''Nebela'' is a diverse genus of

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 ...

cosmopolitan distribution In biogeography, cosmopolitan distribution is the term for the range of a taxon that extends across all or most of the world in appropriate habitats. Such a taxon, usually a species, is said to exhibit cosmopolitanism or cosmopolitism. The ext ...

, belonging to the 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 ...

. They are "prey agglutinated" or "kleptosquamic" organisms, meaning they take the inorganic plates from their prey to construct their

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), ...

Morphology

Members of this genus have a thin, transparent, pseudochitinous, flattened

that can be ovate, pyriform or elongate, with a length of around 180

micron The micrometre ( international spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American spelling), also commonly known as a micron, is a unit of length in the International System of Unit ...

s. The surface of the test has numerous oval or circular scales of variable size, or in rare occasions rectangular or rod-like scales. The

protoplasm Protoplasm (; ) is the living part of a cell that is surrounded by a plasma membrane. It is a mixture of small molecules such as ions, monosaccharides, amino acid, and macromolecules such as proteins, polysaccharides, lipids, etc. In some defini ...

is granular and colorless but can contain food

vacuole A vacuole () is a membrane-bound organelle which is present in plant and fungal cells and some protist, animal, and bacterial cells. Vacuoles are essentially enclosed compartments which are filled with water containing inorganic and organic mo ...

s that show color. They have a single

nucleus Nucleus ( : nuclei) is a Latin word for the seed inside a fruit. It most often refers to: *Atomic nucleus, the very dense central region of an atom *Cell nucleus, a central organelle of a eukaryotic cell, containing most of the cell's DNA Nucle ...

and a variable number of

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 ...

that are blunt in shape. The cell body is attached to the test's interior by strands of ectoplasm.

Classification

''Nebela'' originally belonged to the family Nebelidae, but phylogenetic analyses showed that the genus was

paraphyletic In taxonomy (general), taxonomy, a group is paraphyletic if it consists of the group's most recent common ancestor, last common ancestor and most of its descendants, excluding a few Monophyly, monophyletic subgroups. The group is said to be pa ...

and the genera ''

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 ...

'' and ''

Quadrulella 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 ...

'', which belong to

, branch within ''Nebela''. Accordingly, the family Nebelidae was synonymised with

. There are at least 13 remaining species in the genus: *''Nebela'' **'' Nebela acolla'' **'' Nebela aliciae'' **'' Nebela barbata'' **'' Nebela carinatella'' **'' Nebela collaris'' (=''

Difflugia ''Difflugia'' is the largest genus of Arcellinida, one of several groups of Tubulinea within the eukaryote supergroup Amoebozoa. Arcellinida species produce shells or tests from mineral particles or biogeonic elements (e.g. diatom frustules) and a ...

collaris'' ; =''D. cancellata'' ; =''D. reticulata'' ; =''D. carpio'' ; =''D. laxa'' ; =''D. cellulifera'' ; =''N. numata'' ; =''N. bohemica'' ; =''N. sphagnophila'' ; =''N. tincta'' var. ''major'' ; =''N. tincta'' f. ''stenostoma'' ) **'' Nebela equicalceus'' (=''N. hippocrepis'') **'' Nebela flabellulum'' **'' Nebela guttata'' **'' Nebela meisterfeldi'' **'' Nebela pechorensis'' **'' Nebela rotunda'' **'' Nebela tenella'' **'' Nebela tincta'' (=''

tincta'' ; =''N. bursella'' ; =''N. parvula'' ; =''N. minor'' )

Former species

The

paraphyly In taxonomy, a group is paraphyletic if it consists of the group's last common ancestor and most of its descendants, excluding a few monophyletic subgroups. The group is said to be paraphyletic ''with respect to'' the excluded subgroups. In co ...

of ''Nebela'' is slowly being resolved by transfering species from ''Nebela'' to other genera through phylogenetic analyses. The following species were previously considered ''Nebela'' but have been moved accordingly: *''

Alabasta ''Alabasta'' () is a genus of arcellinid testate amoebae belonging to the family Hyalospheniidae. It contains species with an elongated test and a strongly curved "pseudostome" (the test opening) with a flare and a notch in narrow view. These s ...

'' **''

Alabasta kivuense ''Alabasta'' () is a genus of arcellinid testate amoebae belonging to the family Hyalospheniidae. It contains species with an elongated test and a strongly curved "pseudostome" (the test opening) with a flare and a notch in narrow view. These s ...

'' (=''Nebela kivuense'' ) **''

Alabasta longicollis ''Alabasta'' () is a genus of arcellinid testate amoebae belonging to the family Hyalospheniidae. It contains species with an elongated test and a strongly curved "pseudostome" (the test opening) with a flare and a notch in narrow view. These s ...

'' (=''Nebela longicollis'' ) **''

Alabasta militaris ''Alabasta'' () is a genus of arcellinid testate amoebae belonging to the family Hyalospheniidae. It contains species with an elongated test and a strongly curved "pseudostome" (the test opening) with a flare and a notch in narrow view. These s ...

'' (=''Nebela militaris'' ; =''N. bursella'' ; =''Nebela americana'' var. ''bryophila'' ) *'' Cornutheca'' **'' Cornutheca ansata'' (=''Nebela ansata'' ) **'' Cornutheca saccifera'' (=''Nebela saccifera'' ) **'' Cornutheca jiuhuensis'' (=''Nebela jiuhuensis'' ) *'' Gibbocarina'' **'' Gibbocarina galeata'' (=''Nebela galeata'' ) *'' Longinebela'' **'' Longinebela golemanskyi'' (=''Nebela golemanskyi'' ) **'' Longinebela penardiana'' (=''Nebela penardiana'' ) **'' Longinebela speciosa'' (=''Nebela speciosa'' ) **'' Longinebela tubulosa'' (=''Nebela tubulosa'' ) *''

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 ...

'' **'' Netzelia tuberculata'' (=''Nebela tuberculata'' ) *'' Padaungiella'' **'' Padaungiella lageniformis'' (=''Nebela lageniformis'' ) **'' Padaungiella wailesi'' (=''Nebela wailesi'' ) **'' Padaungiella wetekampi'' (=''Nebela wetekampi'' ) **'' Padaungiella tubulata'' (=''Nebela tubulata'' ) **'' Padaungiella nebeloides'' (=''Nebela nebeloides '' ) *''

Planocarina ''Planocarina'' () is a genus of arcellinid testate amoebae belonging to the family Hyalospheniidae. It was created in 2016 to agglutinate a clade of species that were previously assigned to the paraphyletic genus ''Nebela''. All species of '' ...

'' **'' Planocarina carinata'' (=''Nebela carinata'' ) **'' Planocarina marginata'' (=''Nebela marginata'' ) **'' Planocarina maxima'' (=''Nebela maxima'' ) **'' Planocarina spumosa'' (=''Nebela spumosa'' ) *'' Physochila'' **'' Physochila griseola'' (=''Nebela griseola'' )

References

External links

{{taxonbar, from=Q11790411 Amoebozoa genera Tubulinea