Schizotrema
| Schizotrema | |
|---|---|
Scientific classification 
| |
| Domain: | Eukaryota |
| Kingdom: | Fungi |
| Division: | Ascomycota |
| Class: | Lecanoromycetes |
| Order: | Graphidales |
| Family: | Graphidaceae |
| Genus: | Schizotrema Mangold & Lumbsch (2009) |
| Type species | |
| Schizotrema zebrinum Mangold (2009)
| |
| Species | |
|
S. flavolucens | |
Schizotrema is a genus of lichen-forming fungi in the family Graphidaceae. The genus was circumscribed in 2009 by Armin Mangold and H. Thorsten Lumbsch.[1]
Description
[edit]The genus Schizotrema consists of lichens with a thallus that can range from being immersed in the substrate to appearing more superficial. The thallus is usually pale in colour and often inconspicuous. Its photosynthetic partner, or photobiont, is a green alga from the genus Trentepohlia. The prothallus, a structure that sometimes surrounds the edges of the lichen, is faint and brown, blending subtly with the substrate. Some species produce soralia, which are small, discrete, and punctiform (dot-like) structures that release powdery reproductive propagules for asexual reproduction.[2]
The ascomata, or sexual reproductive structures are generally rounded and embedded within the thallus. These structures are surrounded by a thick, layered thalline rim, which may flake away as the lichen ages. The true exciple, the tissue surrounding the spore-producing region, is dark brown to black and multilayered. It may or may not react with iodine at its base (amyloid or non-amyloid) and is lined with small hair-like structures known as periphysoids.[2]
Internally, the hymenium (spore-producing region) is tightly packed and does not react to iodine staining (non-amyloid). The hamathecium, the network of sterile filaments within the hymenium, is composed of unbranched paraphyses with tips that are not thickened. The asci, which are sac-like structures where spores develop, are clavate (club-shaped) and contain between one and eight spores. These asci also do not react to iodine. The spores produced by Schizotrema are transversely septate (divided by cross-walls) or muriform (divided into multiple compartments by both transverse and longitudinal walls). They are hyaline (colourless) to yellowish, sometimes becoming brown at full maturity, and may have a thin gelatinous coating. Asexual reproductive structures called conidiomata have not been observed to occur in this genus.[2]
Species
[edit]- Schizotrema flavolucens (Sipman) Lücking (2016)[3]
- Schizotrema guadeloupense (Hale) Mangold & Lumbsch (2009)[1]
- Schizotrema quercicola (Coppins & P.James) Ertz, Frisch & Sanderson (2019)[4]
- Schizotrema schizolomum (Müll.Arg.) Mangold & Lumbsch (2009)[1]
- Schizotrema subzebrinum Mangold (2009)[1] – New South Wales
- Schizotrema vezdanum Kantvilas (2020)[5] – Tasmania
- Schizotrema zebrinum Mangold (2009)[1] – New South Wales
The species once known as Schizotrema cryptotrema (Nyl.) Rivas Plata & Mangold (2010) is now Cryptoschizotrema cryptotrema.[6]
References
[edit]- ^ a b c d e Mangold, A.; Elix, J.A.; Lumbsch, H.T. (2009). "Thelotremataceae". Flora of Australia. Vol. 57. Australian Biological Resources Study/CSIRO Publishing. pp. 653–659. ISBN 978-0-643-09664-6.
- ^ a b c Aptroot, A.; Weerakoon, G.; Cannon, P.; Coppins, B.; Sanderson, N.; Simkin, J. (2023). Ostropales: Graphidaceae, including the genera Allographa, Clandestinotrema, Crutarndina, Diploschistes, Fissurina, Graphis, Leucodecton, Phaeographis, Schizotrema, Thelotrema and Topeliopsis (PDF). Revisions of British and Irish Lichens. Vol. 36. p. 17.
- ^ Lücking, Robert; Mangold, Armin; Lumbsch, H. Thorsten (2016). "A worldwide key to species of the genera Myriotrema and Glaucotrema (lichenized Ascomycota: Graphidaceae), with a nomenclatural checklist of species published in Myriotrema". Herzogia. 29 (2): 493–513. doi:10.13158/heia.29.2.2016.493.
- ^ Ertz, Damien; Sanderson, Neil; Coppins, Brian J.; Klepsland, Jon T.; Frisch, Andreas (2019). "Opegrapha multipuncta and Schismatomma quercicola (Arthoniomycetes) belong to the Lecanoromycetes". The Lichenologist. 51 (5): 395–405. doi:10.1017/s002428291900029x.
- ^ Kantvilas, Gintaras (2020). "Tasmanian chroodiscoid thelotremoid lichens (Graphidaceae) revisited". Phytotaxa. 459 (3): 209–218. doi:10.11646/phytotaxa.459.3.2.
- ^ "Record Details: Schizotrema cryptotrema (Nyl.) Rivas Plata & Mangold, in Rivas Plata, Lücking, Sipman, Mangold, Kalb & Lumbsch, Lichenologist 42(2): 184 (2010)". Index Fungorum. Retrieved 30 January 2022.
