
''Syringammina'' is a
xenophyophore found off the coast of
Ireland
Ireland (, ; ; Ulster Scots dialect, Ulster-Scots: ) is an island in the North Atlantic Ocean, in Northwestern Europe. Geopolitically, the island is divided between the Republic of Ireland (officially Names of the Irish state, named Irelan ...
, near
Rockall
Rockall () is a high, uninhabitable granite islet in the North Atlantic Ocean. It is west of Soay, St Kilda, Scotland; northwest of Tory Island, Ireland; and south of Iceland.
The nearest permanently inhabited place is North Uist, east in ...
. It is one of the largest
single-celled organisms known, at up to across.
It was
first described in 1882 by the
oceanographer
Oceanography (), also known as oceanology, sea science, ocean science, and marine science, is the scientific study of the ocean, including its physics, chemistry, biology, and geology.
It is an Earth science, which covers a wide range of top ...
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 unicellular organism, single-celled organisms, members of a phylum or class (biology), class of Rhizarian protists characterized by streaming granular Ectoplasm (cell bio ...
.
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
nematode
The nematodes ( or ; ; ), roundworms or eelworms constitute the phylum Nematoda. Species in the phylum inhabit a broad range of environments. Most species are free-living, feeding on microorganisms, but many are parasitic. Parasitic worms (h ...
s. The single cell has no cell divisions but is
multinucleate
Multinucleate cells (also known as multinucleated cells or polynuclear cells) are eukaryotic cells that have more than one nucleus, i.e., multiple nuclei share one common cytoplasm. Mitosis in multinucleate cells can occur either in a coordinate ...
, having multiple
nuclei.
It is not known how the organism feeds or reproduces. It may be a
filter feeder
Filter feeders are aquatic animals that acquire nutrients by feeding on organic matters, food particles or smaller organisms (bacteria, microalgae and zooplanktons) suspended in water, typically by having the water pass over or through a s ...
, 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 organic compounds which include fats, waxes, sterols, fat-soluble vitamins (such as vitamins A, D, E and K), monoglycerides, diglycerides, phospholipids, and others. The functions of lipids include storing ...
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 in nature as the mineral barite, which is the main commercial source of ...
, known as
granellae
Granellae are barium sulfate crystals within the cytoplasm of xenophyophores, giant single-celled megafauna found in the eastern Pacific seafloor. Their formation and functionality are not well understood, but the crystals are generally accepted ...
, 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; Historically also known as , or as ; ) is a marginal sea of the western Pacific Ocean. It is located between Russia's Kamchatka Peninsula on the east, the Kuril Islands on the southeast, Japan's island of Hokkaido on the sou ...
at a depth of 3300 metres.
See also
*
Largest organisms
This article lists the largest organisms for various types of life and mostly considers extant species, which found on Earth can be determined according to various aspects of an organism's size, such as: mass, volume, area, length, height, or eve ...
References
External links
Article containing a photograph of a specimenfrom ''
New Scientist
''New Scientist'' is a popular science 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 organ ...
''
*
{{Taxonbar, from1=Q20672776, from2=Q3020957
Biota of Scotland
Foraminifera genera
Xenophyophorea