Phacidiella P. Karst.

Wei, De-Ping, Gentekaki, Eleni, Wanasinghe, Dhanushka N., Hyde, Kevin D., To-Anun, Chaiwat & Cheewangkoon, Ratchadawan, 2022, Taxonomy and morphology of Phacidiella kunmingensis sp. nov. (Stictidaceae) from southwest China, Phytotaxa 573 (1), pp. 70-84 : 75

Phacidiella P. Karst. , Hedwigia 23: 85 (1884) amended

Saprobic on various plants i.e. Asteraceae ( Artemisia vulgaris ), Rubiaceae ( Asperula asperne ), Myrtaceae ( Eucalyptus sp. ), Podocarpaceae ( Podocarpus latifolius ), Salicaceae ( Salix caprea , S. viminalis ), and Vitaceae ( Vitis vinifera ) ( Li et al. 2020). Sexual morph: Apothecia clustered, immersed, cupulate, opening by a finely large pore. Margin entire to lacerate, white-pruinose, turnup outward. Disc deeply immersed, yellow, splitting away from the margin when dry. Exciple, four-layered; 1) prominent accessory thalline margin, 2) wall extended from subhymenium, of hyaline, thickwalled cell of textura angularis, 3) crystalliferous layer where crystals are abundant particularly in the upper part and 4) compact periphysoidal layer that perpendicularly lined with the crystalliferous layer. Subhymenium comprised of hyaline, angular cells, J-. Paraphyses filiform, numerous, aseptate, apically branched, enlarged, circinate, J- or faintly J +, not gelatinous, as long as asci. Asci eight-spored, cylindrical, slightly tapering toward the base, thick-walled, with a thick apex. Ascus cap round, pierced by a pore. Ascospores filiform, multiseptate, flexuous, non-disarticulating, no contraction at septa. Asexual morph: see Sutton (1980) and Li et al. (2020).

Type species: Phacidiella salicina P. Karst., Hedwigia 23: 85 (1884)

Notes: The nomenclature and composition of Phacidiella have been subjected to multiple revisions and ultimately six asexual species remain in this genus ( Smerlis 1962, Li et al. 2020). Historically, the sexual morph of Phacidiella has been linked to Phacidiopycnis (syn. Potebniamyces ) ( Smerlis 1962, Johnston et al. 2014) and Pyrenopeziza ( Sutton 1980) , but these connections have not been verified by cultures and molecular data. Potebniamyces is characterized by ellipsoidal to globose, carbonaceous apothecia, cylindrical asci and guttulate, aseptate, ellipsoidal-fusoid ascospores. Pyrenopeziza is a speciose genus, containing more than 300 epithets, while the comprehensive taxonomic analysis of this genus is lacking ( Crous et al. 2017). Pyrenopeziza was featured with blackish, cupulate, hairy apothecia, cylindricalclavate asci, aseptate, ellipsoidal-clavate ascospores ( Fuckel 1870). In this study, we have obtained a collection from China, which was isolated from its sexual morph. In the DNA-based sequence data analyses of combined ITS, LSU, mtSSU and rpb2 sequences, the new taxon forms a clade with P. alsophilae and P. podocarpi . Thus, we determine the taxonomic placement of our new taxa in this genus and amended the generic description to accommodate its sexual morphic characteristics. The ascospore morphology of our new species is filiform, multiseptate, dramatically differing from those in Phacidiopycnis and Pyrenopeziza . The findings suggest that Phacidiella is not congeneric with Phacidiopycnis and Pyrenopeziza .