Wszystkie pola: ostracod - Prolib Integro

Skocz do pozycji: 1.

Tytuł:: An atypical Silurian myodocope ostracod from the Armorican Massif, France
Autorzy:: Perrier, V.
Tematy:: Silurian
paleontology
myodocope ostracod
ostracod
Armorican Massif
France
Arthropoda
Crustacea
Ostracoda
Myodocopa
Entomozoidae
taxonomy; Pokaż więcej
Data publikacji:: 2012
Powiązania:: https://bibliotekanauki.pl/articles/22621.pdf Link otwiera się w nowym oknie
Źródło:: Acta Palaeontologica Polonica; 2012, 57, 2
0567-7920
Pojawia się w:: Acta Palaeontologica Polonica
Opis:: A new myodocope ostracod Sineruga insolita gen. et sp. nov. is herein described from the Armorican Massif (France). Sineruga resembles Silurian myodocopes (i.e., bolbozoids and cypridinids) in having anterior features (thinner carapace) possibly related to vision. On the other hand, it resembles entomozoid ostracods in having a bean−shaped outline along with a deep adductorial sulcus and a simple muscle spot, but lacks their characteristic ribbed ornament. The data available suggest that Sineruga insolita was probably an atypical, non−ribbed member of the entomozoids thus indicating that early entomozoids may have had smooth representatives. Comparisons with other Recent and fossils ostracods show that the presence of a rostrum and/or symmetrical vision related carapace features (i.e., indicating lateral eyes) can be used as diagnostic characters for myodocope ostracods. The position and shape of the dorsal connection and to a lesser extent that of the sulcus and the adductorial muscle scar can be used to discriminate the higher groups of Silurian myodocopes (bolbozoids, cypridinids, and entomozoids).
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 2.

Tytuł:: A boreal ostracod assemblage from the Callovian of the Lukow area, Poland
Autorzy:: Olempska, E
Blaszyk, J.
Tematy:: Nophrecythere intermedia
Terquemula lutzei
ostracod
locality
Polska
Progonocythere callovica
Ostracoda
Baltic Sea
taxonomy
Jurassic
Callovian
Nophrecythere triebeli
Quenstedtoceras lamberti
boreal ostracod
zoogeography
paleontology
ostracod fauna
Lukow area; Pokaż więcej
Data publikacji:: 2001
Powiązania:: https://bibliotekanauki.pl/articles/20975.pdf Link otwiera się w nowym oknie
Źródło:: Acta Palaeontologica Polonica; 2001, 46, 4
0567-7920
Pojawia się w:: Acta Palaeontologica Polonica
Opis:: 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.
Kelowejskie kry glacjalne z okolic Łukowa są słynne z wyjątkowo pięknie zachowanych amonitów o aragonitowych ściankach muszli i pustych fragmokonach (Makowski 1952, 1962; Kulicki 1974, 1979; Dzik 1990) oraz wielu innych grup skamieniałości o niespotykanym stanie zachowania. Makrofauna ta zachowana jest w wapiennych konkrecjach występujących wśród czarnych iłów. W iłach z obrzeża konkrecji oraz w próbkach iłów pobranych z płytkich wierceń (Mizerski & Szamałek 1985), stwierdzono występowanie zespołu małżoraczków liczącego 17 gatunków naleążcych do 16 rodzajów. Utworzono jeden nowy gatunek Schuleridea (Eoschuleridea) lukoviensis. Zespół ten potwierdzający późno kelowejski wiek osadów z których zbudowane są kry łukowskie (poziom Quenstedtoceras lamberti) wykazuje duże podobieństwo do późnokelowejskich zespołów małżoraczkowych z północno-zachodnich Niemiec i Wielkiej Brytanii, w mniejszym stopniu do zespołów małżoraczkowych keloweju Centralnej Rosji i północno-zachodniej Polski. Obszarem źródłowym dla kier łukowskich było prawdopodobnie dno Bałtyku na północ od Gdańska: Skorupki małżoraczków cechują się wyjątkowo dobrym stanem zachowania, pozwalającym na obserwacje wielu cech morfologicznych dotychczas słabo poznanych u kelowejskich małżoraczków z innych obszarów Europy. Zespół małżoraczków z kier łukowskich zdominowany jest przez okazy gatunków rodzaju Nopherythere i Schuleridea (Eoschuleridea).
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 3.

Tytuł:: Phylogeny, palaeoecology, and invasion of non-marine waters by the late Miocene hemicytherid ostracod Tyrrhenocythere from Lake Pannon
Autorzy:: Pipik, R
Tematy:: phylogenesis
Miocene
ostracod
Late Miocene
invasion
Ostracoda
Hemicytherinae
Lake Pannon
hemicytherid ostracod
marginal pore canal
paleoecology
non-marine water
paleontology
Tyrrhenocythere; Pokaż więcej
Data publikacji:: 2007
Powiązania:: https://bibliotekanauki.pl/articles/23418.pdf Link otwiera się w nowym oknie
Źródło:: Acta Palaeontologica Polonica; 2007, 52, 2
0567-7920
Pojawia się w:: Acta Palaeontologica Polonica
Opis:: Species of the ostracod genus Tyrrhenocythere were found in sediments at the western margin of the Danube Basin, dated as Pannonian zone MN9/MN10 of the late Miocene, together with the euryhaline ostracods Euxinocythere, Loxoconcha, Cyprideis, Hemicytheria, Amplocypris, and Paratethyan Candoninae. Sandy and clayey deposits intercalated with lignite seams, as well as the ostracod assemblages, reflect oscillations of Lake Pannon water level and salinity, from freshwater to pliohaline. Tyrrhenocythere most probably evolved by phyletic transformation from Hemicytheria. The hinge and the central muscle scars of Tyrrhenocythere are plesiomorphic characters and the two genera differ in the arrangement of the marginal pore canals (MPC). The transformation of simple, straight and thin MPC in Hemicytheria to polyfurcate MPC in Tyrrhenocythere can be observed in sympatric and contemporaneous populations in Lake Pannon. On the basis of orna− mentation, T. pezinokensis with heavily calcified valves bearing distinct ornamentation could be a descendent of ribbed and heavily calcified Hemicytheria and possibly represents an extinct lineage, while the lightly calcified T. transitivum sp. nov., T. rastislavi sp. nov., and T.sp. 1, and T. sp. 2 are possibly related to reticulated and punctate Hemicytheria. This model assumes that more than one Hemicytheria lineage transformed their arrangement of MPC, and suggests that Tyrrhenocythere is a polyphyletic genus. After the retreat of Lake Pannon, Tyrrhenocythere species immigrated, together with other ostracod and molluscan fauna, into the Dacian Basin and Eastern Paratethys. Later, in the uppermost Messinian, they colonised the western Mediterranean. Late Miocene and Pliocene Tyrrhenocythere are found in brackish or mixed brackish/freshwater taphocoenoses, but the Pleistocene examples also adapted to freshwater/oligohaline lacus− trine environment (Griffiths et al. 2002: 252). While salinity ranges of Tyrrhenocythere have shifted, toward freshwater since the late Miocene, temperature preference did not change. The mean annual air temperature of the Pannonian (15.6–21.7℃) is close to the temperature preference of living Tyrrhenocythere, with mean annual temperature 12 to 16℃. Two new species, T. rastislavi, and T. transitivum are described.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 4.

Tytuł:: Carbon and oxygen isotope variability among foraminifera and ostracod carbonated shells
Autorzy:: Fourel, François
Martineau, François
Emoke Tóth, Emoke
Görög, Agnes
Escarguel, Gilles
Lécuyer, Christophe
Tematy:: stable isotope
foraminifera
ostracod
heterogeneity
single shell analysis; Pokaż więcej
Data publikacji:: 2015
Powiązania:: https://bibliotekanauki.pl/articles/763395.pdf Link otwiera się w nowym oknie
Źródło:: Annales Universitatis Mariae Curie-Skłodowska, sectio AAA – Physica; 2015, 70
0137-6861
Pojawia się w:: Annales Universitatis Mariae Curie-Skłodowska, sectio AAA – Physica
Opis:: This study investigates the effect of biological and environmental inter-individual variability on the meaning of d18O and d13C values acquired on small carbonated shells. First we present data obtained with a MultiPrep automated carbonate system on small sample sizes of a homogeneous carbonate material: Carrara marble. This demonstrates the capacities of the analytical system to reliably run small amounts of carbonates even down to 10 mg. Then we present two data sets obtained on real fossil samples of various size (sensu number of individual organisms) calibrated against the NBS19 carbonate standard. Both datasets evidence a clear trend of between-biological sample standard deviation increase for both d18O and d13C measurements when the number of pooled specimens per sample decreases. According to the results obtained from a systematic study of a geologically homogeneous sample of coeval fossil Elphidium foraminifera, we estimate that there is 95% of chances to reach between-biological sample standard deviation values higher than 1.02‰ (d18O) and 1.45‰ d13C) based on single-cell measurements. Such values are one order of magnitude higher than the instrumental standard deviations associated with these stable isotope ratios. Conversely, a minimum of 35 (d18O) and 44 (d13C) pooled specimens of Elphidium appears necessary to reach a between-sample standard deviation £ 0.25‰ with a probability of 95%. Such biological intrinsic and irreducible variability between coeval individuals, and thus samples, clearly questions the interest for single-cell analyses, more precisely, for coastal marine species, such as Elphidium, subject to many environmental changes during their life-time. Indeed, strong variations in salinity or temperature, as well as biogenic fractionation, could influence the isotopic composition of an individual specimen. Results might be less problematic for an average community including several tests. This paper underlines uncertainties linked to specific environments in which selected organisms live, especially for paleoceanographic or paleoclimatic reconstruction purposes where secular oxygen and carbon isotope variations typically range from 0.5 to 1.5‰.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 5.

Tytuł:: Benthic ostracods from the Early-Middle Frasnian transition in the north-western East European Platform, Russia
Autorzy:: Evdokimova, I O
Tematy:: benthic ostracod
ostracod
Early-Middle Frasnian
Frasnian
paleontology
East European Platform
Russia
Ostracoda
Main Devonian Field; Pokaż więcej
Data publikacji:: 2006
Powiązania:: https://bibliotekanauki.pl/articles/21796.pdf Link otwiera się w nowym oknie
Źródło:: Acta Palaeontologica Polonica; 2006, 51, 4; 773-778
0567-7920
Pojawia się w:: Acta Palaeontologica Polonica
Opis:: Pronounced changes in benthic ostracod associations in the north−west part of the East European Platform, across the Early–Middle Frasnian (Devonian) transition, track a marine transgression event. More than 80 ostracod species belonging to the Eifelian Mega−Assemblage were recorded. Cavellinidae and Acratiidae generally dominate the Early Frasnian Sargaevo Horizon. Middle Frasnian ostracod associations of the Semiluki Horizon are more diverse and are characterised by different dominant both geographically and stratigraphically, resulting from significant palaeo−basin bottom relief and benthic biotope differentiation. The ostracod associations are indicative of very shallow, well oxygenated semi−restricted epeiric environment, with occasional marine influence, alternating with short periods of open shelf conditions. The relative abundance of ostracod species in the different associations, and faunal diversity indices, show considerable variations throughout the Early–Middle Frasnian, and suggest a less restricted position within an intra−platform setting in the Middle Frasnian, relative to a more restricted ostracod habitat in the Early Frasnian. The succession of Early–Middle Frasnian micro−benthic associations within the Main Devonian Field seems to be of a regional scale, and resulted from a marine regression−transgression couplet, corresponding to eustatic cycles IIb–IIc. This was paired with synsedimentary tectonic subsidence in adjacent areas of the north−east East European Platform, progressively improving marine water circulation in the extremely shallow−water shelf seas.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 6.

Tytuł:: Ordovician ostracods from East Central Iran
Autorzy:: Ghobadi Pour, M.
Williams, M.
Vannier, J.
Meidla, T.
Popov, L.E.
Tematy:: geographic setting
Iran
Ordovician
Ostracoda
Shirgesht Formation
brachiopod
geological setting
ostracod
paleontology
trilobite
systematics
ostracod fauna
biogeography
stratigraphy; Pokaż więcej
Data publikacji:: 2006
Powiązania:: https://bibliotekanauki.pl/articles/22059.pdf Link otwiera się w nowym oknie
Źródło:: Acta Palaeontologica Polonica; 2006, 51, 3
0567-7920
Pojawia się w:: Acta Palaeontologica Polonica
Opis:: Ordovician ostracods are described for the first time from Iran, enhancing the record of this group from the Lower Palaeozoic of the Middle East. The ostracods occur in the Shirgesht Formation, in the east central part of the country, and comprise Ogmoopsis achaemenid sp. nov., Cerninella aryana sp. nov., Ordovizona amyitisae sp. nov., cf. Aechmina? ventadorni, Vogdesella sp., and podocope taxa tentatively identified as species of Longiscula, Pullvillites, and Rectella. These taxa were hitherto unknown from this region. The ostracod−bearing interval is associated with trilobites (Neseuretinus) and brachiopods (Nicolella) that suggest a late Middle Ordovician age. Although the ostracod fauna is small, it demonstrates biogeographical links at genus−level, and possibly at species−level, with the fauna of the late Middle Ordovician Travesout Formation of western France, which also lay in a peri−Gondwanan palaeogeographical setting. It also suggests the potential use of some ostracods as stratigraphical tools for correlating Ordovician rock successions between Europe and the Middle East.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 7.

Tytuł:: The Late Devonian Upper Kellwasser Event and entomozoacean ostracods in the Holy Cross Mountains, Poland
Autorzy:: Olempska, E
Tematy:: ostracod
Polska
entomozoacean ostracod
Ostracoda
Upper Kellwasser Event
paleoenvironment
Famennian
stratigraphy
Frasnian
Late Devonian
Devonian
Entomozoacea
extinction
Holy Cross Mountains
paleontology; Pokaż więcej
Data publikacji:: 2002
Powiązania:: https://bibliotekanauki.pl/articles/20081.pdf Link otwiera się w nowym oknie
Źródło:: Acta Palaeontologica Polonica; 2002, 47, 2
0567-7920
Pojawia się w:: Acta Palaeontologica Polonica
Opis:: 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.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 8.

Tytuł:: Endolithic microorganisms in Ordovician ostracod valves
Endolityczne organizmy w skorupkach ordowickich małżoraczków
Autorzy:: Olempska, E.
Data publikacji:: 1986
Powiązania:: https://bibliotekanauki.pl/articles/21021.pdf Link otwiera się w nowym oknie
Źródło:: Acta Palaeontologica Polonica; 1986, 31, 3-4
0567-7920
Pojawia się w:: Acta Palaeontologica Polonica
Opis:: 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.
W skorupkach małżoraczków ordowickich z profilu Mójczy w Górach Świętokrzyskich stwierdzono obecność długich, cienkich rurek, będących fosforanowymi wyściółkami tuneli wykonanych przez mikroorganizmy borujące. Są to cienkie rurki o średnicy 9—13 µm, równoległe do powierzchni skorupek małżoraczków, zakończone nieregularnymi lub buteleczkowatymi rozszerzeniami o średnicy 25—40 µm. Z uwagi na średnicę rurek, jej pewną zmienność w poszczególnych rurkach, brak rozgałęzień, wydaje się, że formy te bardziej zbliżone są do form uważanych przez większość badaczy za powstałe w wyniku działalności borujących alg niż grzybów. Od większości ilustrowanych endolitycznych mikro-drążeń opisane formy różni obecność buteleczkowatych rozszerzeń na końcach rurek. W skorupkach ordowickich małżoraczków mikro-drążenia występują najczęściej w skorupkach różnych gatunków podokopidów o dość dużych, około 1 mm i większych, gładkich skorupkach. W skorupkach o bogatszej rzeźbie powierzchni spotyka się je rzadko, sporadycznie występują w małych skorupkach o długości poniżej 1 mm. Praca została wykonana w ramach problemu MR II 6.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 9.

Tytuł:: Fractal analysis of ostracod shell variability: A comparison with geometric and classic morphometrics
Autorzy:: Aiello, G
Barattolo, F.
Barra, D.
Fiorito, G.
Mazzarella, A.
Raia, P.
Viola, R.
Tematy:: fractal analysis
variability
statistical method
systematics
Krithe compressa
ostracod
shell
Ostracoda
morphometry
morphological variability
Krithe iniqua
paleontology; Pokaż więcej
Data publikacji:: 2007
Powiązania:: https://bibliotekanauki.pl/articles/22918.pdf Link otwiera się w nowym oknie
Źródło:: Acta Palaeontologica Polonica; 2007, 52, 3
0567-7920
Pojawia się w:: Acta Palaeontologica Polonica
Opis:: Two statistical methods, fractal geometry and geometric morphometrics, are tested for their applicability to ostracod systematics. For this comparison, two morphologically similar ostracod species (Krithe compressa and Krithe iniqua) whose genus−level systematics is still incompletely resolved, are selected. Twenty−nine right valves of each species were collected from the upper Pliocene samples at the Monte San Nicola section in southern Italy. Statistical analyses (MANOVA on morphometric shape variables, and D values) were utilized to test if geometric morphometrics and fractal analysis are appropriate into discriminating between the two species. Both methods succeeded in distinguishing the species statistically. The fractal analysis of the two ostracod species shows D values centered on 1.31±0.02 for Krithe iniqua and on 1.40±0.02 for Krithe compressa. Geometric morphometric analysis indicates significant differences between the two species and allows studying intra−populational variability as well as. The most variable traits indicated by geometric morphometrics are vestibular area and posterior outline of the shell, indicating that these traits are the most relevant for the systematics of the species analyzed. Both fractal geometry and geometric morphometrics provide a measure of population variability. Fractal analysis has the advantage of being free from any subjectivity in the selection of characters and could be most appropriate to use for analysis of complex ornamentation for systematic purposes. However, a possible advantage of geometric morphometrics over fractal analysis is its ability to indicate where statistically significant variations in shape occur on the shell.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 10.

Tytuł:: Crinoid and ostracod succesion within the Early-Middle Frasnian interval in the Wietrznia quarry, Holy Cross Mountains, Poland
Autorzy:: Gluchowski, E
Casier, J.G.
Olempska, E.
Tematy:: paleontology
crinoid succession
ostracod succesion
Early-Middle Frasnian
Frasnian
Wietrznia quarry
Holy Cross Mountains
Polska
Crinoidea
Ostracoda
Palmatolepis transitans
Palmatolepis punctata; Pokaż więcej
Data publikacji:: 2006
Powiązania:: https://bibliotekanauki.pl/articles/20148.pdf Link otwiera się w nowym oknie
Źródło:: Acta Palaeontologica Polonica; 2006, 51, 4; 695-706
0567-7920
Pojawia się w:: Acta Palaeontologica Polonica
Opis:: Early–Middle Frasnian ostracods and crinoids from Wietrznia in the Northern Kielce subregion of the Holy Cross area were analyzed. Twenty three ostracod species assigned to thirteen named genera, as well as eighteen crinoid species including the representatives of fifteen stem−based taxa were distinguished. For most of the species open nomenclature is applied. The composition of ostracod assemblage changes from moderately diverse in the lower part of the Palmatolepis transitans Zone to poorly diverse in its higher part. Lack of ostracods in the uppermost part of the Pa. transitans Zone and in the Palmatolepis punctata Zone is noted. The crinoid distribution pattern comprises the interval of relatively high diversity, interrupted in the uppermost part of the Pa. transitans Zone, and the interval of temporary recovery in the lower Pa. punctata Zone. Such distribution patterns point to deterioration of environmental conditions across the Early–Middle Frasnian transition, coinciding with a large−scale C−isotopic perturbation superimposed on intermittent, two−step eustatic sea level rise. On the other hand, impoverished, surviving crinoid faunas and absence of ostracods in the Pa. punctata Zone indicate the overall long−term deterioration of life conditions through the major C−isotope anomaly time span. However, this may also result from synsedimentary tectonic pulses, causing block movements and large−scale resedimentation phenomena on the northern slope of the Dyminy Reef during the basal Middle Frasnian sea level rise.
Dostawca treści:: Biblioteka Nauki

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