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1

Modelowanie morfogenezy szkieletu otwornic

100%
Tyszka J.
Działalność Naukowa PAN. Wybrane Zagadnienia
|
2003
|
tom 16
134-136
2
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The phanerozoic diversity of agglutinated foraminifera: Origination and extinction rates

75%
Kaminski M. A., Setoyama E., Cetean C. G.
Acta Palaeontologica Polonica
|
2010
|
tom 55
|
nr 3
529-539
New diversity curves for agglutinated foraminiferal genera are presented based on the stratigraphic ranges of 764 genera distributed over the 91 Phanerozoic chronostratigraphic subdivisions given in the ICS timescale. The data set for this analysis is based on the stratigraphic ranges of agglutinated genera published in Foraminiferal Genera and their Classification, 218 of which have been modified based upon subsequently published studies and new observations. Additionally, a total of 136 genera have been newly described or reinstated subsequent to the publication of Foraminiferal Genera and their Classification. The revision of stratigraphic ranges is part of the effort by the Grzybowski Foundation’s International Working Group on Foraminiferal Classification to compile a new Catalogue of Agglutinated Foraminiferal Genera. The mean standing diversity of agglutinated foraminiferal genera was compiled by counting the number of boundary crossers rather than the number of genera in each stage. This diversity curve displays a general upward trend throughout the Phanerozoic, punctuated by peaks and troughs of variable magnitude. The curve shows a period of initial radiation from the Early Cambrian to the Early Silurian, followed by a plateau to the Late Permian. The Permian/Triassic and the Triassic/Jurassic boundaries are characterised by small dips in the diversity record. The Jurassic begins with an exponential rise in mean standing diversity that continues to the Cenomanian. The Cenomanian to Holocene record of mean standing diversity is characterised by four peaks and troughs that are roughly in line with the cycles of global climate, with reductions in diversity in the end−Cenomanian, end−Cretaceous, and end−Miocene. Excluding modern values, the Phanerozoic maximum in the number of genera with a fossil record is observed in the Cenomanian, whereas the maximum Phanerozoic mean standing diversity is observed in the Langhian stage of the Miocene. The highest per−capita origination rates are observed in the Hettangian, Dapingian, Pleistocene, and Sheinwoodian (mid−Silurian). Linear regression analysis of the origination rates reveals a decrease towards the Holocene, in agreement with findings of Raup and Sepkoski. The highest per−capita extinction rates are observed in the Messinian, late Silurian (Gorstian), Hirnantian (latest Ordovician), and Maastrichtian. The background extinction rate shows an increasing trend towards the Recent, which is in disagreement with the findings of Raup and Sepkoski. We attribute this apparent discrepancy to the Late Cretaceous to Palaeogene extinctions of shallower−water larger agglutinates and the pull of the end−Miocene extinction event.
3
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Taxonomy, phylogeny, and functional morphology of the foraminiferal genus Involutina

75%
Rigaud S., Blau J., Martini R., Rettori R.
Acta Palaeontologica Polonica
|
2015
|
tom 60
|
nr 1
Early Jurassic aragonitic foraminifers are outstandingly well-preserved in the Marmorea crust, a multiphased ferromanganese layer limiting the Schnöll and Adnet formations (Adnet, Northern Calcareous Alps, Austria). This remarkable preservation, related to the pervasive impregnation of aragonitic tests prior to their recrystallization, allowed observing unknown diagnostic features of the genus Involutina, which typifies the Suborder Involutinina. Thanks to a detailed examination of the Adnet specimens, this paper clarifies the taxonomy, systematic position, and phylogeny of Involutina. A new diagnosis, structural model, and lineage are introduced for the group. Involutina is the direct descendant of Aulotortus and the two taxa probably showed a parallel evolution. As Aulotortus, Involutina presents a high intraspecific variability and its diversity must be revised downward. Current phylogenetic and taxonomic frames of the Suborder Involutinina are firmly questioned as, contrary to previous schemes, the type-genus possesses more than one lamellar deposit per whorl. In Involutina, the height and distribution of papillae on the test surface is not random and probably related to a biological function. We here propose that the papillose lamellae and tube infoldings that characterize representatives of the genus were rudimentary features for light catching and symbiont positioning, respectively.
4

Otwornice bentosowe dzisiejszej Antarktyki Zachodniej

75%
Majewski W.
Kosmos
|
2013
|
tom 62
|
nr 3
5

Contribution of soft-shelled monothalamous taxa to foraminiferal assemblages in the Adriatic Sea

63%
Sabbatini A., Nardelli M. P., Morigi C., Negri A.
Acta Protozoologica
|
2013
|
tom 52
|
nr 3
6

Schellwienia arctica [Fusulinidae] from the Carboniferous-?Permian strata of the Treskelodden Formation, south Spitsbergen

63%
Blazejowski B., Holda-Michalska A., Michalski K.
Polish Polar Research
|
2006
|
tom 27
|
nr 1
91-103
The fusulinid foraminifers of Schellwienia arctica (Schellwien, 1908) have been investigated from Polakkfjellet Mt., south Spitsbergen, and used as biostratigraphic marker for the latest Carboniferous-?earliest Permian strata of the Treskelodden Formation. A series of thin sections enable to investigate the internal structure and growth pattern of individual specimens. The observed variation of growth suggests dynamic environmental conditions at the investigated location and most likely over one-year long life span of this foraminifer.
7
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Recent and some Holocene Foraminifera of the southern Baltic Sea

63%
Brodniewicz I.
Acta Palaeontologica Polonica
|
1965
|
tom 10
|
nr 2
The fauna of the Benthonic Holocene (8 species) and Recent (48 species) Foraminifera of the Southern Baltic Sea has been described, and three new species: Reophax hoeglundi, Reophax mankowskii and Elphidium kozlowskii, have been distinguished. The distribution of the Baltic Foramdnifera has been investigated in correlation with the physico-chemical conditions of the environment, The methods of preparing and handling the samples and their influence on the possibilities of the preservation of the tests of the Foraminifera in the fossil state have been discussed.
8

Experimental chronic exposure of the Foraminifera Pseudotriloculina rotunda to zinc

63%
Nardelli M. P., Sabbatini A., Negri A.
Acta Protozoologica
|
2013
|
tom 52
|
nr 3
9

Benthic foraminiferal communities: distribution and ecology in Admiralty Bay, King George Island, West Antarctica

63%
Majewski W.
Polish Polar Research
|
2005
|
tom 26
|
nr 3
159-214
During the austral summer of 2002/2003 the author collected 38 marine and/or glacio-marine sediment samples from Admiralty Bay on King George Island (South Shetland Islands, West Antarctica). Recent "living" (Rose Bengal stained) and "dead" (subfossil) benthic foraminifera represented by 105 species belonging to 65 genera are recognized in samples from water depths of up to 520 m. They show large spatial variability. Four distinctive foraminiferal zones within the fjord of Admiralty Bay were recognized and analyzed in terms of environmental conditions. The zones are: restricted coves, open inlets, intermediate-, and deep-waters. The major environmental factors, which dictate foraminiferal distribution, are closely related to bathymetry and distance to open sea. Sediment composition and chlorophyll content appear to have minor influence on foraminiferal communities. Most diverse, deep-water faunas dominate water-depths below 200 m, which seems to be the lowest limit of atmospheric and meltwater influence. In waters shallower than 200 m, environmental features, affecting distribution of various benthic foraminiferal assemblages, appear to be sedimentation rate and hydrographic isolation. The results of this study gives promise to use the Admiralty Bay foraminiferal distribution pattern as a paleo- environmental tool for shallow- to intermediate-water Quaternary marine research in fjord settings of the South Shetland Islands.
10

Monothalamous foraminifera from West Spitsbergen fjords, Svalbard: a brief overview

63%
Majewski W., Pawlowski J., Zajaczkowski M.
Polish Polar Research
|
2005
|
tom 26
|
nr 4
269-285
During the 2004 summer season, 14 sediment samples were collected in Kongs- fjorden and Isfjorden, West Spitsbergen, from 6 down to 345 m water-depth (mwd). The samples yielded abundant assemblage of monothalamous foraminifera, belonging to almost 40 morphotypes. Our qualitative (>125µm) and quantitative data (125-500µm) allowed to distinguish three water-depth related assemblages in both Kongsfjorden and Adventfjorden (branch of Isfjorden), indicating that soft-walled monothalamous foraminifera show similar habitat gradation along fjord axis as calcareous and robust agglutinated taxa. Among the monothalamous foraminifera, the subtidal assemblage (6 mwd) was dominated by various unidentified allogromiids. The second, shallow-water assemblage (44-110 mwd) was dominated by Psammophaga sp. 1-3, Hippocrepinella crassa, Hippocrepinella cf. hirudinea, and large Gloiogullmia sp. 2. The deep-water (150-345 mwd) monothalamous assemblage was dominated by Psammophaga sp. 4, pear-shaped Hippocrepina sp., Hippocrepina indivisa, and long Cylindrogullmia sp. 2, as well as large agglutinated species Hyperammina subnodosa with attached Tholosina bulla, Hyperammina fragilis and Lagenammina sp.
11
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Planktonic foraminiferal response to Middle Miocene cooling in the Southern Ocean [ODP Site 747, Kerguelen Plateau]

63%
Majewski W.
Acta Palaeontologica Polonica
|
2010
|
tom 55
|
nr 3
541-560
The response of planktonic foraminifera to changing oceanographic conditions during Middle Miocene Climate Transition (MMCT) ~14 million years ago (Ma) at ODP Site 747 (Kergeulen Plateau) is investigated. Faunal changes are presented in the background of sea surface temperature (SST) estimates and multi−taxon δ18O and δ13C data presented in other studies. Four faunal transitions are distinguished between 15.0 and 12.2 Ma. The first two affected only a limited number of taxa, and do not lead to large−scale assemblage reorganizations. They are only minor assemblage changes within the pre−MMCT fauna. The first (14.5–14.4 Ma) is marked by a reduction in the Globorotalia zealandica plexus in favor of the Globorotalia praescitula plexus, coupled with the first signs of increased seasonality. The second (14.3–14.2 Ma) is characterized by recovery and diversification of the G. zealandica plexus and an increase in Turborotalita quinqueloba in response to further enhanced seasonality. The third faunal transition across the Middle Miocene Shift (MMS) in 18O (13.9–13.8 Ma) affects almost all planktonic foraminifera, leading to dismembering of the pre−MMCT assemblage. These changes were triggered by the SST drop by ~7C, followed by reduced sea−surface salinity following the MMS, which favored the opportunistic Neogloboquadrina continuosa. Its dominance spans the transitional period (13.8–13.2 Ma), during which several planktonic foraminiferal events gradually shaped the post−MMCT assemblage. The fourth faunal threshold took place during the hiatus in the ODP Hole 747A record spanning 13.2–12.5 Ma. It is expressed by the establishment of an assemblage dominated by Globorotalia praescitula and Globigerina bulloides in association with diminishing of the low−salinity surface layer. The two dominant taxa exhibit well−defined morphologies, much different from their earlier relatives. The microperforate foraminifera show relatively few morphological changes, probably due to their morphological conservatism. Their changes are thought to herald the large foraminiferal transformations, especially in case of the third and fourth faunal transition thresholds.
12

Seven reasons why protists make useful bioindicators

63%
Payne R. J.
Acta Protozoologica
|
2013
|
tom 52
|
nr 3
13
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Tracing the signature of various frontal systems in stable isotopes (oxygen and carbon) of the planktonic foraminiferal species Globigerina bulloides in the Southern Ocean (Indian Sector)

63%
Khare N., Chaturvedi S. K.
Oceanologia
|
2012
|
tom 54
|
nr 2
Twenty-five surficial sediment samples, collected on board ORV Sagar Kanya during her 199th and 200th cruises along a north-south transect between latitudes 9.69◦N and 55.01◦S, and longitudes 80◦E and 40◦ E were studied for isotopic variations (values of δ18O and δ13C) of the indicator planktonic species Globigerina bulloides. The results indicate that from latitudes 9.69◦N to 15◦ S both these isotopes (δ18O and δ13C) fluctuated significantly. Between latitudes from around 15◦S to 30–35◦S δ18O values steadily increased, whereas δ13C showed a decreasing trend. However, to the south of latitudes 30–35◦S, both isotope values showed a similar response with a gradual increase up to latitude 50◦S, beyond which δ18O continued to increase while δ13C declined. The characteristic patterns of the values of both isotopes indicates that the signatures of different water masses are associated with various frontal systems and/or water masses across the transect. The signature of the Polar Front at around latitude 50◦S shows the specific response of the isotopic values (δ18O and δ13C) of G. bulloides. Such a response beyond 50◦S latitude is ascribable to the general decrease in the ambient temperature, resulting in a continuous increase in δ18O values, while δ13C values decrease as a result of reduced photosynthesis in regions approaching higher latitudes owing to low light penetration. To further corroborate our results, those of many such transects from geographically distinct regions need to be studied for isotopic variations in the calcareous shells of planktonic foraminiferal species. The results have the potential to be used as a proxy to assess the movement of frontal systems in southern high latitude regions.
14
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Foraminiferal assemblages as palaeoenvironmental bioindicators in Late Jurassic epicontinental platforms: Relation with trophic conditions

63%
Reolid M., Nagy J., Rodriguez-Tovar F. J., Oloriz F.
Acta Palaeontologica Polonica
|
2008
|
tom 53
|
nr 4
Foraminiferal assemblages from the neritic environment reveal the palaeoecological impact of nutrient types in relation to shore distance and sedimentary setting. Comparatively proximal siliciclastic settings from the Boreal Domain (Brora section, Eastern Scotland) were dominated by inner−shelf primary production in the water column or in sea bottom, while in relatively seawards mixed carbonate−siliciclastic settings from the Western Tethys (Prebetic, Southern Spain), nutrients mainly derived from the inner−shelf source. In both settings, benthic foraminiferal assemblages increased in diversity and proportion of epifauna from eutrophic to oligotrophic conditions. The proximal setting example (Brora Brick Clay Mb.) corresponds to Callovian offshore shelf deposits with a high primary productivity, bottom accumulation of organic matter, and a reduced sedimentation rate for siliciclastics. Eutrophic conditions favoured some infaunal foraminifera. Lately, inner shelf to shoreface transition areas (Fascally Siltstone Mb.), show higher sedimentation rates and turbidity, reducing euphotic−zone range depths and primary production, and then deposits with a lower organic matter content (high−mesotrophic conditions). This determined less agglutinated infaunal foraminifera content and increasing calcitic and aragonitic epifauna, and calcitic opportunists (i.e., Lenticulina). The comparatively distal setting of the Oxfordian example (Prebetic) corresponds to: (i) outer−shelf areas with lower nutrient input (relative oligotrophy) and organic matter accumulation on comparatively firmer substrates (lumpy lithofacies group) showing dominance of calcitic epifaunal foraminifera, and (ii) mid−shelf areas with a higher sedimentation rate and nutrient influx (low−mesotrophic conditions) favouring potentially deep infaunal foraminifers in comparatively unconsolidated and nutrient−rich substrates controlled by instable redox boundary (marl−limestone rhythmite lithofacies).
15

Multigene evidence for close evolutionary relations between Gromia and Foraminifera

63%
Longet D., Burki F., Flakowski J., Berney C., Polet S., Fahrni J., Pawlowski J.
Acta Protozoologica
|
2004
|
tom 43
|
nr 4
16

Gymnophrys cometa and Lecythium sp. are core Cercozoa: evolutionary implications

63%
Nikolaev S. I., Berney C., Fahrni J., Mylnikov A. P., Aleshin V. V., Petrov N. B., Pawlowski J.
Acta Protozoologica
|
2003
|
tom 42
|
nr 3
17
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Taxonomy, nomenclature, and evolution of the early schubertellid fusulinids

51%
Davydov V.
Acta Palaeontologica Polonica
|
2011
|
tom 56
|
nr 1
The types of the species belonging to the fusulinid genera Schubertella and Eoschubertella were examined from publications and type collections. Eoschubertella in general possesses all the features of Schubertella and therefore is a junior synonym of the latter. However, the concept of Eoschubertella best describes the genus Schubertina with its type species Schubertina curculi. Schubertina is closely related to the newly established genus Grovesella the concept of which is emended in this paper. Besides Schubertella, Schubertina, and Grovesella, the genera Mesoschubertella, Biwaella are reviewed and three new species, Grovesella nevadensis, Biwaella zhikalyaki, and Biwaella poletaevi, are described. The phylogenetic relationships of all Pennsylvanian–Cisuralian schubertellids are also proposed. Barrel−shaped Grovesella suggested being the very first schubertellid that appears sometimes in the middle–late Bashkirian time. In late Bashkirian it is then developed into ovoid to fusiform Schubertina. The latter genus gave rise into Schubertella in early Moscovian. First Fusiella derived from Schubertella in late Moscovian, Biwaella—in early Gzhelian and Boultonia—in late Gzhelian time. Genus Mesoschubertella also developed from Schubertella at least in Artinskian, but may be in late Sakmarian.
18

Re-discovery of Lieberkuehnia wageneri Claparede et Lachmann, 1859 [Rhizaria, Foraminifera]: taxonomical and morphological studies based on a Slovak population

51%
Mrva M.
Acta Protozoologica
|
2009
|
tom 48
|
nr 2
111-117
19
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Upper Eocene Foraminifera of East Poland and their palaeogeographical meaning

51%
Pozaryska K.
Acta Palaeontologica Polonica
|
1977
|
tom 22
|
nr 1
Foraminiferal assemblage found in Upper Eocene deposits from Siemień (Eastern Poland) includes over 70 species. This assemblage lived in cold shelf waters 80-100 m deep. The foraminifera-bearing deposits may be correlated with lower part of marls of Kiev stage from Ukraine, representing the lower horizon of the Upper Eocene and/or the Middle-Upper Eocene junction beds. Foraminiferal assemblage from Siemień beds is entirely different from that known from the stratotype of the Bartonian. Marine transgression responsible for deposition of Siemień beds presumably reached the area of Poland from the East, utilizing old tectonic frame: Dnepr-Donetz aulacogen and its extensions. This is confirmed by a marked similarity of foraminiferal assemblages as well as composition of heavy minerals present in deposits of Siemień beds.
20

Otwornice i paleosrodowisko formacji badenianu [miocen srodkowy] na obszarze Gornego Slaska

51%
Gonera M.
Studia Naturae
|
2001
|
tom 48
1-211
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