''Porosia'' is a genus of 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 ...

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 ...

. Described in 1942, it used to be a monotypic genus with the sole species '' P. bigibbosa''. However a second species, '' P. paracarinata'', was discovered in 2015.

Morphology

The original 1942 description of ''Porosia'' corresponds to the type species '' P. bigibbosa''. The description was expanded in 2015 to fit both species. The organism consists of a pyriform, laterally compressed

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), ...

with a rounded posterior end, two large invaginated pores situated on each lateral compression, both of which connected by internal tubes in ''

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 ...

''. Small lateral pores are seen anterior to the large ones. Lateral keels, present in '' P. paracarinata'' but absent in '' P. bigibbosa'', surround a third of the posterior lateral margins. The test itself is composed of

euglyphid The euglyphids are a prominent group of filose amoebae that produce shells or tests from siliceous scales, plates, and sometimes spines. These elements are created within the cell and then assembled on its surface in a more or less regular arra ...

shell plates embedded in a disorganized cement. The test's aperture or "pseudostome" is surrounded with a lip made of organic compounds. It is closely related to ''

'', but lacks a punctuated neck.

Ecology

''Porosia'' species are rare and have been seen inhabiting ''

Sphagnum ''Sphagnum'' is a genus of approximately 380 accepted species of mosses, commonly known as sphagnum moss, peat moss, also bog moss and quacker moss (although that term is also sometimes used for peat). Accumulations of ''Sphagnum'' can store wa ...

moss Mosses are small, non-vascular flowerless plants in the taxonomic division Bryophyta (, ) '' sensu stricto''. Bryophyta (''sensu lato'', Schimp. 1879) may also refer to the parent group bryophytes, which comprise liverworts, mosses, and hor ...

es, forest litter and

soil Soil, also commonly referred to as earth or dirt, is a mixture of organic matter, minerals, gases, liquids, and organisms that together support life. Some scientific definitions distinguish ''dirt'' from ''soil'' by restricting the former te ...

References

External links

{{taxonbar, from=Q26447096 Amoebozoa genera Tubulinea