Testate amoebae
Encyclopedia
Testate amoebae are single-celled protists partially enclosed in a simple test
(shell).
They are commonly found in soils, leaf litter, peat bogs and near/in fresh water.
Almost all testate amoebae reproduce asexually
via binary fission. A sexual component to reproduction has not yet been found. Testate amoebae move by using pseudopodia (false feet), a temporary cell extension used for moving, and taking in food.
Testate amoebae taxa are differentiated by their test characteristics and what kind of pseudopodia they have (lobose, recticulose, or filose).
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incertae sedis
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Test (biology)
A test is a term used to refer to the shell of sea urchins, and also the shell of certain microorganisms, such as testate foraminifera and testate amoebae....
(shell).
They are commonly found in soils, leaf litter, peat bogs and near/in fresh water.
Almost all testate amoebae reproduce asexually
Asexual reproduction
Asexual reproduction is a mode of reproduction by which offspring arise from a single parent, and inherit the genes of that parent only, it is reproduction which does not involve meiosis, ploidy reduction, or fertilization. A more stringent definition is agamogenesis which is reproduction without...
via binary fission. A sexual component to reproduction has not yet been found. Testate amoebae move by using pseudopodia (false feet), a temporary cell extension used for moving, and taking in food.
Testate amoebae taxa are differentiated by their test characteristics and what kind of pseudopodia they have (lobose, recticulose, or filose).
Testate or shell
Simple testates (or shells) are be made by either secretion (autogenous tests) or by the agglutination of foreign material (xenogenous tests), or sometimes a combination of both. Past environmental changes can be determined by analysing the composition of fossil tests, including the reconstruction of past climate changeClimate change
Climate change is a significant and lasting change in the statistical distribution of weather patterns over periods ranging from decades to millions of years. It may be a change in average weather conditions or the distribution of events around that average...
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Evolutionary history
Fossils of testate amoebae date back to the Cryogenian period. 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 made up of one ancestral type (monophyletic). Ancient tests of terrestrial fauna are commonly found in fossilized amber , although an important new study has found mid-Cretaceous testate amoeba (i.e., Diffligia, Cucurbitella) in ancient lake sediments . It is likely that the group has evolved minimally over the course of the Phanerozoic.Classification
The group contains the following taxa :- Arcellina
- Arcellidae
- ArcellaArcellaArcella is a genus of testate amoebae or Arcellinida, usually found in freshwaters and mosses, and rarely in soils. A key characteristic of Arcella is the circular test with a hole on its center from where finger-like pseudopods emerge...
- Pyxidicula
- Antarcella
- Arcella
- Microchlamyiidae
- Microchlamys
- Microcoryciidae
- Microcorycia
- Diplochlamys
- ParmulinaParmulinaParmulina is a genus of fungi in the family Parmulariaceae.-Species:*Parmulina asterophora*Parmulina callista*Parmulina dimorphospora*Parmulina exsculpta*Parmulina japonica*Parmulina rehmii*Parmulina stenochlaenae...
- Zonomyxa
- Penardochlamys
- Arcellidae
- Difflugina
- Heleoperidae
- Awerintzewia
- HeleoperaHeleoperaHeleopera is a genus of Amoebozoa. It includes the species Heleopera sphagni....
- Difflugiidae
- DifflugiaDifflugiaDifflugia is one of several genera of amoebozoa that produce shells or tests from granules of sand. These are swallowed by the cell and during the process of budding or fission they pass into the daughter, where they are joined by organic cement. The test has a single terminal opening. Difflugia...
- Schwabia
- PentagoniaPentagoniaThe Pentagonia or the "five agonies' is the collective title of a series of five novels by Reinaldo Arenas, the Cuban writer. It was subtitled by its author "the secret history of Cuba." The novels were written from the mid 1960s through the late 1980s, and indeed, as was recounted in Arenas'...
- Maghrebia
- Zivkovicia
- Lagenodifflugia
- Pontigulasia
- Cucurbitella
- Suiadifflugia
- Sexangularia
- Difflugia
- Hyalospheniidae
- Hyalosphenia
- Leptochlamys
- Nebelidae
- Physochila
- Argynnia
- Nebela
- Alocodera
- Schoenbornia
- Certesella
- Porosia
- ApoderaApoderaApodera is a genus of Amoebozoa....
- Lesquereusiidae
- Lesquereusia
- Netzelia
- Pomoriella
- Quadrulella
- Microquadrula
- Paraquadrulidae
- Paraquadrula
- Lamtoquadrula
- Centropyxidae
- CentropyxisCentropyxisCentropyxis is a genus of Amoebozoa, including the species Centropyxis aculeata....
- Proplagiopyxis
- Centropyxiella
- Centropyxis
- Plagiopyxidae
- Bullinularia
- Geoplagiopyxis
- Protoplagiopyxis
- Paracentropyxis
- Plagiopyxis
- Hoogenradia
- Planhoogenradia
- Trigonopyxidae
- Trigonopyxis
- Cornuapyxis
- Cyclopyxis
- Geopyxella
- Ellipsopyxis
- Ellipsopyxella
- Distomatopyxidae
- Distomatopyxis
- Lamtopyxidae
- Lamtopyxis
- Heleoperidae
- Phryganellina
- Phryganellidae
- Phryganella
- Cryptodifflugiidae
- CryptodifflugiaCryptodifflugiaCryptodifflugia is a genus of rhizaria.It is sometimes grouped with Difflugiella....
- Wailesella
- Cryptodifflugia
- Phryganellidae
incertae sedis
Incertae sedis
, is a term used to define a taxonomic group where its broader relationships are unknown or undefined. Uncertainty at specific taxonomic levels is attributed by , , and similar terms.-Examples:*The fossil plant Paradinandra suecica could not be assigned to any...
:
- Geamphorella
- JungiaJungiaJungia is a genus of flowering plants in the aster family, Asteraceae.-Selected species:* Jungia crenatifolia* Jungia fistulosa* Jungia glandulifera* Jungia mitis* Jungia ovata...
- Oopyxis
- Pseudawerintzewia
- Pseudonebela