''Hypnum cupressiforme'', the cypress-leaved plaitmoss or hypnum moss, is a common and widespread

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

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 ...

belonging to the

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

Hypnum ''Hypnum'' is a genus of mosses belonging to the family Hypnaceae. The genus has cosmopolitan distribution. A common name sometimes used for ''Hypnum'' moss is "carpet moss". Distribution ''Hypnum'' species are found on all continents exce ...

''. It is found in all continents except

Antarctica Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean, it contains the geographic South Pole. Antarctica is the fifth-largest contine ...

and occurs in a wide variety of habitats and climatic zones. It typically grows on tree trunks, logs, walls, rocks and other surfaces. It prefers

acid In computer science, ACID ( atomicity, consistency, isolation, durability) is a set of properties of database transactions intended to guarantee data validity despite errors, power failures, and other mishaps. In the context of databases, a sequ ...

ic environments and is fairly tolerant of

pollution Pollution is the introduction of contaminants into the natural environment that cause adverse change. Pollution can take the form of any substance (solid, liquid, or gas) or energy (such as radioactivity, heat, sound, or light). Pollutants, the ...

. It was formerly used as a filling for pillows and mattresses; the association with sleep is the origin of the genus name ''Hypnum'' (from

Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...

Hypnos In Greek mythology, Hypnos (; Ancient Greek: means 'sleep') also spelled Hypnus is the personification of sleep; the Roman equivalent is known as Somnus. His name is the origin of the word hypnosis. Pausanias wrote that Hypnos was a dearest fr ...

''). It is a small to medium-sized moss about 2–10 cm long. It is pleurocarpous, having prostrate, creeping stems which form smooth, dense mats. The stems are branched and covered in overlapping leaves giving the impression of a

cypress Cypress is a common name for various coniferous trees or shrubs of northern temperate regions that belong to the family Cupressaceae. The word ''cypress'' is derived from Old French ''cipres'', which was imported from Latin ''cypressus'', the ...

tree. The stem leaves are long and thin measuring 1.0-2.1 mm by 0.3-0.6 mm. They are concave and sickle-shaped, tapering towards the tip. The branch leaves are smaller and narrower than those on the stems. The moss produces short, cylindrical and slightly curved capsules which contain the

spore In biology, a spore is a unit of sexual or asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores form part of the life cycles of many plants, algae, f ...

s. The capsules are 1.7-2.4 mm long and have a lid-like operculum measuring 0.6-0.9 mm. They are borne on reddish-brown stalks which are 1-2.5 cm long. The moss is

dioicous Dioicy () is a sexual system where archegonia and antheridia are produced on separate gametophytes. It is one of the two main sexual systems in bryophytes. Both dioicous () and monoicous gametophytes produce gametes in gametangia by mitosis rathe ...

, having separate male and female plants. ''Hypnum cupressiforme'' is a highly variable species and numerous

varieties Variety may refer to: Arts and entertainment Entertainment formats * Variety (radio) * Variety show, in theater and television Films * ''Variety'' (1925 film), a German silent film directed by Ewald Andre Dupont * ''Variety'' (1935 film), ...

have been described.

References

*Bryophyte Flora of North America
''Hypnum cupressiforme''
Accessed 22 July 2008. *Glime, Janice M. (2007)
Household and personal uses
,
Bryophyte Ecology
'. Accessed 22 July 2008. *Phillips, Roger (1994) ''Grasses, Ferns, Mosses & Lichens of Great Britain and Ireland, Macmillan, London. *Smith, A. J. E. (2004) ''The moss flora of Britain and Ireland'', 2nd ed., Cambridge University Press, Cambridge. {{Taxonbar, from=Q245867 Hypnaceae Plants described in 1801 Taxa named by Johann Hedwig