The genus Scutula was circumscribed by French botanist Louis René Étienne Tulasne in 1862.[2] The limits of the generic circumscription as well as the limits of certain species in Scutula was confused for a long time.[3][4][5][6] In 1997, Triebel and colleagues applied the name Scutula specifically to a group of species growing on hosts of the Lecanorales suborder Peltigerineae, a monophyletic grouping of cyanobacteria-associated lichens.[7] Before this, Scutula was applied to a diverse set of unrelated lichenicolous fungi featuring hyaline spores with a single septum and sessile apothecia.[8]
Once classified in the family Micareaceae, molecular phylogenetic analysis showed Scutula to be nested within the Ramalinaceae, closely related to the genus Toninia.[9] This familial placement has been accepted in recent large-scale updates of fungal classifications.[10][11][12]
Description
Scutula species are characterized by apothecia that are either lecideine (where exciple forms the underside and outer layer of the apothecium, extending up to the rim, where it forms a darkened "proper margin") or biatorine (having a pale, not darkened proper margin and always lacking a thalline margin). The paraphyses are non-capitate (i.e., lacking a knob-like structure at the tip). Asci have a fuzzy amyloid (in Lugol's iodine solution after pre-treatment with KOH) axial tube structure of the ‘Scutula’-type. The ascospores are smooth, hyaline, and contain a single septum. Anamorphs associated with Scutula include Libertiella in the mesoconidia and Karsteniomyces in the macroconidia.[8]
^Hawksworth; D.L. (2003). "The lichenicolous fungi of Great Britain and Ireland: an overview and annotated checklist". The Lichenologist. 35 (3): 191–232. doi:10.1016/S0024-2829(03)00027-6.
^ abTriebel, D.; Wedin, M.; Rambold, G. (1997). "The genus Scutula (lichenicolous ascomycetes, Lecanorales): species on the Peltigera canina and P. horizontalis groups". Symbolae Botanicae Upsalienses. 32 (1): 323–337.
^ abWedin, Mats; Ihlen, Per G.; Triebel, Dagmar (2007). "Scutula tuberculosa, the correct name of the Scutula growing on Solorina spp., with a key to Scutula s. str. in the Northern Hemisphere". The Lichenologist. 39 (4): 329–333. doi:10.1017/S0024282907006949.
^Andersen, Heidi L.; Ekman, Stefan (2005). "Disintegration of the Micareaceae (lichenized Ascomycota)—a molecular phylogeny based on mitochondrial rDNA sequences". Mycological Research. 109 (1): 21–30. doi:10.1017/S0953756204001625. PMID15736860.
^Lücking, Robert; Hodkinson, Brendan P.; Leavitt, Steven D. (2017). "The 2016 classification of lichenized fungi in the Ascomycota and Basidiomycota–Approaching one thousand genera". The Bryologist. 119 (4): 361–416. doi:10.1639/0007-2745-119.4.361. S2CID90258634.
^Wijayawardene, Nalin N.; Hyde, Kevin D.; Lumbsch, H. Thorsten; Liu, Jian Kui; Maharachchikumbura, Sajeewa S. N.; Ekanayaka, Anusha H.; Tian, Qing; Phookamsak, Rungtiwa (2018). "Outline of Ascomycota: 2017". Fungal Diversity. 88 (1): 167–263. doi:10.1007/s13225-018-0394-8. S2CID7485476.
^Etayo, J.; Triebel, D. (2010). "New and interesting lichenicolous fungi at the Botanische Staatssammlung München". The Lichenologist. 42 (3): 231–240. doi:10.1017/S0024282909990417.