Three-Dimensional Morphological and Mineralogical Characterization of Testate Amebae

  title={Three-Dimensional Morphological and Mineralogical Characterization of Testate Amebae},
  author={Eric Armynot du Ch{\^a}telet and Catherine Noiriel and Maxence Delaine},
  journal={Microscopy and Microanalysis},
  pages={1511 - 1522}
Abstract Testate amebae are unicellular shelled protozoa commonly used as indicators in ecological and paleoecological studies. We explored the potential application of three-dimensional (3D) X-ray micro-tomography used in addition to 2D techniques (environmental scanning electron microscopy, electron probe micro-analysis, and cathodoluminescence) for detailed characterization of agglutinated shells of protozoa. We analyzed four specimens of the aquatic testate ameba Difflugia oblonga… Expand
The mineral composition of the tests of ‘testate amoebae’ (Amoebozoa, Arcellinida): The relative importance of grain availability and grain selection
It is concluded that the testate amoebae select grains according to their size from those available within their immediate environment, while their size seems to be a function of the distance from the source. Expand
Carbonaceous and siliceous Neoproterozoic vase-shaped microfossils (Urucum Formation, Brazil) and the question of early protistan biomineralization
Abstract. Vase-shaped microfossils (VSMs) occur in dolomitic extraclasts of indeterminate provenance within the basal diamictite of the Neoproterozoic Urucum Formation (Jacadigo Group) ofExpand
Multiproxy approach for Holocene paleoenvironmental reconstructions from microorganisms (testate amoebae and foraminifera) and sediment analyses: The infilling of the Loire Valley in Nantes (France)
Foraminifera and testate amoebae are jointly used with sediment characteristics (sediment size, calcium carbonate, C, H, N and S proportions, and clay mineralogy) to reconstruct the Holocene sedimentExpand
The Phanerozoic diversification of silica-cycling testate amoebae and its possible links to changes in terrestrial ecosystems
A novel molecular clock reconstruction for arcellinids is presented and the origin of hyalosphenids is put in the early Carboniferous, suggesting possible links between the evolution of Arcellinid testate amoebae and the expansion of terrestrial habitats rich in organic matter and bioavailable Si. Expand
Agglutination of benthic foraminifera in relation to mesoscale bathymetric features in the abyssal NE Atlantic (Porcupine Abyssal Plain)
Abyssal hills, small topographic features rising above the abyssal seafloor (< 1000 m altitude), have distinct environmental characteristics compared to abyssal plains, notably the presence ofExpand
Application of Peltier Cooling Device in a Variable-Pressure SEM
In environmental monitoring and water protection one has to deal with various hydrated specimens, and therefore, there is a need for scanning electron microscopes which are suited for hydratedExpand
Cellular intelligence: Microphenomenology and the realities of being.
  • B. Ford
  • Computer Science, Medicine
  • Progress in biophysics and molecular biology
  • 2017
It is argued here that the essential processes of cognition, response and decision-making inherent in living cells transcend conventional modelling, and microscopic studies of organisms reveal a level of cellular intelligence that is unrecognized by science and is not amenable to computer analysis. Expand
Quantum-Like Issues at Nature’s Ecological Scale (the Scale of Organisms and Their Environments)
A theory of perception for all organisms encounters two quantum-like issues. Issue 1 is the there not here enigma or outness problem. For example, given visual entities here (e.g., in the sensoryExpand
Foraminiferal paleoecology of Sarvak Formation (Cenomanian) in the east of Shiraz, interior Fars, Zagros Basin, Iran
The Sarvak Formation is a thick carbonate sequence of Cenomanian age that has been deposited in a foreland basin across the Zagros Basin. Sarvak Formation is the main petroleum reservoir rock in theExpand


Biostratigraphic and palaeoenvironmental applications of testate amoebae
Current and recently developed applications of testate amoebae analysis to biostratigraphic description of Quaternary sediments and palaeoenvironmental reconstruction are reviewed and the potential for the further exploration and use of the technique is emphasised. Expand
X-ray microanalysis of the mineral components in the scales of an amoeba, Cochliopodium sp. (Testacea)
SummaryMineral components of the scales in an amoeba, Cochliopodium sp., were examined by energy-dispersive X-ray microanalysis. The precipitates in potassium antimonate-treated material detectedExpand
Shell structure in Difflugia Lobostoma observed by scanning and transmission electron microscopy.
Observations by scanning and transmission electron microscopy provide information about shells of Difflugia lobostoma which suggests a complex activity in shell construction and suggests that shell structure may be species specific. Expand
Influence of sediment grain size and mineralogy on testate amoebae test construction Influence de la taille et mineralogie des grains du sediment sur la construction des theques des thecamœbiens
This study analyses both the grain size and mineralogical assemblage of tests of common species belonging to the genus Centropyxis and Difflugia and concludes that grain size is a limiting factor for test construction, whereas mineral composition is not. Expand
Carbonate Grain-Size Distribution in Hemipelagic Sediments from a Laser Particle Sizer: RESEARCH METHODS PAPERS
ABSTRACT Laser grain-sizer instruments provide the opportunity to study the grain size distribution of sediments across a wide size range in a short time. Automatic measurements can therefore beExpand
Carbonate Grain-Size Distribution in Hemipelagic Sediments from a Laser Particle Sizer
Laser grain-sizer instruments provide the opportunity to study the grain size distribution of sediments across a wide size range in a short time. Automatic measurements can therefore be made, on aExpand
Soil protozoa as bioindicators: pros and cons, methods, diversity, representative examples
Ciliates and, especially, testate amoebae, whose abundance and diversity can be reliably estimated in simple soil suspensions, should be preferred in environmental studies and should be given preference over dilution culture techniques, which are beset with uncontrollable deficiencies. Expand
Chironomids (Diptera) in river floodplains: their status and potential use for palaeoenvironmental reconstruction purposes
The conclusions drawn from the present findings on subfossil chironomid analysis in river systems show that these can provide a useful tool for palaeoenvironmental reconstruction purposes. Expand
Classification of the Amphiboles
The current IMA-approved classification scheme for amphiboles is described, some shortcomings of the current scheme are discussed, and some of the features that may be considered as desirable in any new scheme of amphibole classification that may emerge in the future are discussed. Expand
Die Schalenbildung bei Difflugia oviformis (Rhizopoda, Testacea)
  • H. Netzel
  • Biology
  • Zeitschrift für Zellforschung und Mikroskopische Anatomie
  • 2004
The surface of the early anlage first appears to be wrinkled or undulated—the elements being distributed in several discontinuous layers—but becomes smooth towards the end of morphogenesis, as soon as the idiosomes are arranged and glued together in a random mosaic pattern to form a single, continuous stratum. Expand