Arcellinid

testate amoebae 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 ...

or Arcellinida,http://www.microscopy-uk.org.uk/mag/artjun03/gsamoebae.html Testate amoebae, peat bogs and past climates. accessed 16 march 2007 Arcellacean or lobose testate amoebae are single-celled

protists A protist () is any eukaryotic organism (that is, an organism whose cells contain a cell nucleus) that is not an animal, plant, or fungus. While it is likely that protists share a common ancestor (the last eukaryotic common ancestor), the excl ...

partially enclosed in a simple

test Test(s), testing, or TEST may refer to: * Test (assessment), an educational assessment intended to measure the respondents' knowledge or other abilities Arts and entertainment * ''Test'' (2013 film), an American film * ''Test'' (2014 film), ...

(shell). Arcellinid testate amoebae are commonly found in soils, leaf litter, peat bogs and near/in fresh water. They use their

pseudopodia A pseudopod or pseudopodium (plural: pseudopods or pseudopodia) is a temporary arm-like projection of a eukaryotic cell membrane that is emerged in the direction of movement. Filled with cytoplasm, pseudopodia primarily consist of actin filament ...

, a temporary cell extension, for moving and taking in food. Like most amoebae, they are generally believed to

reproduce asexually Asexual reproduction is a type of reproduction that does not involve the fusion of gametes or change in the number of chromosomes. The offspring that arise by asexual reproduction from either unicellular or multicellular organisms inherit the fu ...

via binary fission. However a recent review suggests that sexual recombination may be the rule rather than the exception in

amoeboid An amoeba (; less commonly spelled ameba or amœba; plural ''am(o)ebas'' or ''am(o)ebae'' ), often called an amoeboid, is a type of cell or unicellular organism with the ability to alter its shape, primarily by extending and retracting pseudopo ...

protists in general, including the Arcellinid testate amoebae.

Test or shell

Simple tests are made by secretion (autogenous tests), 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 change In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to E ...

. Testate amoebae species have been used to reconstruct hydrological changes over the late

Holocene The Holocene ( ) is the current geological epoch. It began approximately 11,650 cal years Before Present (), after the Last Glacial Period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene togethe ...

, as a result of individual species possessing a narrow tolerance for ecohydrological conditions such as water-table depth or pH.

Evolutionary history

Fossils of arcellinid testate amoebae date back to the

Tonian The Tonian (from grc, τόνος, tónos, meaning "stretch") is the first geologic period of the Neoproterozoic era (geology), Era. It lasted from to Mya (million years ago). Instead of being based on stratigraphy, these dates are defined by t ...

stage of the

Proterozoic The Proterozoic () is a geological eon spanning the time interval from 2500 to 538.8million years ago. It is the most recent part of the Precambrian "supereon". It is also the longest eon of the Earth's geologic time scale, and it is subdivided ...

, around 789-759 million years ago. The fossils indicate that by 730 million years ago, arcellinids had already diversified into major lineages. Testate amoebae are theorized to be mostly

polyphyletic A polyphyletic group is an assemblage of organisms or other evolving elements that is of mixed evolutionary origin. The term is often applied to groups that share similar features known as homoplasies, which are explained as a result of converg ...

(coming from more than one ancestral type), but testaceafilosea, one group of testate amoebae, are theorized to be

monophyletic In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic gro ...

. Ancient tests of terrestrial fauna are commonly found in fossilized amber, although mid-Cretaceous testate amoeba (i.e., ''Diffligia'', ''Cucurbitella'') have been found in ancient lake sediments. It is likely that the group has evolved minimally over the course of the

Phanerozoic The Phanerozoic Eon is the current geologic eon in the geologic time scale, and the one during which abundant animal and plant life has existed. It covers 538.8 million years to the present, and it began with the Cambrian Period, when anima ...

Classification

The classification of Arcellinida, as of 2019: * Suborder

Phryganellina Arcellinid testate amoebae or Arcellinida,http://www.microscopy-uk.org.uk/mag/artjun03/gsamoebae.html Testate amoebae, peat bogs and past climates. accessed 16 march 2007 Arcellacean or lobose testate amoebae are single-celled protists partially ...

Bovee 1985 ** Family

Phryganellidae Arcellinid testate amoebae or Arcellinida,http://www.microscopy-uk.org.uk/mag/artjun03/gsamoebae.html Testate amoebae, peat bogs and past climates. accessed 16 march 2007 Arcellacean or lobose testate amoebae are single-celled protists partially ...

Jung 1942 *** ''

Phryganella Arcellinid testate amoebae or Arcellinida,http://www.microscopy-uk.org.uk/mag/artjun03/gsamoebae.html Testate amoebae, peat bogs and past climates. accessed 16 march 2007 Arcellacean or lobose testate amoebae are single-celled protists partially ...

'' Penard 1902 ** Family

Cryptodifflugiidae Cryptodifflugiidae is a family of arcellinid testate amoebae. Description Members of this family are conopodous (with conical pseudopods) amoebae with the body in a clear, usually firm, vase-shaped test, and conical pseudopods for locomotion t ...

Jung 1942 *** ?''

Prantlitina ''Prantlitina'' is a poorly studied genus of testate amoebae discovered in 1957 in Namurian freshwater sediments from the Ostrava-Karviná coal district, in former Czechoslovakia. It was placed in the order Thecamoebina in the defunct class Sarc ...

'' Vasicek & Ruzicka 1957 *** ?''

Pseudocucurbitella ''Pseudocucurbitella'' is a genus of freshwater testate amoebae of the order Arcellinida. Its shell is agglutinated, ovoid, with a round crossection and a circular aperture surrounded by 3 to 5 separate lobes forming a short collar. Originally ...

'' Gauthier-Lievre & Thomas 1960 *** ?'' Pseudowailesella'' Sudzuki 1979 *** ''

Cryptodifflugia ''Cryptodifflugia'' is a genus of arcellinid testate amoebae. It contains all the species previously grouped as the genus ''Difflugiella'', which is now a synonym of ''Cryptodifflugia''. Description ''Cryptodifflugia'' species are characteriz ...

'' Penard 1890 'Difflugiella'' Cash 1904; ''Geococcus (eukaryote)">Geococcus'' Francé 1913 non Green 1902">Difflugiella">'Difflugiella'' Cash 1904; ''Geococcus (eukaryote)">Geococcus'' Francé 1913 non Green 1902*** ''Meisterfeldia'' Bobrov 2016 *** ''Wailesella'' Deflandre 1928 * Suborder Organoconcha Lahr et al. 2019 ** Family Microchlamyiidae Ogden 1985 *** '' Microchlamys'' Cockerell 1911 'Pseudochlamys'' Claparede & Lachmann 1859 non Lacordaire 1848 non Comas 1977">Pseudochlamys.html" ;"title="'Pseudochlamys">'Pseudochlamys'' Claparede & Lachmann 1859 non Lacordaire 1848 non Comas 1977*** ''Pyxidicula'' Ehrenberg 1838 non Ehrenberg 1834 non Strelnikova & Nikolajev 1986 *** ''Spumochlamys'' Kudryavtsev & Hausmann 2007 * Suborder Glutinoconcha Lahr et al. 2019 ** Infraorder Volnustoma Lahr et al. 2019 *** Family

Heleoperidae Arcellinid testate amoebae or Arcellinida,http://www.microscopy-uk.org.uk/mag/artjun03/gsamoebae.html Testate amoebae, peat bogs and past climates. accessed 16 march 2007 Arcellacean or lobose testate amoebae are single-celled protists partially ...

Jung 1942 **** '' Awerintzewia'' Schouteden 1906 **** ''

Heleopera ''Heleopera'' is a genus of Amoebozoa Amoebozoa is a major taxonomic group containing about 2,400 described species of amoeboid protists, often possessing blunt, fingerlike, lobose pseudopods and tubular mitochondrial cristae. In traditional ...

'' Leidy 1879 ** Infraorder

Hyalospheniformes Hyalospheniidae is a group of testate amoebae and the sole family of the infraorder Hyalospheniformes. Hyalospheniid testate amoebae are considered important bioindicators, which is why they are frequently used for environmental monitoring and the ...

Lahr et al. 2019 *** Family

Hyalospheniidae Hyalospheniidae is a group of testate amoebae and the sole family of the infraorder Hyalospheniformes. Hyalospheniid testate amoebae are considered important bioindicators, which is why they are frequently used for environmental monitoring and the ...

Schulze, 1977 ebelidae Taranek 1882**** ?'' Apolimia'' Korganova 1987 **** ?'' Deflandria'' Jung 1942 **** ?'' Heleoporella'' Couteaux 1978 **** ?'' Leidyella'' Jung 1942 **** ?'' Metaheleopera'' Bartos 1954 **** ?'' Marsipos'' Medioli et al. 1990 **** ?'' Paranebela'' Jung 1942 **** ?''

Penardiella ''Legendrea'' is a genus of extremely rare ciliates first described by French biologist Fauré-Fremiet in 1908, rediscovered and re-examined in 2022. Classification The genus has 5 species including the type species In zoological nomenclatur ...

'' Kahl 1930 **** ?'' Pseudogeamphorella'' Décloitre 1964 nomen nudum **** ?'' Pseudohyalosphenia'' Stepanek 1967 nomen nudum **** ?'' Pterygia'' Jung 1942 non Roeding 1798 non Link 1807 non Laporte 1832 **** ?'' Schaudinnia'' Jung 1942 non Schulze 1900 **** ?'' Umbonaria'' Jung 1942 **** '' Alabasta'' Duckert et al. 2018 **** ''

Alocodera Arcellinid testate amoebae or Arcellinida,http://www.microscopy-uk.org.uk/mag/artjun03/gsamoebae.html Testate amoebae, peat bogs and past climates. accessed 16 march 2007 Arcellacean or lobose testate amoebae are single-celled protists partially ...

'' Jung 1942a **** '' Apodera'' Loeblich & Tappan 1961 **** ''

Certesella Arcellinid testate amoebae or Arcellinida,http://www.microscopy-uk.org.uk/mag/artjun03/gsamoebae.html Testate amoebae, peat bogs and past climates. accessed 16 march 2007 Arcellacean or lobose testate amoebae are single-celled protists partially ...

'' Loeblich & Tappan 1961 **** '' Cornutheca'' Kosakyan et al. 2016 **** '' Gibbocarina'' Kosakyan et al. 2016 **** ''

Hyalosphenia Arcellinid testate amoebae or Arcellinida,http://www.microscopy-uk.org.uk/mag/artjun03/gsamoebae.html Testate amoebae, peat bogs and past climates. accessed 16 march 2007 Arcellacean or lobose testate amoebae are single-celled protists partiall ...

'' Stein 1859 **** '' Longinebela'' Kosakyan et al. 2016 **** '' Mrabella'' Kosakyan et al. 2016 **** '' Nebela'' Leidy 1875 **** '' Padaungiella'' Lara & Todorov 2012 **** '' Planocarina'' Kosakyan et al. 2016 **** ''

Porosia ''Porosia'' is a genus of arcellinid testate amoebae belonging to the family Hyalospheniidae. Described in 1942, it used to be a monotypic genus with the sole species '' P. bigibbosa''. However a second species, '' P. paracarinata'', was discove ...

'' Jung 1942 **** '' Quadrulella'' Cockerell 1909 'Quadrula'' Schulze 1875 non Rafinesque 1820">Quadrula.html" ;"title="'Quadrula">'Quadrula'' Schulze 1875 non Rafinesque 1820** Infraorder Excentrostoma Lahr et al. 2019 *** ?''Centropyxiella'' Valkanov 1970 *** ?''Oopyxis'' Jung 1942 *** Family Centropyxidae **** ''Armipyxis'' Dekhtiar 2009 **** '' Centropyxis'' Stein 1857 'Echinopyxis'' Claparede & Lachmann 1859 non Pantocsek 1913; ''Collaripyxidia">Echinopyxis.html" ;"title="'Echinopyxis">'Echinopyxis'' Claparede & Lachmann 1859 non Pantocsek 1913; ''Collaripyxidia'' Zivkovic 1975; ''Toquepyxis'' Laminger 1971] **** ''Conicocassis'' Nasser & Patterson 2015 **** ''Proplagiopyxis'' Schönborn 1964 *** Family Plagiopyxidae **** ''

Bullinularia Arcellinid testate amoebae or Arcellinida,http://www.microscopy-uk.org.uk/mag/artjun03/gsamoebae.html Testate amoebae, peat bogs and past climates. accessed 16 march 2007 Arcellacean or lobose testate amoebae are single-celled protists partially ...

'' Deflandre 1953 'Bullinula'' Penard 1911">Bullinula.html" ;"title="'Bullinula">'Bullinula'' Penard 1911**** ''Geoplagiopyxis'' Chardez 1961 **** ''Hoogenraadia'' GauthierLievre & Thomas 1958 **** ''Paracentropyxis'' Bonnet 1960 **** ''Plagiopyxis'' Penard 1910 **** '' Planhoogenraadia'' Bonnet 1977 **** ''

Protoplagiopyxis Arcellinid testate amoebae or Arcellinida,http://www.microscopy-uk.org.uk/mag/artjun03/gsamoebae.html Testate amoebae, peat bogs and past climates. accessed 16 march 2007 Arcellacean or lobose testate amoebae are single-celled protists partially ...

'' Bonnet 1962 ** Infraorder Longithecina Lahr et al. 2019 *** Family

Lesquereusiidae Arcellinid testate amoebae or Arcellinida,http://www.microscopy-uk.org.uk/mag/artjun03/gsamoebae.html Testate amoebae, peat bogs and past climates. accessed 16 march 2007 Arcellacean or lobose testate amoebae are single-celled protists partially ...

araquadrulidae Deflandre 1953**** '' Fabalesquereusia'' Snegovaya & Alekperov 2005 **** ''

Lesquereusia Arcellinid testate amoebae or Arcellinida,http://www.microscopy-uk.org.uk/mag/artjun03/gsamoebae.html Testate amoebae, peat bogs and past climates. accessed 16 march 2007 Arcellacean or lobose testate amoebae are single-celled protists partially ...

'' Schlumberger 1845 **** '' Microquadrula'' Golemansky 1968 **** ''

Paraquadrula Arcellinid testate amoebae or Arcellinida,http://www.microscopy-uk.org.uk/mag/artjun03/gsamoebae.html Testate amoebae, peat bogs and past climates. accessed 16 march 2007 Arcellacean or lobose testate amoebae are single-celled protists partially ...

'' Deflandre 1932 **** ''

Pomoriella Arcellinid testate amoebae or Arcellinida,http://www.microscopy-uk.org.uk/mag/artjun03/gsamoebae.html Testate amoebae, peat bogs and past climates. accessed 16 march 2007 Arcellacean or lobose testate amoebae are single-celled protists partially ...

'' Golemansky 1970 *** Family Difflugiidae Wallich 1864 **** ?''

Lagenodifflugia Arcellinid testate amoebae or Arcellinida,http://www.microscopy-uk.org.uk/mag/artjun03/gsamoebae.html Testate amoebae, peat bogs and past climates. accessed 16 march 2007 Arcellacean or lobose testate amoebae are single-celled protists partially ...

'' Medioli & Scott 1983 **** ?''

Maghrebia Arcellinid testate amoebae or Arcellinida,http://www.microscopy-uk.org.uk/mag/artjun03/gsamoebae.html Testate amoebae, peat bogs and past climates. accessed 16 march 2007 Arcellacean or lobose testate amoebae are single-celled protists partially ...

'' Gauthier-Lievre & Thomas 1958 **** ?'' Pentagonina'' Bovee & Jahn 1974

Pentagonia The ''Pentagonia'' is the collective title of a series of five novels by Cuban author Reinaldo Arenas. 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, ...

'' Gauthier-Lievre & Thomas 1958 non Cozzens 1846; ''Falsidifflugia'' Haman 1988] **** ?''Pseudopontigulasia'' Oye 1956 **** ?''Sexangularia'' Awerintzew 1906 **** ?''Suiadifflugia'' Green 1975 **** ?'' Zivkovicia'' Ogden 1987 **** '' Armatodifflugia'' Snegovaya & Alekperov 2005 **** '' Difflugia'' Leclere 1815 ex Lamarck 1816 **** '' Mediolus'' Patterson 2014 **** '' Nabranella'' Snegovaya & Alekperov 2009 **** '' Pelecyamoeba'' Snegovaya & Alekperov 2005 **** '' Pontigulasia'' Rhumbler 1895 **** '' Pseudonebela'' Gauthier-Lievre 1954 non Schönborn 1964 ** Infraorder Sphaerothecina Kosakyan et al. 2016 *** ?''

Cornuapyxis Arcellinid testate amoebae or Arcellinida,http://www.microscopy-uk.org.uk/mag/artjun03/gsamoebae.html Testate amoebae, peat bogs and past climates. accessed 16 march 2007 Arcellacean or lobose testate amoebae are single-celled protists partially ...

'' Couteaux & Chardez 1981 *** ?''

Cucurbitella Arcellinid testate amoebae or Arcellinida,http://www.microscopy-uk.org.uk/mag/artjun03/gsamoebae.html Testate amoebae, peat bogs and past climates. accessed 16 march 2007 Arcellacean or lobose testate amoebae are single-celled protists partially ...

'' Penard 1902 non Walpers 1846 *** ?''

Ellipsopyxella Arcellinid testate amoebae or Arcellinida,http://www.microscopy-uk.org.uk/mag/artjun03/gsamoebae.html Testate amoebae, peat bogs and past climates. accessed 16 march 2007 Arcellacean or lobose testate amoebae are single-celled protists partially ...

'' Bonnet 1975 *** ?'' Ellipsopyxis'' Bonnet 1965 *** ?'' Protocucurbitella'' Gauthier-Lievre & Thomas 1960 non Naumov *** Family

Distomatopyxidae Arcellinid testate amoebae or Arcellinida,http://www.microscopy-uk.org.uk/mag/artjun03/gsamoebae.html Testate amoebae, peat bogs and past climates. accessed 16 march 2007 Arcellacean or lobose testate amoebae are single-celled protists partially ...

Bonnet 1970 **** ''

Distomatopyxis Arcellinid testate amoebae or Arcellinida,http://www.microscopy-uk.org.uk/mag/artjun03/gsamoebae.html Testate amoebae, peat bogs and past climates. accessed 16 march 2007 Arcellacean or lobose testate amoebae are single-celled protists partially ...

'' Bonnet 1970 *** Family

Lamtopyxidae Arcellinid testate amoebae or Arcellinida,http://www.microscopy-uk.org.uk/mag/artjun03/gsamoebae.html Testate amoebae, peat bogs and past climates. accessed 16 march 2007 Arcellacean or lobose testate amoebae are single-celled protists partially ...

Bonnet 1974 **** ''

Lamtopyxis Arcellinid testate amoebae or Arcellinida,http://www.microscopy-uk.org.uk/mag/artjun03/gsamoebae.html Testate amoebae, peat bogs and past climates. accessed 16 march 2007 Arcellacean or lobose testate amoebae are single-celled protists partially ...

'' Bonnet 1974 *** Family Netzeliidae Kosakyan et al. 2016 yclopyxidae Schönborn 1989**** '' Cyclopyxis'' Bonnet 1953 **** ''

Netzelia Arcellinid testate amoebae or Arcellinida,http://www.microscopy-uk.org.uk/mag/artjun03/gsamoebae.html Testate amoebae, peat bogs and past climates. accessed 16 march 2007 Arcellacean or lobose testate amoebae are single-celled protists partially ...

'' Ogden 1979 *** Family

Arcellidae ''Arcella'' is a genus of testate amoebae in the order 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 pseudopod ...

Ehrenberg 1832 **** ''

Antarcella ''Arcella'' is a genus of testate amoebae in the order Arcellinida, usually found in freshwaters and mosses, and rarely in soils. A key characteristic of ''Arcella'' is the circular Test (biology), test with a hole on its center from where finge ...

'' Ehrenberg 1838 **** ''

Arcella ''Arcella'' is a genus of testate amoebae in the order 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 pseudopod ...

'' Deflandre 1928 'Arcellina'' Carter 1856 non DuPlessis 1876 non Haeckel 1894; ''Cyphidium">Arcellina.html" ;"title="'Arcellina">'Arcellina'' Carter 1856 non DuPlessis 1876 non Haeckel 1894; ''Cyphidium'' Ehrenberg 1837 non Magnus 1875; ''Leptocystis'' Playfair 1918] *** Trigonopyxidae Loeblich 1964 **** ''Geopyxella'' Bonnet & Thomas 1955 **** ''Trigonopyxis'' Penard 1912 Arcellinida incertae sedis: * '' Argynnia'' Vucetich, 1974 * '' Awerintzewia'' Schouteden, 1906 * '' Geamphorella'' Bonnet, 1959 * ''

Jungia ''Jungia'' is a genus of flowering plants in the family Asteraceae. It is native mostly to South America, with one widespread species extending its range into Central America and southern Mexico. Species accepted by the Plants of the World Onlin ...

'' Loeblich & Tappan 1961 * ''

'' Medioli & Scott, 1983 * ''

Lamtoquadrula Arcellinid testate amoebae or Arcellinida,http://www.microscopy-uk.org.uk/mag/artjun03/gsamoebae.html Testate amoebae, peat bogs and past climates. accessed 16 march 2007 Arcellacean or lobose testate amoebae are single-celled protists partially ...

'' Bonnet 1975 * '' Leptochlamys'' West 1901 * ''

'' Gauthier-Lievre & Thomas, 1960 * '' Ochros'' Medioli et al. 1990 * †'' Palaeoleptochlamys'' Strullu-Derrien et al. 2019 * ''

Physochila Arcellinid testate amoebae or Arcellinida,http://www.microscopy-uk.org.uk/mag/artjun03/gsamoebae.html Testate amoebae, peat bogs and past climates. accessed 16 march 2007 Arcellacean or lobose testate amoebae are single-celled protists partially ...

'' Jung 1942 * '' Pseudawerintzewia'' Bonnet 1959 * '' Sacculus'' Medioli et al. 1990 non Gosse 1851 non Hirase 1927 non Neviani 1930 * '' Schoenbornia'' Decloitre 1964 * ''

Swabia Swabia ; german: Schwaben , colloquially ''Schwabenland'' or ''Ländle''; archaic English also Suabia or Svebia is a cultural, historic and linguistic region in southwestern Germany. The name is ultimately derived from the medieval Duchy of ...

'' * Family Bipseudostomatidae Snegovaya & Alekperov 2005 ** '' Bipseudostomatella'' Snegovaya & Alekperov 2005 ** '' Gomocollariella'' Snegovaya & Alekperov 2005 * Family Mississippiellidae Huddleston & Haman 1985 ** '' Mississippiella'' Haman 1982 * Family Shamkiriidae Snegovaya & Alekperov 2005 ** '' Shamkiriella'' Snegovaya & Alekperov 2005

References

External links

ISTAR, the International Society for Testate Amoeba Research

Tree of Life: Arcellinida

* ttp://www.micrographia.com/specbiol/protis/homamoeb/amts0100.htm Protozoa: The testate amoebae
BioImages: The Virtual Field-Guide (UK) - TESTACEA (Testate amoebae)

Pictures of testate amoebae
{{Taxonbar, from=Q136129 Amoebozoa orders Tubulinea