Scytinium | |
---|---|
Scytinium gelatinosum | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Fungi |
Division: | Ascomycota |
Class: | Lecanoromycetes |
Order: | Peltigerales |
Family: | Collemataceae |
Genus: | Scytinium (Ach.) Gray (1821) |
Type species | |
Scytenium palmatum (Huds.) Gray (1821) | |
Synonyms [1] | |
Scytinium is a genus of lichen-forming fungi in the family Collemataceae. [2] It has 49 species. [3] These lichens are typically found on basic rocks, soil, and trees, occasionally in association with mosses. Despite the morphological and ecological diversity within Scytinium, its species share similar ascospore features, such as shape and septation, as well as a small to medium-sized thallus with at least a partial cortex . [4]
Scytinium encompasses lichen species that exhibit a variety of thallus forms, such as crustose, squamulose, minutely foliose , or minutely shrubby . These lichens have a gelatinous texture, and their colour ranges from dark brown and bluish-grey to olive-green. The lobes of Scytinium can be spreading, elongate, or somewhat cylindrical in shape. The upper and lower cortex , when present, is composed of either cuboid cells or flattened, degraded tissue. The medulla contains loosely interwoven or compact hyphae, along with the photobiont Nostoc –a common genus of cyanobacteria. [4]
Both the upper and lower surfaces of Scytinium lichens can vary from smooth to wrinkled or ridged and typically exhibit a matte appearance. While isidia may or may not be present, soredia are absent in this genus. The photobiont cells are generally arranged in distinct chains. The ascomata are in the form of apothecia with a red-brown disc , which can be sessile, laminal, or marginal. The thalline margin is smooth to granulose , isidiate to lobulate , and often persistent. The true exciple is raised, cup-shaped, and predominantly composed of isodiametric cells, ranging in colour from colourless to reddish-brown. The disc is either concave or flat. [4]
The epithecium is colourless to reddish-brown and does not react with a solution of potassium hydroxide or ammonia. The hymenium is colourless, turning blue when exposed to iodine. The hypothecium is shallow, and its colour varies from colourless to pale yellowish. The hamathecium consists of numerous, conglutinate paraphyses that separate in potassium hydroxide and sometimes have branched apices that are somewhat swollen. The asci contain eight spores and are club-shaped (clavate), with a strongly thickened apex that reacts to potassium hydroxide and iodine, turning blue. Ascospores are primarily ellipsoidal, muriform , and colourless, lacking any distinct surface ornamentation or perispore . Conidiomata , or pycnidia , are infrequent in Scytinium species. No lichen products have been detected in Scytinium species using thin-layer chromatography. [4]
As of December 2024 [update] , Species Fungorum (in the Catalogue of Life) accepts 48 species of Scytinium. [2]
Collema is a genus of lichens in the family Collemataceae. The photobiont is the cyanobacterium genus Nostoc. Species in this genus typically grow on nutrient-rich bark or somewhat siliceous or calcareous rocks in humid environments.
The Pannariaceae are a family of lichens in the order Peltigerales. Species from this family have a widespread distribution, but are especially prevalent in southern temperate regions.
The Collemataceae are a family of mostly lichen-forming fungi in the order Peltigerales. The family contains twelve genera and about 325 species. The family has a widespread distribution.
Psoroma is a genus of lichen-forming fungi in the family Pannariaceae. The widespread genus contains about 30 species, most of which are found in south temperate regions.
Pannaria is a genus of lichen-forming fungi in the family Pannariaceae. The widespread genus contains an estimated 51 species, found primarily in tropical regions.
Phaeophyscia is a genus of lichen-forming fungi in the family Physciaceae.
Leptogium is a genus of lichen-forming fungi in the family Collemataceae. It has about 110 species. Species formerly classified under Leptogium have since been divided among the genera Leptogium, Pseudoleptogium, and Scytinium. Leptogium lichens are predominantly found on tree bark or soil, often among mosses, and sometimes on rocks in moist environments.
Arctomia is a genus of lichen-forming fungi in the family Arctomiaceae. The genus was originally circumscribed by Theodor Magnus Fries in 1861. Arctomia has a circumpolar distribution.
Nephroma is a genus of medium to large foliose lichens. The genus has a widespread distribution. They are sometimes called kidney lichens, named after the characteristic kidney-shaped apothecia that they produce on the lower surface of their lobe tips, which often curl upwards and thus are visible from above. Sterile specimens that do not have apothecia can look somewhat like Melanelia, Peltigera, Platismatia, or Asahinea. Most species grow either on mossy ground or rocks, or on trees.
Bryoria is a genus of lichenized fungi in the family Parmeliaceae. Many members of this genus are known as horsehair lichens. The genus has a widespread distribution, especially in boreal and cool temperate areas.
Stereocaulon is a genus of lichens. Members of Stereocaulon are commonly called rock foam lichens. Photobiont partners of Stereocaulon include green algae from the genera Asterochloris, Chloroidium, and Vulcanochloris. Stereocaulon is difficult to ID to species, but there is a high diversity of species within the genus.
Blennothallia is a genus of jelly lichens in the family Collemataceae. It has four species, which collectively have a cosmopolitan distribution.
Enchylium is a genus of lichen-forming fungi in the family Collemataceae.
Lathagrium is a genus of lichen-forming fungi in the family Collemataceae. It has 10 species of gelatinous lichens. Species in this genus typically grow on calcareous rocks, often amidst mosses, but can also be found on siliceous or serpentine rocks, mortar, or soil.
Rostania is a genus of lichen-forming fungi in the family Collemataceae. These lichens are primarily found on tree bark, occasionally on wood, with one species known to inhabit soil. The genus is characterized morphologically by having minute thalli made of hyphal tissue without a separate cortex, and the more or less cuboid-shaped ascospores.
Enchylium conglomeratum, commonly known as dotted jelly lichen, is a species of foliose lichen in the family Collemataceae. Formerly known as Collema conglomeratum, it was renamed in 2013. This lichen has a fragmented distribution across the Holarctic region, occurring in both North America and Europe.
Enchylium polycarpon, commonly known as the shaly jelly lichen, is a species of foliose lichen in the family Collemataceae. Formerly known as Collema polycarpon, it was renamed in 2013 as part of a taxonomic revision. This lichen has a widespread global distribution, occurring in various regions of North America, Europe, Africa, and Asia.
Enchylium limosum, commonly known as lime-loving tarpaper lichen, is a species of crustose to subfoliose lichen in the family Collemataceae. This unique lichen species possesses a gelatinous thallus with a dark coloration, contributing to its distinctive appearance. It thrives in a diverse array of habitats spanning temperate to boreal-montane regions, across Europe, North America, Africa, and Asia.
Callome is a fungal genus in the family Collemataceae. It consists of the single species Callome multipartita, a saxicolous (rock-dwelling), crustose lichen found in Northern Africa, Europe, and North America.