
''Syringammina'' is a
xenophyophore
Xenophyophorea is a clade of foraminiferans. Members of this class are multinucleate unicellular organisms found on the ocean floor throughout the world's oceans, at depths of . They are a kind of foraminiferan that extract minerals from their s ...
found off the coast of
Scotland
Scotland (, ) is a country that is part of the United Kingdom. Covering the northern third of the island of Great Britain, mainland Scotland has a border with England to the southeast and is otherwise surrounded by the Atlantic Ocean to th ...
, near
Rockall
Rockall () is an uninhabitable granite islet situated in the North Atlantic Ocean. The United Kingdom claims that Rockall lies within its exclusive economic zone (EEZ) and is part of its territory, but this claim is not recognised by Ireland. ...
. It is one of the largest
single-celled organism
A unicellular organism, also known as a single-celled organism, is an organism that consists of a single cell, unlike a multicellular organism that consists of multiple cells. Organisms fall into two general categories: prokaryotic organisms and ...
s known, at up to across.
It was
first described in 1882 by the
oceanographer
Oceanography (), also known as oceanology and ocean science, is the scientific study of the oceans. It is an Earth science, which covers a wide range of topics, including ecosystem dynamics; ocean currents, waves, and geophysical fluid dynamics ...
John Murray, after being discovered on an expedition in the ship ''Triton'' which dredged the deep ocean bed off the west coast of Scotland in an effort to find organisms new to science. It was the first xenophyophore to be described and at first its relationship with other organisms was a mystery, but it is now considered to be a member of the
Foraminifera
Foraminifera (; Latin for "hole bearers"; informally called "forams") are single-celled organisms, members of a phylum or class of amoeboid protists characterized by streaming granular ectoplasm for catching food and other uses; and commonly ...
.
The organism appears as an agglomeration of sediment a few centimetres across, a sandy ball that easily crumbles when removed from the seabed. It consists of a single cell which expands to form hundreds of hollow branched and interconnecting tubes; these secrete an organic cement to which particles of sediment and sand adhere, forming a crusty structure called the ''
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), ...
''. As the test grows, the cell withdraws from parts of it, which are then colonised by other organisms, such as
nematodes. The single cell has no cell divisions but is
multinucleate
Multinucleate cells (also known as multinucleated or polynuclear cells) are eukaryotic cells that have more than one nucleus per cell, i.e., multiple nuclei share one common cytoplasm. Mitosis in multinucleate cells can occur either in a coord ...
, having multiple
nuclei.
It is not known how the organism feeds or reproduces. It may be a
filter feeder
Filter feeders are a sub-group of suspension feeding animals that feed by straining suspended matter and food particles from water, typically by passing the water over a specialized filtering structure. Some animals that use this method of feedin ...
, drawing water through the tubes and sifting out the nutritious particles. Alternatively, much faecal matter accumulates in the tubes, and it has been suggested that it feeds on the bacteria that colonise the waste. This theory is supported by the fact that it has high concentrations of
lipid
Lipids are a broad group of naturally-occurring molecules which includes fats, waxes, sterols, fat-soluble vitamins (such as vitamins A, D, E and K), monoglycerides, diglycerides, phospholipids, and others. The functions of lipids incl ...
s within its
cytosol
The cytosol, also known as cytoplasmic matrix or groundplasm, is one of the liquids found inside cells ( intracellular fluid (ICF)). It is separated into compartments by membranes. For example, the mitochondrial matrix separates the mitochondri ...
, which suggests that it may feed on bacteria from the sediment that makes up the tubes. In common with other xenophyophores, the organism has tiny crystals of
barium sulphate
Barium sulfate (or sulphate) is the inorganic compound with the chemical formula Ba SO4. It is a white crystalline solid that is odorless and insoluble in water. It occurs as the mineral barite, which is the main commercial source of barium an ...
, known as granellae, scattered throughout the cytosol.
''Syringammina fragilissima'', the first xenophyophore known to science, was described by Henry Bowman Brady in 1883, from specimens dredged from the Faroe Channel.
''S. minuta'', described by Pearcey in 1914, was not properly figured and the original specimen is unaccounted for.
The species ''Syringammina limosa'' was described in 2018 from the
Sea of Okhotsk
The Sea of Okhotsk ( rus, Охо́тское мо́ре, Ohótskoye móre ; ja, オホーツク海, Ohōtsuku-kai) is a marginal sea of the western Pacific Ocean. It is located between Russia's Kamchatka Peninsula on the east, the Kuril Islands ...
at a depth of 3300 metres.
References
External links
Article containing a photograph of a specimenfrom ''
New Scientist
''New Scientist'' is a magazine covering all aspects of science and technology. Based in London, it publishes weekly English-language editions in the United Kingdom, the United States and Australia. An editorially separate organisation publish ...
''
*
{{Taxonbar, from1=Q20672776, from2=Q3020957
Biota of Scotland
Foraminifera genera
Xenophyophorea