''Calicium viride'', commonly known as the green stubble lichen, is a species of pin lichen in the family

Caliciaceae The Caliciaceae are a family of mostly lichen-forming fungi belonging to the class Lecanoromycetes in the division Ascomycota. Although the family has had its classification changed several times throughout its taxonomic history, the use of m ...

, and the

type species In 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 species that contains the biological type specimen( ...

of the genus ''

Calicium ''Calicium'' is a genus of leprose lichens. It is in the family Caliciaceae. The sexual reproduction structures are a mass of loose ascospores that are enclosed by a cup shaped exciple sitting on top of a tiny stalk, having the appearance ...

''. It is a common and widely distributed species in

temperate In geography, the temperate climates of Earth occur in the middle latitudes (23.5° to 66.5° N/S of Equator), which span between the tropics and the polar regions of Earth. These zones generally have wider temperature ranges throughout t ...

areas of the Northern Hemisphere and southern South America.

Taxonomy

It was described as a new species by

Christiaan Hendrik Persoon Christiaan Hendrik Persoon (1 February 1761 – 16 November 1836) was a German mycologist who made additions to Linnaeus' mushroom taxonomy. Early life Persoon was born in South Africa at the Cape of Good Hope, the third child of an immi ...

in 1794. ''Calcium viride'' is the

of the genus ''

''. The

common name In biology, a common name of a taxon or organism (also known as a vernacular name, English name, colloquial name, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; and is often contra ...

for the lichen in North America is "green stubble lichen". The ''Calicium viride'' group is the name of a clade of closely related species that all have ascomata supported on relatively large and sturdy stalks, and spores with a distinctive spiral ornamentation. This group also includes '' C. corynellum'', '' C. salicinum'', and '' C. quercinum'', as well as ''

Cyphelium lecideinum ''Cyphelium'' is a genus of crustose areolate lichens with cup-like apothecia filled with sooty black spores.Field Guide to California Lichens, Stephen Sharnoff, Yale University Press, 2014, The genus is in the family Caliciaceae . The genus ...

'', which lacks a stalk but also has spiral-striated spores.

Description

''Calicium viride'' has a greenish-yellow

thallus Thallus (plural: thalli), from Latinized Greek (), meaning "a green shoot" or " twig", is the vegetative tissue of some organisms in diverse groups such as algae, fungi, some liverworts, lichens, and the Myxogastria. Many of these organisms ...

with a granular texture that grows as a crust on the surface of its

substrate Substrate may refer to: Physical layers *Substrate (biology), the natural environment in which an organism lives, or the surface or medium on which an organism grows or is attached ** Substrate (locomotion), the surface over which an organism lo ...

. The small black stalks, 1.5–2.5 mm long and roughly 0.1–0.15 mm thick, support the spore-bearing structures: at the tip of each stalk is a ''capitulum''–a spherical

apothecium An ascocarp, or ascoma (), is the fruiting body ( sporocarp) of an ascomycete phylum fungus. It consists of very tightly interwoven hyphae and millions of embedded asci, each of which typically contains four to eight ascospores. Ascocarps are mo ...

. The capitula are black with a brownish underside. '' Calicium corynellum'' is a rarer species that is somewhat similar in appearance to ''C. viride'', but it grows on rock instead of wood or bark, and it has shorter stalks, typically 0.5–0.6 mm long. It contains the secondary chemicals

rhizocarpic acid Rhizocarpic acid is an organic compound with the molecular formula C28H23NO6 which has been isolated from the lichen ''Rhizocarpon geographicum'' and other lichens A lichen ( , ) is a composite organism that arises from algae or cyanobacter ...

and

epanorin Epanorin is a lichen secondary metabolite with the molecular formula C25H25NO6. Epanorin inhibits the proliferation of MCF-7 cancer cells. References Further reading * * Lichen products Biological pigments Amides Furanones Meth ...

Habitat and distribution

The lichen is common on the bark and wood of

conifer Conifers are a group of cone-bearing seed plants, a subset of gymnosperms. Scientifically, they make up the division Pinophyta (), also known as Coniferophyta () or Coniferae. The division contains a single extant class, Pinopsida. All ex ...

trees in

montane Montane ecosystems are found on the slopes of mountains. The alpine climate in these regions strongly affects the ecosystem because temperatures fall as elevation increases, causing the ecosystem to stratify. This stratification is a crucial ...

forests, but sometimes grows on

deciduous tree In the fields of horticulture and Botany, the term ''deciduous'' () means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed leaves, usually in the autumn; to the shedding of petals, a ...

References

{{Taxonbar, from=Q10509974 viride Lichen species Lichens described in 1794 Lichens of Asia Lichens of Europe Lichens of North America Lichens of South America Taxa named by Christiaan Hendrik Persoon