Sarcogyne Crustacea

''Sarcogyne'' is a genus of crustose lichens in the family Acarosporaceae. It was circumscribed by German botanist Julius von Flotow in 1850. A proposal has been put forth in 2021 to assign '' Sarcogyne clavus'' as the type species of the genus, "as it represents the original concept of Sarcogyne as having melanized lecideine apothecia without algae in the margin".

Description

Genus ''Sarcogyne'' includes lichens with a crust-like (crustose) thallus that can be cracked into small, island-like sections called , which are either broadly attached or have a thick fungal base. Sometimes, the thallus is , meaning it has small, scale-like structures with a stalk less than half the width of the scale.

The upper surface, or , of these lichens can vary from absent to quite thick and often gives the lichen a shiny appearance, especially in species found in dry or hot habitats. This shiny layer is particularly common in xerothermic or arid environments. The cortex, which forms the outer layer of the thallus, consists of fungal threads (hyphae) and/or round or irregular cells. The upper part of the cortex is pigmented, while the lower part is colourless and sometimes contains crystal formations visible under polarized light. These crystals can come from the lichen's own secondary metabolites or from the it grows on, especially if it is limestone.

The upper surface of ''Sarcogyne'' lichens is typically smooth or slightly wrinkled, and usually ranges in colour from pale to reddish-brown to black-brown, and occasionally rust-coloured. Some species may have a powdery coating (). Cracks often form in the thallus, leading to the lichen's replication through division. The photosynthetic partner () in these lichens is of the type, forming a continuous or occasionally interrupted under the surface.

The lower cortex can be either present or absent. The fruiting bodies (ascomata) of ''Sarcogyne'' are typically apothecia, which are disk-shaped structures that can be immersed in the thallus or elevated. These can appear (with a margin that looks like the thallus) or (with a distinct margin). The disk is usually red-brown to black-brown, smooth or wrinkled, sometimes with a powdery coating or pigment build-ups.

Inside the apothecia, the consists of numerous thin to stout, often branched filaments (paraphyses). The asci, which produce spores, typically contain over 100 spores and are club-shaped. The spores are usually spherical to ellipsoidal, colourless, and generally small, not exceeding 6 μm in length, except for '' Sarcogyne macrocarpa''.

''Sarcogyne'' lichens also produce conidiomata (pycnidia), which are small, immersed structures that produce asexual spores. The conidia are small and ellipsoidal to roughly spherical in shape. Chemically, ''Sarcogyne'' species often do not produce lichen products detectable by thin-layer chromatography , but may rarely contain gyrophoric or norstictic acid, which can usually be detected with spot tests.

Species

, Species Fungorum accepts 26 species of ''Sarcogyne''.

*'' Sarcogyne albothallina''
*'' Sarcogyne alcesensis''
*'' Sarcogyne arenosa''
*'' Sarcogyne bernardinensis''
*'' Acarospora brodoana''
*'' Sarcogyne brunnea'' – Australia
*'' Sarcogyne canadensis''
*'' Sarcogyne canberrensis''
*'' Sarcogyne clavus''
*'' Sarcogyne convexa''
*'' Sarcogyne crustacea''
*'' Sarcogyne desolata''
*'' Sarcogyne endopetrophila''
*'' Sarcogyne hypophaea''
*''Sarcogyne iridana'' – Australia
*'' Sarcogyne lapponica''
*'' Sarcogyne magnispora'' – Turkey
*'' Sarcogyne maritima'' – Australia
*'' Sarcogyne meridionalis'' – Australia
*'' Sarcogyne mitziae''
*'' Sarcogyne molongloensis'' – Australia
*'' Sarcogyne oceanica''
*'' Sarcogyne paradoxa''
*'' Sarcogyne parviascifera''
*'' Sarcogyne porphyricola'' – Australia
*'' Sarcogyne praetermissa'' – Europe
*'' Sarcogyne pruinosa''
*'' Sarcogyne reebiae''
*''Sarcogyne regularis''
*'' Sarcogyne saphyniana'' – China
*'' Sarcogyne sekikaica'' – Australia
*'' Sarcogyne similis''
*'' Sarcogyne squamosa''
*'' Sarcogyne terrulenta'' – Australia
*'' Sarcogyne tholifera'' – Australia
*'' Sarcogyne ulleungdoensis''
*'' Sarcogyne wheeleri''

Gallery

Image:Sarcogyne_regularis_(EU1).jpg, ''Sarcogyne regularis'' (section of apothecium; reddish part parasitized, hyaline normal)

References

{{Taxonbar, from=Q10661786

Acarosporales
Lecanoromycetes genera
Lichen genera
Taxa named by Julius von Flotow
Taxa described in 1850