Aspidothelium

Aspidothelium is a genus of lichen-forming fungi in the family Thelenellaceae.^[1] All species in the genus have a tropical distribution and are crustose with a chlorococcoid photobiont partner. Most Aspidothelium species are foliicolous (leaf-dwelling), although some corticolous (bark-dwelling) species are known, as well as a single saxicolous (rock-dwelling) member.^[2]

Aspidothelium
Scientific classification
Domain:	Eukaryota
Kingdom:	Fungi
Division:	Ascomycota
Class:	Lecanoromycetes
Order:	Thelenellales
Family:	Thelenellaceae
Genus:	Aspidothelium Vain. (1890)
Type species
Aspidothelium cinerascens Vain. (1890)

Taxonomy

The genus was circumscribed by Finnish lichenologist Edvard August Vainio in 1890.^[3] Historically, it has at times been considered as a synonym of genus Thelenella. Families in which the genus has previously been classified are the Verrucariaceae, Strigulaceae, and the Aspidotheliaceae, a monogeneric family circumscribed especially to contain this genus.^[4] Modern molecular phylogenetic analysis has shown its placement in the family Thelenellaceae, allied with the order Ostropales.^[2]

Description

Aspidothelium is known for its production of perithecia that range in colour from whitish to pinkish or grey and are uncarbonized. These perithecia often exhibit wart-like, setae, or disc-like structures on their surface. Within the perithecia, dense and unbranched paraphyses and periphyses can be found alongside clavate asci and colourless ascospores. These ascospores are typically fusiform in shape, and muriform to transversely septate. Aspidothelium is particularly notable for its unique characteristic of producing fusiform ascospores with numerous transverse septa and short, broad cells.^[2]

Species

• Aspidothelium arachnoideum Lücking (2008) – Costa Rica
• Aspidothelium cuyabense (Malme) P.M.McCarthy (1995)
• Aspidothelium gemmiferum Sérus. & Lücking (2001)^[5] – Papua New Guinea
• Aspidothelium glabrum Lücking, Aptroot & Sipman (2008) – Costa Rica
• Aspidothelium hirsutum Yeshitela, Eb.Fisch., Killmann & Sérus. (2009)^[6] – Ethiopia
• Aspidothelium lueckingii Flakus (2009)^[7] – Bolivia
• Aspidothelium macrosporum (Müll.Arg.) Lücking (2008)
• Aspidothelium mirabile Lücking (1999)^[8] – Ecuador
• Aspidothelium ornatum Lücking (1999)^[8] – Ecuador
• Aspidothelium papillicarpum Lücking (2008) – Costa Rica
• Aspidothelium scutellicarpum Lücking (1999)^[8] – Ecuador
• Aspidothelium silverstonei Soto-Medina, Aptroot & Lücking (2017)^[9] – Colombia
• Aspidothelium submuriforme Aptroot, L.I.Ferraro & M.Cáceres (2014)^[10] – Argentina
• Aspidothelium trichothelioides Sérus. & Vězda (1978) – Africa & tropical America
• Aspidothelium verruculosum R.Sant. (1952) – tropical Asia & Australia

References

1. Wijayawardene, N.N.; Hyde, K.D.; Dai, D.Q.; Sánchez-García, M.; Goto, B.T.; Saxena, R.K.; et al. (2022). "Outline of Fungi and fungus-like taxa – 2021". Mycosphere. 13 (1): 53–453. doi:10.5943/mycosphere/13/1/2. hdl:10481/76378. S2CID 249054641.
2. Nelsen, M.P.; Lücking, R.; Cáceres, M.E.S.; Aptroot, A.; Lumbsch, H.T. (2016). "Assessing the phylogenetic placement and redundancy of Aspidotheliaceae (Ascomycota), an orphaned family of lichen-forming fungi". Systematics and Biodiversity. 15 (1): 63–73. doi:10.1080/14772000.2016.1203039. S2CID 89588251.
3. Vainio, E.A. (1890). "Etude sur la classification naturelle et la morphologie des lichens du Bresil. Pars secunda". Acta Societatis Pro Fauna et Flora Fennica (in Latin). 7 (2): 1256.
4. David, J.C.; Hawksworth, D.L. (1991). "Validation of six family names of lichenized ascomycetes". Systema Ascomycetum. 10: 1318.
5. Emmanuël, Sérusiaux; Lücking, Robert (2001). "Aspidothelium gemmiferum sp. nov., from Papua New Guinea (lichenized Ascomycetes)" (PDF). Mycotaxon. 79: 43–49.
6. Yeshitela, Kumelachew; Fischer, Eberhard; Killmann, Dorothee; Sérusiaux, Emmanuël (2009). "Aspidothelium hirsutum (Thelenellaceae) and Caprettia goderei (Monoblastiaceae), two new species of foliicolous lichens from Ethiopia and Kenya". The Bryologist. 112 (4): 850–855. doi:10.1639/0007-2745-112.4.850. S2CID 86816953.
7. Flakus, A. (2009). "Aspidothelium lueckingii: a new lichenized fungus from Bolivia". Nova Hedwigia. 88 (1–2): 139–143. doi:10.1127/0029-5035/2009/0088-0139.
8. Lücking, Robert (1999). "Foliicolous lichens and their lichenicolous fungi from Ecuador, with a comparison of lowland and montane rain forest". Willdenowia. 29 (1–2): 299–335. doi:10.3372/wi.29.2924. S2CID 85798499.
9. Medina, Edier Soto; Aptroot, André; Lücking, Robert (2017). "Aspidothelium silverstonei and Astrothelium fuscosporum, two new corticolous lichen species from Colombia". Cryptogamie, Mycologie. 38 (2): 253–258. doi:10.7872/crym/v38.iss2.2017.253. S2CID 90049963.
10. Aptroot, André; Ferraro, Lidia Itatí; Cáceres, Marcela Eugenia da Silva (2014). "New pyrenocarpous lichens from NE Argentina". The Lichenologist. 46 (1): 95–102. doi:10.1017/s0024282913000716. S2CID 88170280.