Malmidea

Malmidea
Malmidea furfurosa
Scientific classification Edit this 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.

Taxonomy

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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]

Description

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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]

Chemistry

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Secondary chemicals associated with Malmidea include atranorin, sometimes norsolorinic acid (as in M. piperis), anthraquinones, biphenyls and many unknown xantholepinones.[1]

Species

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Malmidea attenboroughii (holotype shown) is known from a single locality in Bolivia.

As of December 2023, Species Fungorum (in the Catalogue of Life) accept 68 species of Malmidea.[4] Malmidea mostly occurs in tropical rainforests.[5]

References

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  1. ^ a b c d e Kalb, K.; Rivas Plata, E.; Lücking, R.; Lumbsch, H.T. (2011). "The phylogenetic position of Malmidea, a new genus for the Lecidea piperis- and Lecanora granifera-groups (Lecanorales, Malmideaceae), inferred from nuclear and mitochondrial ribosomal DNA sequences, with special reference to Thai species". Bibliotheca Lichenologica. 106: 143–168.
  2. ^ Burkhardt, Lotte (2022). Eine Enzyklopädie zu eponymischen Pflanzennamen [Encyclopedia of eponymic plant names] (pdf) (in German). Berlin: Botanic Garden and Botanical Museum, Freie Universität Berlin. doi:10.3372/epolist2022. ISBN 978-3-946292-41-8.
  3. ^ a b c d e f g h i j k l Kalb, Klaus (2021). "New or otherwise interesting lichens mainly from Brazil and Venezuela with special reference to the genus Malmidea" (PDF). Archive for Lichenology. 27: 1–41.
  4. ^ "Malmidea". Catalogue of Life. Species 2000: Leiden, the Netherlands. Retrieved 12 December 2023.
  5. ^ a b c Breuss, Othmar; Lücking, Robert (2015). "Three new lichen species from Nicaragua, with keys to the known species of Eugeniella and Malmidea". The Lichenologist. 47 (1): 9–20. doi:10.1017/S0024282914000565.
  6. ^ Guzow-Krzemińska, B; Flakus, A; Kosecka, M; Jabłońska, A; Rodriguez-Flakus, P; Kukwa, M. (2019). "New species and records of lichens from Bolivia". Phytotaxa. 397 (4): 257–279. doi:10.11646/phytotaxa.397.4.1.
  7. ^ a b Aptroot, André; de Souza, Maria Fernanda; dos Santos, Lidiane Alves; Junior, Isaias Oliveira; Barbosa, Bruno Micael Cardoso; da Silva, Marcela Eugenia Cáceres (2022). "New species of lichenized fungi from Brazil, with a record report of 492 species in a small area of the Amazon Forest". The Bryologist. 125 (3): 435–467. doi:10.1639/0007-2745-125.3.433.
  8. ^ a b c Lücking, Robert; Álvaro-Alba, Wilson Ricardo; Moncada, Bibiana; Marín-Canchala, Norida Lucia; Tunjano, Sonia Sua; Cárdenas-López, Dairon (2023). "Lichens from the Colombian Amazon: 666 taxa including 28 new species and 157 new country records document an extraordinary diversity". The Bryologist. 126 (2): 242–303. doi:10.1639/0007-2745-126.2.242.
  9. ^ Cáceres, Marcela Eugenia da Silva; Aptroot, André; Lücking, Robert (2017). "Sprucidea, a further new genus of rain forest lichens in the family Malmideaceae (Ascomycota)". Bryologist. 120 (2): 202–211. doi:10.1639/0007-2745-120.2.202.
  10. ^ a b c Kalb, Klaus; Buaruang, Kawinnat; Mongkolsuk, Pachara; Boonpragob, Kansri (2012). "New or otherwise interesting lichens. VI, including a lichenicolous fungus". Phytotaxa. 42: 35–47. doi:10.11646/phytotaxa.42.1.5.
  11. ^ a b Cáceres, Marcela Eugenia da Silva; Santos, Viviane Monique dos; Góes, Drielle Tavares de; Mota, Danyelle Andrade; Aptroot, André (2013). "Two new species of Malmidea from north-eastern Brazil". The Lichenologist. 45 (5): 619–622. doi:10.1017/S0024282913000248.
  12. ^ Weerakoon, Gothamie; Aptroot, André (2014). "Over 200 new lichen records from Sri Lanka, with three new species to science". Cryptogamie, Mycologie. 35 (1): 51–62. doi:10.7872/crym.v35.iss1.2014.51.
  13. ^ Weerakoon, Gothamie; Wolseley, Patricia A.; Arachchige, Omal; Cáceres, Marcela Eugenia da Silva; Jayalal, Udeni; Aptroot, André (2016). "Eight new lichen species and 88 new records from Sri Lanka". Bryologist. 119 (2): 131–142. doi:10.1639/0007-2745-119.2.131.
  14. ^ Weerakoon, Gothamie; Aptroot, André (2013). "Some new lichen species from Sri Lanka, with a key to the genus Heterodermia in Sri Lanka". Cryptogamie, Mycologie. 34 (4): 321–328. doi:10.7872/crym.v34.iss4.2013.321.