Malmidea | |
---|---|
Malmidea furfurosa | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Fungi |
Division: | Ascomycota |
Class: | Lecanoromycetes |
Order: | Lecanorales |
Family: | Malmideaceae |
Genus: | Malmidea Kalb, Rivas Plata & Lumbsch (2011) |
Type species | |
Malmidea piperis (Spreng.) Kalb, Rivas Plata & Lumbsch (2011) | |
Species | |
See text |
Malmidea is a genus of crustose lichens and the type genus of the family Malmideaceae. [1] It was established in 2011 to contain a phylogenetically distinct group of species formerly placed in the genus Malcolmiella . The crust-like thallus of Malmidea lichens has a surface that varies from smooth to rough, featuring textures such as verrucose (wart-like), granulose (grainy), or pustulate (pimpled). These textures are often formed by goniocysts , which are spherical clusters of green algal cells from the family Chlorococcaceae, encased in fungal hyphae. Malmidea comprises nearly 70 mostly tropical species that grow on bark, although a few grow on leaves.
Both the family Malmideaceae and the genus Malmidea were created in 2011 to accommodate a group of species, formerly placed in genus Malcolmiella (family Pilocarpaceae), that molecular phylogenetics showed to be a distinct lineage and worthy of recognition at the family level. Klaus Kalb, Eimy Rivas Plata, and H. Thorsten Lumbsch originally placed 37 species in the genus – 5 new species and 32 new combinations. [1] Many additional species have since been transferred to Malmidea from other genera, or described as new.
The generic name Malmidea honours Swedish botanist Gustaf Oskar Andersson Malme (1864–1937). [2]
The thallus of Malmidea lichens grow on bark (corticolous) or on leaves (foliicolous). The form of the thallus is like a crust, ranging in surface texture from smooth to verrucose (studded with wartlike protuberances), granulose (covered with small grains) or pustulate (covered with pustules). These variously shaped surface bumps are often formed by goniocysts (spherical aggregations of photobiont cells surrounded by short-celled hyphae) that develop on a whitish fibrous underlying prothallus. The photobiont partner of Malmidea is a member of Chlorococcaceae, a family of green algae. [1]
Malmidea apothecia are sessile, with a more or less rounded shape, and have a distinct margin. They have a biatorine form, meaning that they have only a pale, not blackened proper margin and always lack a margin on the thallus. The excipulum is usually paraplectenchymatous (a cell arrangement where the hyphae are oriented in all directions), made of radiating hyphae, partly with medullary layer or chambers composed of loosely arranged, periclinal hyphae (i.e. lined up in parallel adjacent to another layer of hyphae) with constricted septa and incrusted with hydrophobic granules. The hypothecium (the layer of hyphal tissue immediately beneath the hymenium) is prosoplectenchymatous (a cell arrangement where the hyphae are all oriented in one direction), and translucent to dark brown. Asci are club-shaped, lacking a distinct tubular structure in the tholus that is characteristic of family Pilocarpaceae. Ascospores usually number four to eight per ascus, and are colourless, ellipsoid, non-septate, and usually filled with oblong crystals. The spore walls are evenly thickened or thickened at the ends, and halonate (having a transparent outer layer). Conidia are threadlike and curved, measuring 17–25 by 0.8 μm. [1] Pycnidia are rare in this genus; they occur in the thallus warts and are whitish and spherical, about 0.1 mm in diameter. [3]
Secondary chemicals associated with Malmidea include atranorin, sometimes norsolorinic acid (as in M. piperis ), anthraquinones, biphenyls and many unknown xantholepinones. [1]
As of December 2023 [update] , Species Fungorum (in the Catalogue of Life) accept 68 species of Malmidea. [4] Malmidea mostly occurs in tropical rainforests. [5]
The Graphidaceae are a family of lichen-forming fungi in the order Graphidales. The family contains nearly a hundred genera and more than 2000 species. Although the family has a cosmopolitan distribution, most Graphidaceae species occur in tropical regions, and typically grow on bark.
Fissurina is a genus of lichenized fungi in the family Graphidaceae. It has about 160 species, most of which are found in tropical regions.
Diorygma is a genus of lichen-forming fungi in the family Graphidaceae. The genus was circumscribed by Franz Gerhard Eschweiler in 1824. Species of the genus are widely distributed in tropical and subtropical regions of the world.
Porina is a genus of lichens in the family Trichotheliaceae. A 2020 estimate places about 145 species in the widespread genus.
Leucodecton is a genus of lichen-forming fungi in the family Graphidaceae. The genus was circumscribed in 1860 by Swiss lichenologist Abramo Bartolommeo Massalongo, with Leucodecton compunctum assigned as the type species.
Chapsa is a genus of lichens in the family Graphidaceae. The genus was circumscribed by Italian lichenologist Abramo Bartolommeo Massalongo in 1860.
Thelotrema is a genus of lichen-forming fungi in the family Graphidaceae, the family to which all taxa in the former Thelotremataceae now belong.
Stegobolus is a genus of lichen-forming fungi in the family Graphidaceae.
Astrothelium is a large genus of corticolous (bark-dwelling) lichens in the family Trypetheliaceae. The genus is characterized by a corticate thallus and diverse ascomata structures, which can be simple, aggregated, or forming pseudostromata. Astrothelium is also notable for the carbonized walls of its ascomata, the so-called textura intricata arrangement of cells in these walls, and various forms of distoseptate, transparent spores.
Polymeridium is a genus of lichen-forming fungi in the family Trypetheliaceae. Species in the genus are corticolous (bark-dwelling) and typically occur in tropical areas.
Gustaf Oskar Andersson Malme was a Swedish botanist.
Malmideaceae is a family of crustose and corticolous lichens in the order Lecanorales. It contains eight genera and about 70 species.
Coenogonium is a genus of filamentous lichens in the monotypic family Coenogoniaceae. It has about 90 species. Most species are leaf-dwelling or grow on bark, although a few are known to grow on rocks under certain conditions, and some are restricted to growth on termite nests. The genus was circumscribed in 1820 by German naturalist Christian Gottfried Ehrenberg.
Allographa is a genus of script lichens in the family Graphidaceae. It has nearly 200 species. Formally circumscribed in 1824 by François Fulgis Chevallier, Allographa was formerly included in Graphis, but was upgraded to generic status in 2018 by lichenologists Klaus Kalb and Robert Lücking.
Rhabdodiscus is a genus of script lichens in the family Graphidaceae. It has 36 species.
Graphidales is an order of lichen-forming fungi in the class Lecanoromycetes. It contains 6 families, about 81 genera and about 2,228 species. Family Graphidaceae are the largest crustose family within Graphidales order comprising more than 2000 species, which are widely distributed in tropical and subtropical regions of the world.
Clandestinotrema is a genus of lichen-forming fungi in the family Graphidaceae. It has 17 species. They typically inhabit montane and cloud forest at higher elevations in the tropics.
Gintarasia is a genus of lichen-forming fungi in the family Graphidaceae. It has seven species, all of which are found in Australia. Gintarasia species are corticolous (bark-dwelling), crustose lichens with a thelotremoid form.