Yoshinagaia quercus Henn., Hedwigia 43(2): 143 (1904)
≡ Japonia quercus Höhn., Sber. Akad. Wiss. Wien, Math.-naturw. Kl., Abt. 1 118: 880 [69 repr.] (1909)
Saprobic on leaf of Quercus glauca (Fagaceae). Sexual morph: Ascomata 1–1.5 mm diam., up to 800 µm high, dark brown to black, superficial, epiphyllous, scattered or sometimes gregarious, discoid, with a short stipe, unilocular, glabrous, thick-walled, lacking an ostiole, but opening by an irregular rupture of upper wall. Peridium up to 100 µm thick, upper and lateral wall composed of textura angularis with relatively thick-walled, dark brown, verruculose cells and basal stroma pulvinate, of textura prismatica with thick-walled, dark brown cells in the outer layers, becoming paler towards inner layer. Hamathecium absent. Asci 150–220 × 25–30 µm, 8-spored, bitunicate, fissitunicate, cylindrical, with a short-stalk. Ascospores 22–30 × 10–13 µm, hyaline, ovoid with obtuse ends, unicellular, smooth-walled (adapted from Sivanesan & Hsieh 1995). Asexual morph: Conidiomata 800–1100 µm diam., 280–500 µm high, dark brown to black, pycnidial, epiphyllous, solitary to gregarious or confluent, superficial, with a very short stipe, globose to discoid, unilocular, glabrous, somewhat rough on the exterior. Ostiole absent, dehiscence by irregular splits in the apical wall. Conidiomatal wall 50–130 µm wide, composed of pulvinate, thick-walled, dark brown cells of textura prismatica in basal part, gradually merging with pale brown to hyaline cells towards the conidia hymenium, becoming thick-walled, dark brown, verruculose cells of textura angularis in upper and lateral part. Conidiophores arising from the innermost layers of basal wall, hyaline, branched, septate, smooth-walled. Conidiogenous cells 12–40 × 2–4 µm, hyaline, holoblastic, cylindrical, usually integrated, indeterminate, smooth-walled. Conidia 33–50 × 7.5–10 µm ( = 44 × 8 µm; n = 30), hyaline, smooth-walled, guttulate, composed of conidium body and an apical appendage delimited by a septum; conidium body clavate to fusiform, 3-septate, constricted at septa; central cell longer than apical and basal cell; basal cell subcylindrical, with a truncate base, straight or slightly curved; appendage unbranched up to a length of 10–40 µm long, then branching irregularly with 2–5, attenuated, flexuous branches.
Material examined: Japan, on leaf of Quercus glauca (Fagaceae), February 1910, P. Surreya (FH 01142399).
Li WJ, McKenZie EHC, Liu JK, Bhat DJ, Dai DQ, Caporesi E, Tian Q, Maharachcikumbura SSN, Luo ZL, Shang QJ, Zhang JF, Tangthirasunun N, Karunarathna SC, Xu JC, Hyde KD (2020) Taxonomy and phylogeny of hyaline-spored coelomycetes. Fungal Diversity 100: pages279–801.