''Calliergon cordifolium'' 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 Calliergonaceae family, commonly known as the calliergon moss (though this name refers to the genus ''

Calliergon ''Calliergon'' is a genus of moss in the order Hypnales Hypnales is the botanical name of an order of Bryophyta or leafy mosses. This group is sometimes called feather mosses, referring to their freely branched stems. The order includes mor ...

'' generally) or heart-leaved spearmoss. The species is abundant in the right habitat, and grows in marshes and wet woodland, especially woodland of

alder Alders are trees of the genus ''Alnus'' in the birch family Betulaceae. The genus includes about 35 species of monoecious trees and shrubs, a few reaching a large size, distributed throughout the north temperate zone with a few species ex ...

(''Alnus'') or

willow Willows, also called sallows and osiers, of the genus ''Salix'', comprise around 350 species (plus numerous hybrids) of typically deciduous trees and shrubs, found primarily on moist soils in cold and temperate regions. Most species are known ...

(''Salix''), as well as around streams, ditches and pools. The species grows in tufts among other moss species. ''Calliergon cordifolium'' requires a wet environment to grow, and often grows completely submerged in water. It typically prefers lowland, but has been recorded as high as above sea level in

Inverness Inverness (; ; from the , meaning "Mouth of the River Ness") is a city in the Scottish Highlands, having been granted city status in 2000. It is the administrative centre for The Highland Council and is regarded as the capital of the Highland ...

, Scotland. The species has a circumpolar Boreo-temperate distribution. It is found throughout Europe (including north, into the

Arctic Circle The Arctic Circle is one of the two polar circles, and the northernmost of the five major circle of latitude, circles of latitude as shown on maps of Earth at about 66° 34' N. Its southern counterpart is the Antarctic Circle. The Arctic Circl ...

Svalbard Svalbard ( , ), previously known as Spitsbergen or Spitzbergen, is a Norway, Norwegian archipelago that lies at the convergence of the Arctic Ocean with the Atlantic Ocean. North of continental Europe, mainland Europe, it lies about midway be ...

, the

Faeroe Islands The Faroe Islands ( ) (alt. the Faroes) are an archipelago in the North Atlantic Ocean and an autonomous territory of the Kingdom of Denmark. Located between Iceland, Norway, and the United Kingdom, the islands have a population of 54,609 ...

, Iceland and Greenland - and east into the

Caucasus The Caucasus () or Caucasia (), is a region spanning Eastern Europe and Western Asia. It is situated between the Black Sea and the Caspian Sea, comprising parts of Southern Russia, Georgia, Armenia, and Azerbaijan. The Caucasus Mountains, i ...

). It has been recorded in north and central Asia, as well as Turkey and Japan, throughout North America and in New Zealand. ''Calliergon cordifolium'' is a medium-sized to large moss with erect, green shoots. The shoots can reach up to , with egg-shaped leaves from wide. The leaves extend outwards, away from the stem. Towards the base, the leaves take on a heart shape, while, at the tip, they are rounded. The

spore In biology, a spore is a unit of sexual reproduction, sexual (in fungi) or asexual reproduction that may be adapted for biological dispersal, dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores fo ...

-bearing capsules are rarely seen, and are encountered only in spring or summer. The spores measure 10 to 16

micrometre The micrometre (English in the Commonwealth of Nations, Commonwealth English as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American English), also commonly known by the non-SI term micron, is a uni ...

s across. ''Calliergon cordifolium'' can be mistaken for similar species, including '' Calliergon giganteum'', '' Calliergonella cuspidata'', '' Straminergon stramineum'' and '' Pseudocalliergon trifarium''.

References

{{Taxonbar, from=Q5022106 Hypnales Flora of Bulgaria Flora of Europe Flora of temperate Asia Flora of Northern America Flora of New Zealand