''Linea'' () is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

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 ...

belonging to the subfamily Rhabdammininae. It is a

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unisp ...

genus containing the sole species ''Linea simplex'' (). It was described in 1989 from samples of foraminifera collected at the Nares Abyssal Plain. The test of the organism consists of a flexible unbranched tube, several centimiters long, with a diameter of around 80 μm.

Etymology

The generic name comes from the

Latin Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...

noun ''

linea ''Linea'' () is a genus of foraminifera belonging to the subfamily Rhabdammininae. It is a monotypic genus containing the sole species ''Linea simplex'' (). It was described in 1989 from samples of foraminifera collected at the Nares Abyssal Pl ...

'' meaning string, due to the string-like appearance of the organism. The

specific epithet In Taxonomy (biology), taxonomy, binomial nomenclature ("two-term naming system"), also called binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin gramm ...

comes from the Latin adjective ''

simplex In geometry, a simplex (plural: simplexes or simplices) is a generalization of the notion of a triangle or tetrahedron to arbitrary dimensions. The simplex is so-named because it represents the simplest possible polytope in any given dimension. ...

'' meaning plain, simple.

Description

''Linea simplex'' has an overall string-like appearance, with a thin unbranching test in the shape of a flexible tube with a consistent diameter of around 80 μm. The tube is several centimeters long, irregularly filled by dark material, presumably stercomata. It is morphologically reminiscent of the genus '' Dendrophrya'', but differs in being unbranched. It also has similarities with '' Bathysiphon'', but is smaller in diameter and has a much thinner wall section. The full organism measures several centimeters.

Taxonomy

The

''Linea'' was described in 1989 by

paleontologist Paleontology, also spelled as palaeontology or palæontology, is the scientific study of the life of the past, mainly but not exclusively through the study of fossils. Paleontologists use fossils as a means to classify organisms, measure geolo ...

s Claudia J. Schröder, F. S. Medioli and D. B. Scott, as part of a survey on the

benthic The benthic zone is the ecological region at the lowest level of a body of water such as an ocean, lake, or stream, including the sediment surface and some sub-surface layers. The name comes from the Ancient Greek word (), meaning "the depths". ...

l community of the Nares Abyssal Plain, located in the western

North Atlantic Ocean The Atlantic Ocean is the second largest of the world's five oceanic divisions, with an area of about . It covers approximately 17% of Earth's surface and about 24% of its water surface area. During the Age of Discovery, it was known for se ...

. They studied and identified abyssal foraminifera collected in 1984 during a sampling program of the Dutch Seabed Working Group, and their identifications were based solely on 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) ...

morphology Morphology, from the Greek and meaning "study of shape", may refer to: Disciplines *Morphology (archaeology), study of the shapes or forms of artifacts *Morphology (astronomy), study of the shape of astronomical objects such as nebulae, galaxies, ...

. They identified a total of 20 new species, including ''Linea simplex'', which they assigned as the

type species In International_Code_of_Zoological_Nomenclature, zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the spe ...

of the genus ''Linea''. The authors were unable to take a photograph of the organism due to its long, narrow and springy tubular chamber that could not stay coiled and fit under any

microscope objective In optical engineering, an objective is an optical element that gathers light from an object being observed and focuses the light rays from it to produce a real image of the object. Objectives can be a single lens or mirror, or combinations of ...

. As the species is morphologically so simple, they decided to publish an illustration of the

holotype A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of s ...

. The holotype, measuring 13.3 mm, was recovered from the Nares Abyssal Plain at a depth of 5775 meters and was collected by Claudia Schröder. Its illustration was deposited at the

National Museum of Natural History The National Museum of Natural History (NMNH) is a natural history museum administered by the Smithsonian Institution, located on the National Mall in Washington, D.C., United States. It has free admission and is open 364 days a year. With 4.4 ...

with the registration number 430206. Upon its description, the genus ''Linea'' was classified in the subfamily Rhabdammininae, together with the genera '' Marsipella'' and '' Rhabdammina''.

References

{{Taxonbar, from1=Q115152311, from2=Q23757783 Monothalamea