Superregnum: Eukaryota
Regnum: Fungi
Subregnum: Dikarya
Divisio: Ascomycota
Subdivisio: Pezizomycotina
Classis: Lecanoromycetes
Subclassis: Ostropomycetidae
Ordo: Pertusariales
Familia: Megasporaceae
Genus: Megaspora
Species: M. rimisorediata – M. verrucosa
Name
Megaspora (Clauzade & Cl. Roux) Hafellner & V.Wirth, 1987
Type: Megaspora verrucosa (Ach.) Hafellner & V.Wirth
References
Primary references
Hafellner & V. Wirth, in Wirth, Flechten Baden-Württemb. Verbr.-Atlas: 511 (1987)
Wirth, V. (1987) Die Flechten Baden-Wurttembergs. Eugen Ulmer, GmbH & Co., Stuttgart. 528 pp. **[RLL List # 133 / Rec.# 20390] - (Recent Literature on Lichens)**
References
Harada, H. (1997) Megaspora verrucosa (lichenized Ascomycetes; Megasporaceae) newly found in Japan. Hikobia 12: 221–225. **[RLL List # 174 / Rec.# 7744] - (Recent Literature on Lichens)**
Lumbsch, H.T.; Feige, G.B. and Schmitz, K.E. (1994) Systematic studies in the Pertusariales I. Megasporaceae, a new family of lichenized Ascomycetes. J. Hattori Bot. Lab. 75: 295–304. **[RLL List # 155 / Rec.# 11847] - (Recent Literature on Lichens)**
Nash III, T.H. and Ryan, B.D. (2007) Megaspora (pp. 244-245) In: Nash III, T.H., Gries, C., and Bungartz, F. (eds.), Lichen Flora of the Greater Sonoran Desert Region, Vol. 3. Lichens Unlimited, Arizona State University, Tempe, Arizona, 567 pages. **[RLL List # 210 / Rec.# 30227] - (Recent Literature on Lichens)**
Ozenda, P. and Clauzade, G. (1970) Les Lichens, Étude biologique et Flore illustrée. Paris: Masson & Cie, 801 pp. **[RLL List # 77 / Rec.# 14113] - (Recent Literature on Lichens)** (PDF file - 392 MB)
Purvis, O.W. and James, P.W. (1992) Megaspora Meyen (1843), PP. 366-377 in Purvis, O.W., Coppins, B.J., Hawksworth, D.L., James, P.W. and Moore, D.M. (eds.) The Lichen Flora of Great Britain and Ireland. London: Nat. Hist. Mus. Pub./Br. Lich. Soc. **[RLL List # 151 / Rec.# 15105] - (Recent Literature on Lichens)**
Megaspora in United States Department of Agriculture, Natural Resources Conservation Service, PLANTS Database.
Megaspora in Index Fungorum.
Megaspora in MycoBank.
Vernacular names
English: False sunken disk lichen; Megaspora lichen
Megaspora is a genus of lichen-forming fungi in the family Megasporaceae. It contains four species of crustose lichens that typically grow on soil, bryophytes (mosses and liverworts), or plant litter on chalky substrates.
Taxonomy
The genus was circumscribed by Georges Clauzade and Claude Roux in 1984 with M. verrucosa assigned as the type species.[2]
In 2012, Linda in Arcadia and Anders Nordin proposed to conserve the name Megaspora verrucosa (Ach.) Arcadia & A.Nordin against M. verrucosa Hafellner & V.Wirth due to taxonomic confusion stemming from historical errors in the original basionym citation.[3] The original introduction of Aspicilia subg. Megaspora erroneously cited Lecanora verrucosa Ach. as the basionym, when it should have been Urceolaria verrucosa Ach. This misattribution led to the invalid introduction of the name Megaspora verrucosa by Hafellner & Wirth based on the wrong species. To rectify this and prevent future taxonomic issues, the proposal suggested adopting M. verrucosa (Ach.) Arcadia & A.Nordin based on U. verrucosa Ach. as the conserved name, which the Nomenclature Committee for Fungi eventually recommended accepting after initially considering rejection.[4]
Description
Megaspora is a genus of crustose lichens, meaning they form a crust-like growth on their substrate. The thallus (lichen body) is non-lobate (lacking distinct lobes) and can appear somewhat powdery (pruinose). The photobiont, or photosynthetic partner, in this lichen is chlorococcoid, referring to a type of green algae.[5]
The reproductive structures of Megaspora are apothecia, which are deeply immersed in the thalline warts (small, wart-like structures on the thallus). The apothecia have a thalline margin, a rim composed of thallus tissue. The true exciple, or the outer layer surrounding the apothecia, is thin and either colourless or pale straw-coloured, consisting of tightly packed, vertically aligned hyphae (fungal filaments).[5]
The epithecium, the uppermost layer of the apothecium, is brown-green and turns bright green when treated with a nitrogen-based reagent (N+). The hymenium, the spore-bearing layer, is colourless and turns blue with iodine (I+). The hypothecium, the layer beneath the hymenium, is also colourless. The hamathecium, which contains the paraphyses (sterile filaments among the asci), is richly branched and interconnected (anastomosing) without swollen tips, and is strongly conglutinated (stuck together).[5]
The asci (spore-producing cells) are of the Biatora-type, containing 4 to 8 spores, and are clavate (club-shaped) or cylindric-clavate, with thin walls except towards the apex. The asci have a pale tholus (a thickened area at the tip) that reacts faintly with potassium/iodine (K/I). The ascospores are large, aseptate (without internal divisions), globose (spherical) to shortly ellipsoidal, colourless, and have uniformly thickened walls.[5]
Conidiomata (structures producing asexual spores) have not been observed in this genus. No lichen products have been detected through thin-layer chromatography.[5]
Habitat
Megaspora lichens typically grow on soil, bryophytes (mosses and liverworts), or plant litter on calcareous (chalky) substrates. They are rarely found growing on bark (corticolous).[5]
Species
Megaspora cretacea Gasparyan, Zakeri & Aptroot (2016)[6] – Armenia
Megaspora iranica Haji Moniri & S.Y.Kondr. (2017)[7] – Iran
Megaspora rimisorediata Valadb. & A.Nordin (2011)[8] – Iran
Megaspora verrucosa (Ach.) Arcadia & A.Nordin (2012)
References
Clauzade, G.; Roux, C. (1984). "Les genres Aspicilia Massal. et Bellemerea Hafellner & Roux". Bulletin de la Société Botanique du Centre-Ouest (in French). 15: 127–141.
Wirth, V. (1987). Die Flechten Baden-Württembergs. Verbreitungsatlas (in German). Stuttgart: Verlag Eugen Ulmer. p. 511. ISBN 978-3-8001-3305-5.
Arcadia, Linda in; Nordon, Anders (2012). "(2053) Proposal to conserve the name Megaspora verrucosa (Ach.) L. Arcadia & A. Nordin against M. verrucosa Hafellner & V. Wirth (lichenised Ascomycota)". Taxon. 61 (2): 464–465. doi:10.1002/TAX.612018. JSTOR 23210538.
May, Tom C.; Lendemer, James C. (2023). "Report of the Nomenclature Committee for Fungi: 22". Taxon. 72 (6): 1356–1363. doi:10.1002/tax.13099.
Cannon, P.; Nordin, A.; Coppins, B.; Aptroot, A.; Sanderson, N.; Simkin, J. (2023). Pertusariales: Megasporaceae, including the genera Aspicilia, Aspiciliella, Circinaria, Lobothallia, Megaspora and Sagedia. Revisions of British and Irish Lichens. Vol. 34. p. 11.
Zakeri, Zakieh; Gasparyan, Arsen; Aptroot, André (2016). "A new corticolous Megaspora (Megasporaceae ) species from Armenia". Willdenowia. 46 (2): 245–251. doi:10.3372/wi.46.46205.
Haji Moniri, M.; Gromakova, A.B.; Lőkös, L.; Kondratyuk, S.Y. (2017). "New members of the Megasporaceae (Pertusariales, lichen-forming Ascomycota): Megaspora iranica spec. nova and Oxneriaria gen. nova". Acta Botanica Hungarica. 59 (3–4): 343–370. doi:10.1556/034.59.2017.3-4.5.
Valadbeigi, Tahereh; Nordin, Anders; Tibell, Leif (2011). "Megaspora rimisorediata (Pertusariales , Megasporaceae), a new sorediate species from Iran and its affinities with Aspicilia sensu lato". The Lichenologist. 43 (4): 285–291. doi:10.1017/S0024282911000211.
Retrieved from "http://en.wikipedia.org/"
All text is available under the terms of the GNU Free Documentation License
