• The diversity of testate amoebae will be estimated by both genetic techniques and more classical observations. (institut-polaire.fr)
  • 2018. Impact of two hot and dry summers on the community structure and functional diversity of testate amoebae in an artificial bog, illustrating their use as bioindicators of peatland health. (unine.ch)
  • 2018. Taxonomic and functional traits responses of Sphagnum peatland testate amoebae to experimentally manipulated water table. (unine.ch)
  • nov. from a Mexican desert: An unexpected new environment for hyalospheniid testate amoebae. (unine.ch)
  • The main testate amoebae groups are the lobose Tubulinea, which include Arcellinida, Difflugina and Phryganellina (within the Amoebozoa), and the filose Euglyphida (within the SAR supergroup), although there are smaller groups that also include other testate amoebae. (wikipedia.org)
  • The Arcellinida are the largest group of the testacea (shelled amoebae) containing about three quarters of the known species of these amoebae. (eol.org)
  • This dataset contains the digitized treatments in Plazi based on the original journal article Bobrov, Anatoly, Mazei, Yuri (2021): Meisterfeldia bitsevi-new testate amoeba of the family Cryptodifflugiidae Jung 1942 (Amoebozoa: Arcellinida) from the tree hollow in the urban park (Moscow Russia) with a key to species of the genus Meisterfeldia. (gbif.org)
  • Testate amoebae have proved an interesting group of indicator organisms in palaeoenvironmental studies and have also see more been used as bioindicators of human impact on ecosystems. (jaksignaling.com)
  • Testate amoebae (formerly thecamoebians, Testacea or Thecamoeba) are a polyphyletic group of unicellular amoeboid protists, which differ from naked amoebae in the presence of a test that partially encloses the cell, with an aperture from which the pseudopodia emerge, that provides the amoeba with shelter from predators and environmental conditions. (wikipedia.org)
  • Testate amoebae are unicellular organisms, largely enclosed by a shell. (eurekalert.org)
  • Testate amoebae (Protozoa: Rhizopoda) are unicellular shelled animals which live in abundance on the surface of most peat bogs. (microscopy-uk.org.uk)
  • Amoebas are unicellular protist microorganisms belonging to the genus amoeba of the family Amoebidae that contains five described genera. (hindawi.com)
  • Testate amoebae differ from naked amoebae with the presence of a test (shell) that helps provide shelter from predators and environmental conditions. (tpomag.com)
  • The test of some species is produced entirely by the amoeba and may be organic, siliceous or calcareous depending on the species (autogenic tests), whereas in other cases the test is made up of particles of sediment collected by the amoeba which are then agglutinated together by secretions from within the cell (xenogenic tests). (wikipedia.org)
  • Xenogenic testate amoeba covered in diatoms (from Penard's Amoeba Collection) Euglypha tuberculata, a species with a siliceous autogenic test The autogenic test of Arcella discoides, made up of organic plates Shell of Cyphoderia ampulla, composed of circular, siliceous plates produced by the amoeba Testate amoebae are a polyphyletic assemblage. (wikipedia.org)
  • Microworld - World of ameboid organisms - A database of both testate and naked amoebae with over 6,700 microphotographs and videos and over 1,700 species descriptions, as well as dichotomous and visual keys for identification. (wikipedia.org)
  • [1] Testate amoebae species have been used to reconstruct hydrological changes over the late Holocene , as a result of individual species possessing a narrow tolerance for ecohydrological conditions such as water-table depth or pH. (eol.org)
  • Thousands of testate amoebae species have been identified in nature and a wide range of species are observed in wastewater treatment systems. (tpomag.com)
  • From a practical standpoint identification of individual testate amoebae species is not common. (tpomag.com)
  • Thus, by characterizing the environmental constraints of testate amoeba communities within modern environment and by defining indicator species of all identifiable sub-environments, it is possible to reconstruct recent paleoenvironments and model the important changes operating in recent decades. (institut-polaire.fr)
  • 2) To propose a reconstruction of paleo-environments based on the statistical analysis of testate amoebae indicator species, extracted from sediment cores. (institut-polaire.fr)
  • The testate amoebae communities living among different species of mosses in Sphagnum peatlands in eastern Poland were studied. (limnology-journal.org)
  • however, few differences and morphological structures led to the lack of classification and differentiation between the diverse species of amoebas [ 9 ]. (hindawi.com)
  • He realized the one-celled life form was a new species of amoeba (Uh-MEE-buh). (snexplores.org)
  • Researchers discovered a new amoeba species in Brazil. (snexplores.org)
  • Lahr suspects many more amoeba species await discovery. (snexplores.org)
  • The disappearance of the previously abundant moss species Sphagnum imbricatum has been investigated at Butterburn Flow, northern England, using organic geochemical, elemental, macrofossil, pollen and testate amoebae analyses. (elsevierpure.com)
  • However, if you want to correctly reconstruct climate in such a layer, it's necessary to understand how testate amoeba communities respond to wildfire in current conditions. (eurekalert.org)
  • A seven metres thick peat bog (Misten, Hautes-Fagnes, Belgium) has been studied at high resolution in order to reconstruct the conditions of peat formation and evolution on the basis of pollen, testate amoebae analysis, and geochemistry. (ac.be)
  • Capabilities of the program are described together with some example plots of macrofossil, testate amoebae and pollen data. (mires-and-peat.net)
  • 2017. Response of sphagnum testate amoebae to drainage, subsequent re-wetting and associated changes in the moss carpet - results from a three year mesocosm experiment. (unine.ch)
  • Testate amoebae are sensitive indicators of hydrological conditions in peatlands, primarily the depth of the water table 2 . (microscopy-uk.org.uk)
  • Quantitative estimates of water tables and soil moisture in Holocene peatlands from testate amoebae. (microscopy-uk.org.uk)
  • Palaeohydrological records derived from testate amoebae analysis from peatlands in northern England: within-site variability, between-site comparability and palaeoclimate implications. (microscopy-uk.org.uk)
  • Reconstructing hydrological variability from testate amoebae analysis in Carpathian peatlands. (atomki.hu)
  • The results demonstrated that depth to water table, pH and total organic carbon can strongly regulate the abundance and taxonomic composition of testate amoebae. (limnology-journal.org)
  • Therefore, if the peat bog has a hydrological regime controlled by precipitation, the fossil testate amoebae preserved in a core sample of peat can be used to decipher past climatic conditions. (microscopy-uk.org.uk)
  • Holocene changes on a peatland in northwestern Ontario interpreted from testate amoebae (Protozoa) analysis. (microscopy-uk.org.uk)
  • However a recent review suggests that sexual recombination may be the rule rather than the exception in amoeboid protists in general, including the Arcellinid testate amoebae. (eol.org)
  • Although testate amoebae are among the better-studied protists, only little quantitative information exists on the morphology, phylogeny and ecology of cercozoan Rhogostomidae. (nih.gov)
  • The assemblage referred to as "testate amoebae" is actually composed of several, unrelated groups of organisms. (wikipedia.org)
  • With all current information, it is possible to speculate that the differences in amoebas could be associated with the presence or absence of flagella, developed with the expansion of these organisms to different substrates to seek favorable conditions promoting their survival, searching for nutrients from bacteria. (hindawi.com)
  • An International team from China University of Geosciences, University of York and Lomonosov Moscow State University have studied the impact of wildfire on testate amoebae -- one of the dominant microbial groups in peat bogs. (eurekalert.org)
  • Arcellinid testate amoebae are commonly found in soils, leaf litter , peat bogs and near/in fresh water. (eol.org)
  • Testate amoebae are theorized to be mostly polyphyletic (coming from more than one ancestral type), but testaceafilosea, one group of testate amoebae, are theorized to be monophyletic . (eol.org)
  • Testate amoebae significantly affect biochemical processes in peatland ecosystems. (eurekalert.org)
  • Euglyphid testate amoebae are closely related to the Foraminifera. (wikipedia.org)
  • Free-living amoebas (FLAs) develop their lives in the environment and are characterized by the lack of a cell wall in the trophozoite stage, which allows them to extend their cytoplasm to mobilize, resulting in the formation of pseudopods, further enabling them to feed on smaller microorganisms, mainly bacteria or decaying particles. (hindawi.com)
  • In this peek under the microscope, take an up-close look at testate amoebae. (tpomag.com)
  • The bog-surface wetness (BSW) proxy data (organic matter bulk density, C/N ratio, plant macrofossils and testate amoebae) highlight the importance of interactions between vegetation composition, microtopography and degree of peat decomposition, and show that the bog system operated consistently during the two wet shifts (dated to c. 2700 and 1000 cal a bp) despite different internal and external conditions. (lu.se)
  • Variations in water depth were reconstructed using a testate amoebae transfer function and inferred qualitatively using bulk elemental composition and biomarkers for changing redox conditions in the bog subsurface: the degree of isomerization in the C-31 hopanes, and the concentrations of bishomohopanol and archaeol. (elsevierpure.com)
  • Testate amoebae Cyclopyxis puteus Thomas (1960) has a characteristic morphology, that makes the possibility of overlook or misidentification unlikely. (nmnhs.com)
  • 1) To propose a denser and more exhaustive cartography of the amoeba communities in the different Kerguelen island landscape units following distincts gradients: a East-West precipitation gradient, a gradient of quality and quantity of the organic/inorganic substrate and a gradient of hydrolysis as revealed by clay minerals. (institut-polaire.fr)
  • Since these cores benefit from numerous analyzes from the point of view of organic, molecular and inorganic chemistry, we will benefit from an efficient database for the comparison of the paleoenvironments that we will reconstitute with the testate amoebae. (institut-polaire.fr)
  • Researchers from the Lomonosov Moscow State University, the University of Yorkand the University of Penza have previously proved that studies of testate amoebae's communities could be an effective tool for reconstructions of climatic changes in the past. (eurekalert.org)
  • Hello fellow testate amoeba researchers! (wikidot.com)
  • Testate amoebae can be found in most freshwater environments, including lakes, rivers, cenotes, as well as mires and soils. (wikipedia.org)
  • Naked amoeba (i. e. not testate) showing food vacuoles and ingested diatom Shell or test of a testate amoeba, Arcella sp. (wikipedia.org)
  • Some groups of testate amoebae (namely, that ones, which use silica plates for making their shells, laying these plates on the surface of the shell like roof tile) could "dissolve" solid silicon-containing components from the environment and produce out of them plates, used for constructing their shells. (eurekalert.org)
  • Some amoebas have a shell, as this one did. (snexplores.org)
  • Still other amoebas are "naked," lacking any shell. (snexplores.org)
  • The amoeba, they found, built its hat-shaped shell from proteins and sugars that it made. (snexplores.org)
  • Some amoebas carry bacteria that protect them from harm. (snexplores.org)
  • Testate amoebae analysis in ecological and paleoecological studies of wetlands: past, present and future" (PDF). (wikipedia.org)
  • At first testate amoebae are separated from a soil or moss substrate. (eurekalert.org)
  • The scientists assumed that amoebae, making their shells out of sandgrains, are more resistant to high temperatures, since their shells are thicker and more solid due to these grains of sand. (eurekalert.org)
  • Scientists still know little about amoebas. (snexplores.org)
  • Until recently, the testate amoebae of China were unknown to most western scientists, but our knowledge has improved greatly over the past 20 years. (jaksignaling.com)
  • Testate amoebae occur commonly in many types of wastewater treatment plants, including activated sludge, fixed film processes and lagoon systems. (tpomag.com)
  • This provided the opportunity to compare communities of testate amoebae from parts exposed and non-exposed to fire. (eurekalert.org)
  • Souto MS, Gonçalves V, Pontevedra-Pombal X, Raposeiro PM (2021) Distribution of testate amoebae in bryophyte communities in São Miguel Island (Azores Archipelago). (pensoft.net)
  • These conditions directly influence the structure of amoeba communities, mainly in aquatic-type environments [ 3 ]. (hindawi.com)
  • Ancient tests of terrestrial fauna are commonly found in fossilized amber, [7] although mid-Cretaceous testate amoeba (i.e. (eol.org)
  • After that the flask with this suspension is intensively shaken up and passed through a number of filters so that only amoebae shells and small suspended particles are left. (eurekalert.org)
  • Amoebas have largely "been ignored," notes Richard Payne. (snexplores.org)
  • Thus, the long-term project consists of setting up a tool for characterizing the environmental changes recorded in the subantarctic islands based on observation of preserved testate amoeba. (institut-polaire.fr)
  • Relationships between BSW records and environmental conditions within the study area were explored through both the development of a new central Ireland testate amoebae transfer function and through comparisons between recent BSW records and instrumental weather data. (reading.ac.uk)
  • On the other hand, the skeletons of these amoebae are preserved and are therefore witnesses of past environments. (institut-polaire.fr)
  • It was found out that fire led to significant changes in the structure of the testate amoeba community. (eurekalert.org)
  • The first description of an amoeba was in 1826 as a membranous type of microorganism whose shape is modified to move in the environment [ 7 ]. (hindawi.com)
  • This paper summarizes the testate amoebae research in China along with relevant data from other countries in Asia, and provides the necessary context for future research. (jaksignaling.com)
  • Fossils of arcellinid testate amoebae date back to the Tonian stage of the Proterozoic , around 789-759 million years ago. (eol.org)
  • To assess the importance of the vertical distribution of testate amoebae within the mosses, each sample was cut into two parts: the upper living part (1-5 cm) and the lower dead part (5-10 cm). (limnology-journal.org)