''Polytrichum hyperboreum'' (commonly referred to as Arctic haircap moss"Polytrichum hyperboreum Arctic Haircap Moss".(2022) ''NatureServe Explorer''. Accessed 04-05-2022. https://explorer.natureserve.org/Taxon/ELEMENT_GLOBAL.2.126034/Polytrichum_hyperboreum) is a species of moss belonging to the genus ''

Polytrichum ''Polytrichum'' is a genus of mosses — commonly called haircap moss or hair moss — which contains approximately 70 species that cover a cosmopolitan distribution. The genus ''Polytrichum'' has a number of closely related sporophytic character ...

'', commonly found throughout arctic regions of the world."Polytrichum hyperboreum in Flora of North America" (2008). Published on the Interne
http://efloras.org
ccessed 05 April 2022' Missouri Botanical Garden, St. Louis, MO & Harvard University Herbaria, Cambridge, MA. http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=250065138 Members of this

dioecious Dioecy (; ; adj. dioecious , ) is a characteristic of a species, meaning that it has distinct individual organisms (unisexual) that produce male or female gametes, either directly (in animals) or indirectly (in seed plants). Dioecious reproductio ...

species readily produces sporophytes with their

sporophytic A sporophyte () is the diploid multicellular stage in the life cycle of a plant or alga which produces asexual spores. This stage alternates with a multicellular haploid gametophyte phase. Life cycle The sporophyte develops from the zygote pr ...

structure, consisting of a foot, seta, capsule, and a hairy calyptra, similar to other ''Polytrichum'' species. ''Polytrichum hyperboreum'' is distinguishable by certain unique features of there

gametophytic A gametophyte () is one of the two alternation of generations, alternating multicellular organism, multicellular phases in the life cycles of plants and algae. It is a haploid multicellular organism that develops from a haploid spore that has on ...

structure that sets them apart from other genus members.

Distribution and habitat

''Polytrichum hyperboreum'' has been found to inhibit arctic regions in North America including Greenland, Yukon, Alaska, Newfoundland and Labrador, Northwest Territories, Nunavut, Quebec, as well as in European and Asian countries such as Norway, Scandinavia and Russia.Tuba, Zoltán, Nancy G. Slack, and Lloyd R. Stark, eds. “Bryophyte Physiological Processes in a Changing Climate: an Overview.” Chapter. In ''Bryophyte Ecology and Climate Change'', 13–32. Cambridge: Cambridge University Press, 2011.https://doi.org/10.1017/CBO9780511779701.003 Ideal habitat for this species consists of acidic soil or sand, dry areas such as

tundra In physical geography, tundra () is a type of biome where tree growth is hindered by frigid temperatures and short growing seasons. The term ''tundra'' comes through Russian (') from the Kildin Sámi word (') meaning "uplands", "treeless moun ...

s or rocky areas, or alongside bodies of water, at elevations of roughly 0–1500 meters.

Sporophytic features

The sporophytic features of ''P. hyperboreum'' are common to other members of its genus. Key features that set the Polytrichum genus apart from others, such as light brown nematodontous peristome teeth and a hairy calyptra(hence the common name for the genus "hair-cap mosses"), are found many

species, including ''P. hyperboreum'' This species is also characterized by its relatively short, reddish setae, which is similar to the setae found on the species ''

Polytrichum commune ''Polytrichum commune'' (also known as common haircap, great golden maidenhair, great goldilocks, common haircap moss, or common hair moss) is a species of moss found in many regions with high humidity and rainfall. The species can be exceptional ...

''.

Gametophytic features

''Polytrichum hyperboreum'' has many gametophytic structures common to other members of the ''Polytrichum'' genus, however it also has certain unique structures that make this species identifiable from others. The basic structure of this plant that is visible to the naked eye consists of a stem (under 10 cm tall) containing hydroids and leptoids, with whitish rhizoids at the base, as well as a crowding of leaves in the

distal Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position pro ...

portion of the stem.Glime, J. M. 2017. Bryophyta - Andreaeopsida, Andreaeobryopsida, Polytrichopsida. Chapt. 2-6. In: Glime, J. M. Bryophyte Ecology. 2-6-1 Volume 1. Physiological Ecology. Ebook sponsored by Michigan Technological University and the International Association of Bryologists. Last updated 3 June 2020 and available at https://digitalcommons.mtu.edu/bryophyte-ecology/ The leaves themselves are costate, with a linear-lanceolate shape and infolded margins. These leaves become erect and tight together when dried, or erect and spread when moist. The species ranges in color from green at youth, to a chestnut brown colour after maturing. One of the most unique characteristics of this plant that is visible in the cross section of the leaf is the laminae. Unlike other species in its genus, ''P. hyperboreum'' has marginal laminae that wrap completely around the vertical lamellae of the leaf, completely enclosing them. Other ''Polytrichum'' species have both lamellae and laminae, however the laminae are not long enough to enclose the lamellae, leaving them exposed. The most distinct features to this species that sets it apart from other ''Polytrichum'' members include the plant's branching pattern, their unique awn, the cells of the lamellae and the overlapping marginal laminae.

References

Polytrichaceae {{Improve categories, date=May 2022