Fungalpedia – Note 680, Dothidasteroma
Dothidasteroma Höhn.
Citation when using this data: D. S. Marasinghe et al. 2023 (in prep.) – Fungalpedia, Ascomycota.
Index Fungorum, Facesoffungi, MycoBank, GenBank., Fig. 1
Classification: Parmulariaceae, Asterinales, Dothideomycetidae, Dothideomycetes, Pezizomycotina, Ascomycota, Fungi
Colonies epiphyllous on leaves. Sexual morph: Ascomata scattered to confluent, superficial, shield-like, dark brown to black, carbonaceous, flattened, variable in shape, usually circular, brown to dark brown, confluent, opening by irregular fissures. Stromata subcuticular, intracuticular to intradermal, sparse to extensive, mostly one-layered; cells brown to dark brown. Upper wall composed of pale to dark brown radially arranged cells of textura prismatica. Hamathecium initially consists of hyaline, septate, filiform, branched, pseudoparaphyses becoming evanescent at the maturity. Asci 8-spored, thick-walled, bitunicate, clavate to broadly clavate, sessile and thick at apex. Ascospores 1–2-seriate, ellipsoidal to cylindrical, with rounded ends, initially hyaline becoming brown at maturity, guttulate, 1-septum, constricted at the septum, smooth thin-walled. Asexual morph: Undetermined.
Notes: Dothidasteroma was introduced by von Höhnel (1909) with the type species of D. pterygotae. It is characterized by having superficial, flat ascomata with irregular locules. Species of this genus are mainly identified by sub- cuticular effuse brown stromata, which give rise to super- ficial stromatic ascomata (Inácio et al. 2011). Dothidasteroma is morphologically similar to ascospores and stromata in Aulacostroma (Inacio et al. 2011). However, Dothidasteroma lacks superficial hyphae or hyphal strands while Aulacostroma has superficial mycelium with bulbous appressoria (Inacio et al. 2011). The effuse brown internal stroma with small peg-like columns of Mintera is morphologically related to Dothidasteroma. However, it differs from Dothidasteroma by superficial appressorial mycelium and radiating locules (Inácio et al. 2011).
Type species: Dothidasteroma maculosum (Berk.&Broome) Höhn., Sber. Akad. Wiss. Wien, Math.-naturw. Kl., Abt. 1 119: 429 (1910)
Other accepted species: species Fungorum – search Dothidasteroma.
Figure 1 – Dothidasteroma casuarinae. a Upper wall of thyriothecia. b Asci. c Ascospores. Scale bars: a–c = 10 µm. Redrawn from Swart (1988)
References
Höhnel FV 1909 – Fragmente zur Mykologie: IX. Mitteilung (Nr. 407 bis 467). Sitzungsberichte.
Entry by
Diana Sandamali Marasinghe, Center of Excellence in Fungal Research, Mae Fah Luang University, Chiang Rai, 57100, Thailand School of Science, Mae Fah Luang University, Chiang Rai, 57100, Thailand, Mushroom Research Foundation, 128 M.3 Ban Pa Deng T. Pa Pae, A. Mae Taeng, Chiang Mai, 50150, Thailand
Published online 29 August 2023