral limestone series.
A new genus Mojczella, including three new species: Mojczella polonica sp. n., M. jaanussoni sp. n. and M. sanctacrucensis sp. n. have been described from the Lower and Middle Ordovician from Mójcza in the Świętokrzyskie Mts. The stratigraphical range, geographical distribution and relationships of the new genus are discussed.
Colonies of boring ctenostome bryozoans and microborings of “fungi” that occur in the Early Devonian (Lochkovian, ~416 Ma) of Podolia, western Ukraine, have soft−tissue preserved by phosphatization. These comprise exceptional three−dimensional body walls of feeding zooids with probable parietal muscles inserted on the cystid wall, and setigerous collars twisted within the vestibulum. The presence of collars in this Early Devonian ctenostomes proves the existence of this feature for more than 416 Ma of ctenostome evolution. Phosphatized remains of the zooid walls are interpreted as relicts of the originally chitinous cystid walls. This is the first record of soft−tissue fossilization in a boring bryozoan. The presence of cavities (specialized heterozooids), empty or filled with laminated calcium phosphate, is also documented in bryozoans for the first time. These cavities are interpreted as “store−rooms” in which the bryozoans accumulated nutrients. The new taxon, Podoliapora doroshevi gen. et sp. nov. is described. In additional, phosphatised fungi−like endoliths co−occur with bryozoans.
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.
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.
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The ostracod valves from Middle Ordovician limestones, the profile of Mójcza, Holy Cross Mts., Poland, have been found to contain a new morphologic type of microbial borings. These are phosphate fillings of tunnels (9—13 µm in diameter) parallel to the valve surface, with bottle-like terminal swellings. They occur mainly in big and smooth ostracod valves.
Twelve species of the genus Discocydina Gümbel, 1868 from a series of dolomitic sandstones and siltstones are described, along with Upper Lutetian and Lower Bartonian organodetrital limestones from the area of Mt. Hruby Regiel in the Tatra Mts. The mode of life and environment of discocyclines are dealt with and burrows of crabs encased by tests of discocyclines described.
Opisano dwa gatunki małych promienistych numulitów, Nummulites orbignyi (Galeotti) i Nummulites concinnus Jarzeva, z górno eoceńskich piasków glaukonitowych północno-zachodniej Polski. Zrewidowano dotychczasowe poglądy na temat występowania numulitów na Niżu Polskim, oraz przeprowadzono próbę korelacji występowania tych numulitów z obszarem północno-zachodniej Europy i Ukrainy.
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.
Thirty-one species of silicified foraminifers, representing thirteen genera, are described from the uppermost Devonian deposits of Kowala locality, Świętokrzyskie (Holy Cross) Mts. Two species are new: Hyperammina eickhoffi sp. n. and Toiypammina minuta sp. n. Most species belong to the agglutinating genera Hyperammina, Thurammina and Tolypammina. The stratigraphic position of this fauna coresponds to the upper part of the ostracod hemisphaerica-dichotoma Zone and conodont costatus Zones.
The prominent external ornamentation of the entomozoacean shells arises from the thin outer layer. The much thicker and structurally complicated inner layer is rarely well preserved. Three microstructural types of the inner layer are recognized: (1) poorly calcified with residual remnants of the original organic matter, (2) better calcified with oval in transverse section cavities that possibly were originally empty, or filled with an organic matter, longitudinal canals, (3) heavily calcified, in some specimens with sparite-filled remnants of cavities, which may represent only artifacts of recrystallization. The outer layer may correspond to the epicuticle and the inner layer to the endocuticle of Recent ostracodes. A hinge, slight left over right valve overlap, and marginal sculpture are identified for the first time in Famennian entomozoaceans. The mode of life remain unknown. Richterina (Fossirichterina) uffenordeae sp. n. and R. (R.) goodayi sp. n. are proposed.
Late Frasnian–Early Famennian entomozoacean ostracod assemblages from the Płucki section in the Holy Cross Mountains were studied to establish the effect of the “Kellwasser bio−event” on the planktonic biodiversity and faunal content. The composition of ostracod assemblages changes from a moderately diverse (10 species) Entomoprimitia–Richterina– Nehdentomis–Nandania dominated “background” assemblage characterising a pre−event interval, to an Entomoprimitia−assemblage during the event interval, and finally to a Franklinella−dominated post−event assemblage in the Middle Palmatolepis triangularis conodont Zone. The Frasnian–Famennian extinction caused substantial losses among entomozoacean lineages. In the Płucki section it occurred in two closely spaced steps within the Palmatolepis linguiformis conodont Zone. The first step, at the base of the dark cephalopod limestone (Upper Kellwasser Horizon), reduced the abundance and the species diversity of entomozoaceans to only two Entomoprimitia species. The vacant niche was then filled by the new, immigrant species Entomoprimitia (Entomoprimitia) kayseri which is dominant in the Upper Kellwasser interval. All these species were lost at the second step within the Upper Kellwasser Horizon. The entomozoaceans remained virtually absent during a long time interval between the end−Frasnian crisis and the Middle Pa. triangularis Zone. They reappear as new species from refugia lineages (Franklinella, Nehdentomis) and became widespread, indicating favourable ecological conditions. Some 13 species have been identified and assigned to seven genera. Rabienella? lagowiensis sp. nov. is proposed.
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An assemblage of well−preserved spinicaudatan crustaceans (“conchostracans”) is described from lacustrine late Carnian claystone at Krasiejów in southwestern Poland. Their shell microstructure is similar to that in extant spinicaudatans. Five species identified there are assigned to the genera Laxitextella, Menucoestheria (first record in the European Triassic), and Menucoestheria bocki sp. nov. and Krasiestheria parvula gen. et sp. nov. are erected. Specimens of Laxitextella laxitexta are the most abundant, comprising nearly half of the assemblage, those of Menucoestheria bocki one quarter, Laxitextella sp. A, Menucoestheria? sp., and Krasiestheria parvula form a minor component. Their ecological setting was probably similar to Recent relatives: temporary ponds of fresh water. The Late Triassic fauna in the German part of the same basin is closely similar to that in Poland. In Europe, the stratigraphic range of Laxitextella laxitexta is limited to the Middle Keuper (middle–late Carnian).
Ostracods from the Arche quarry at Frasnes are analysed. Twenty−seven species are recognised in the Chalon Member and in the very base of the Arche Member of the Moulin Liénaux Formation. Three new species: Scrobicula gracilis, Microcheilinella archensis, and Bairdia (Rectobairdia) chalonensis, and one subspecies Plagionephrodes laqueus praelaqueus, are proposed. The fauna is in the Favulella lecomptei Zone based on metacopid ostracods and belongs to the Eifelian Mega−Assemblage. Ostracods are indicative of a regressive trend from a moderately deep poorly oxygenated marine environment below fair weather wave base to very shallow well oxygenated and agitated environments. Comparison of the ostracod fauna present in the Arche quarry with faunas described from the Frasnes railway section and from the Lion quarry shows that ostracods did not suffer a crisis during the Palmatolepis punctata Conodont Zone and close to the Early–Middle Frasnian boundary.
Ostracods from Admiralty Bay on King George Island (South Shetland Islands) represent 29 podocopid species, belonging to 19 genera, one cladocopid and six myodocopid species. They were recovered from Recent marine and/or glacio-marine sediment samples from water depths of up to 520 m. These ostracods constitute a variable assemblage, which is overall typical for the Antarctic environment. Shallow-water assemblages tend to be more variable in terms of frequencies and species richness than deep-water assemblages. The later are low in numbers and remain relatively high diversities. Overall, no linear relation between ostracod assemblage-composition and environmental features analyzed was recognized.
Excellently preserved ostracods from large blocks of the late Callovian (Quenstedtoceras lamberti Zone) black clays occurring within glacial drift near Łuków, eastern Poland, are described. Unlike coeval faunas from other localities in Poland, the Łuków ammonite assemblage exhibits boreal affinities. The ostracod fauna broadly resembles those of the British Isles and northwestern Germany, there are also some similarites to Central Russia and northwestern Poland. Seventeen ostracod species are reported, and Schuleridea (Eoschuleridea) lukoviensis sp. n. is proposed. The ostracod assemblage is dominated by large number of specimens of Nophrecythere and Schuleridea (Eoschuleridea). The ostracods are of late Callovian age as indicated by the presence of Nophrecythere triebeli, Progonocythere callovica and advanced evolutionary forms of Nophrecythere intermedia and Terquemula lutzei. The most probable source of the Łuków clay blocks seems to be from the bed of the Baltic Sea north of Gdańsk.
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