The mineral composition of the tests of ‘testate amoebae’ (Amoebozoa, Arcellinida): The relative importance of grain availability and grain selection

  title={The mineral composition of the tests of ‘testate amoebae’ (Amoebozoa, Arcellinida): The relative importance of grain availability and grain selection},
  author={Eric Ch{\^a}telet and Nadine Bernard and Maxence Delaine and Jean Luc Potdevin and Daniel Gilbert},
  journal={Revue de Micropal{\'e}ontologie},
Nine peatlands were selected according to their various geological setting in the eastern part of France. The diversity of mineral particles, including xenosomes (agglutinated particles) and idiosomes (secreted particles), were analysed, together with associated morphological characteristics, for 7 species of ‘testate amoeba’ (order Arcellinida). The combined use of an Environmental Scanning Electron Microscope equipped with an EDS device and microprobe analyses is suitable for conducting an… Expand
Origin and diversity of testate amoebae shell composition: Example of Bullinularia indica living in Sphagnum capillifolium.
The shell content of 38 Bullinularia indica individuals, a single xenosomic testate amoeba species living in Sphagnum capillifolium, was analysed by scanning electron microscope (SEM) coupled with X-ray spectroscopy and showed high diversities of mineral, organic, and biomineral grains, which confirms their capability to recycle xenosomes. Expand
Cinderella's helping pigeons of the microbial world: The potential of testate amoebae for identifying cryptotephra.
This work analyzed by X-ray Spectrometry the mineral signature of tephra from the 2011 Puyehue-Cordon Caulle Volcanic Complex (Chile) eruption ash fallout and compared it to that of the shells of 51 individual testate amoebae from 13 samples collected at different distances from the active vent. Expand
PROTOZOOLOGICA Chlorophyll-a and Suspended Inorganic Material Affecting the Shell Traits of Testate Amoebae Community
Shell composition is considered an important functional trait in testate amoebae community. Differences in the composition of shells may represent adaptations of these organisms to changes in theExpand
Ecological drivers of testate amoeba diversity in tropical water bodies of central Mexico
It is demonstrated that testate amoebae in the water bodies of central Mexico could reveal the presence of environmental stress, and Cucurbitella tricuspis and the Difflugia protaeiformis strain “acuminata” have similar ecological preferences to those reported previously for temperate lakes. Expand
The oldest skeletal macroscopic organism Palaeopascichnus linearis
Abstract The existing problems regarding the phylogenetic resolution of Ediacaran macroscopic organisms stem from a failure to factor-in the information captured through different ‘taphonomicExpand
Testate amoeba records indicate regional 20th‐century lowering of water tables in ombrotrophic peatlands in central‐northern Alberta, Canada
It is suggested that recent apparent drying of peatlands, which may only be reconstructed by appropriate indicators combined with high chronological control, may affect vulnerability to future burning and promote emissions of CO2. Expand
Biologically agglutinated eukaryotic microfossil from Cryogenian cap carbonates
The discovery of new, mineral-rich microfossil assemblages in microbially laminated and other fine-grained facies of Cryogenian cap carbonates from multiple localities on different palaeocontinents demonstrates that agglutinating eukaryotes were widespread in carbonate-dominated marine environments in the aftermath of the Sturtian glaciation. Expand
Leaf Litter Chemistry Drives the Structure and Composition of Soil Testate Amoeba Communities in a Tropical Montane Rainforest of the Ecuadorian Andes
The data show that leaf litter chemistry overrides leaf litter richness in structuring testate amoeba communities, and high litter nitrogen and low lignin concentrations are indicators of high litter quality for testateAmoebae density and species richness. Expand
Micro et nanoanalyses des microfossiles du Protérozoïque et de tapis microbiens fossiles
L’etude de la matiere organique des microfossiles et tapis microbiens preserves dans les roches precambriennes est cruciale pour comprendre l’evolution de la vie precambrienne. Des techniques deExpand


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
Three-Dimensional Morphological and Mineralogical Characterization of Testate Amebae
3D X-ray micro-tomography data shows that D. oblonga is able to selectively pick up the small size fraction of the sediment with a preference for low-density silicates close to quartz density, suggesting the existence of a physical limit to grain size used for building the shell. Expand
Potential implications of differential preservation of testate amoeba shells for paleoenvironmental reconstruction in peatlands
The results show that differential shell preservation has little impact on paleohydrological reconstruction from Sphagnum-dominated peatlands, and further work is clearly needed to assess the potential of testate amoebae for paleoecological studies of minerotrophic peatland studies. Expand
Silica and testate amoebae in a soil under pine–oak forest
It is concluded that testate amoebae have a high potential as silica consumers and suppliers, and play a role comparable to that of higher plants in the terrestrial silica cycle. Expand
Environmental control on shell structure and composition of agglutinated foraminifera along a proximal-distal transect in the Marmara Sea
Abstract The study of benthic foraminifera in a complex marine system, like the Marmara Sea, is a key for understanding the influence of environmental factors on foraminiferal species, density,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
An Atlas of Freshwater Testate Amoebae
Using scanning electron micrographs, this book illustrates most of the common species of testate amoebae found in freshwater habitats and serves both as an identification guide and as an introduction to the biology and taxonomy of these freshwater protozoa. 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
Shell structure of some testate amoebae from Britain (Protozoa, Rhizopoda)
Summary Eleven species of testate amoebae are described, using scanning electron micrographs, all are common forms found in the British Isles. Detail of shell structure is given and in some casesExpand
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