Citation: Pem D et al. (2019) Mycosphere Notes 275-324: A morphotaxonomic revision and typification of obscure Dothideomycetes genera (incertae sedis). Mycosphere 10(1), 1115–1246
Dothidasteromella Höhn., Sber. Akad. Wiss. Wien, Math.-naturw. Kl., Abt. 1 119: 421 (1910)
Epiphytic on leaf of Cinnamomum japonicum, forming large blackened circular areas 1–2 mm. Superficial hyphae, brown to dark brown, difficult to remove from the surface of host. Sexual morph: Thyriothecia superficial, erumpent from mycelia mass, solitary or gregarious, globose to subglobose, more or less carbonaceous, difficult to remove from the host surface, opening by linear or sometimes Y-shaped at the centre of the thyriothecium. Peridium comprising 2-layers, outer layer dark brown, inner layer hyaline, comprising cells of textura angularis. Hamathecium usually lacking pseudoparaphyses. Asci 8-spored, bitunicate, fissitunicate, oblong or subglobose, lacking a pedicel, apical region of asci usually with a thick opaque ocular chamber. Ascospores overlappingly bi-seriate, hyaline, ellipsoidal to fusoid, 1-septate, deeply constricted at the septum, upper cell broader and shorter than lower cell, verrucose. Asexual morph: Undetermined.
Type species – Dothidasteromella sepulta (Berk. & M.A. Curtis) Höhn. 1910
Notes – Dothidasteromella was introduced by Höhnel (1910) to accommodate Dothidasteromella sepulta as the type species. The genus is characterized by brown to dark brown superficial hyphae forming blackened circular areas, superficial carbonaceous thyriothecia, a peridium of textura angularis, oblong or subglobose 8-spored asci and hyaline to brown, 1-septate, ellipsoidal to fusoid ascospores. The genus Dothidasteromella was placed in the family Asterinaceae based on presence of subcuticular hypostromata and superficial hyphae without appressoria by Von Arx and Müller (1975). There are currently 13 epithets under the genus Dothidasteromella. Hongsanan et al. (2014) studied the isotype and holotype specimen and placed the genus in Dothideomycetes genera incertae sedis as the characters of the asci and ascospores were not clear. In this study, we re-observed the holotype specimen (F56756). Based on the morphological re-examination of the specimen, it is characterized by Y-shaped thyriothecia, 8-spored oblong to subglobose asci, lacking a pedicel and 1-septate brown ascospores which are typical of the genus Asterina, accommodated in Asterinaceae. We therefore, place the genus Dothidasteromella in Asterinaceae until molecular data becomes available for further confirmation.
Höhnel FV. 1910 – Fragmente zur Mykologie: XI. Mitteilung (Nr. 527 bis 573). Sitzungsberichte der Kaiserlichen Akademie der Wissenschaften Math.-naturw. Klasse Abt. I. 119, 617–679.
Hongsanan S, Li YM, Liu JK, Hofmann T et al. 2014 – Revision of genera in Asterinales. Fungal Diversity 68, 1–68.
Von Arx JA, Muller E. 1975 – A reevaluation of the bitunicate Ascomycetes with keys to families and genera. Studies in Mycology 9, 1–159.