''Thamnobryum angustifolium'', the Derbyshire feathermoss, is a species of

moss Mosses are small, non-vascular plant, non-vascular flowerless plants in the taxonomic phylum, division Bryophyta (, ) ''sensu stricto''. Bryophyta (''sensu lato'', Wilhelm Philippe Schimper, Schimp. 1879) may also refer to the parent group bryo ...

in the

Neckeraceae Neckeraceae is a moss family in the order Hypnales. There are about 200 species native to temperate and tropical regions. Most grow on rocks, or other plants. Description Members of the family are usually large and glossy plants with creeping st ...

family. It is

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

Derbyshire Derbyshire ( ) is a ceremonial county in the East Midlands of England. It borders Greater Manchester, West Yorkshire, and South Yorkshire to the north, Nottinghamshire to the east, Leicestershire to the south-east, Staffordshire to the south a ...

, England, being restricted to a single

SSSI A Site of Special Scientific Interest (SSSI) in Great Britain, or an Area of Special Scientific Interest (ASSI) in the Isle of Man and Northern Ireland, is a conservation designation denoting a protected area in the United Kingdom and Isle ...

, where the main colony covers about of a single rock face, with small subsidiary colonies nearby. Threats include disturbance from cavers and climbers, collection by bryologists, pollution of the spring in which it grows, and

desiccation Desiccation is the state of extreme dryness, or the process of extreme drying. A desiccant is a hygroscopic (attracts and holds water) substance that induces or sustains such a state in its local vicinity in a moderately sealed container. The ...

during periods of drought. Its natural

habitat In ecology, habitat refers to the array of resources, biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species' habitat can be seen as the physical manifestation of its ...

river A river is a natural stream of fresh water that flows on land or inside Subterranean river, caves towards another body of water at a lower elevation, such as an ocean, lake, or another river. A river may run dry before reaching the end of ...

s. Because of its extreme rarity and localised occurrence, the species has its own individual Biodiversity Action Plan and is included on a list of the world's most threatened bryophytes. The plant is similar to the common ''

Thamnobryum alopecurum ''Thamnobryum alopecurum'' is a species of moss belonging to the family Neckeraceae. References

{{Taxonbar, from=Q442329 Neckeraceae ...

'', but can be distinguished from it by the structure of the branch leaves, which are narrower, very strongly toothed, parallel-sided and have a broad nerve. The leaves of ''T. cataractarum'' are less strongly toothed but they have an even broader nerve.

References

Endemic flora of England Neckeraceae Critically endangered plants Environment of Derbyshire Taxonomy articles created by Polbot {{hypnales-stub