Thyrostroma Höhn., Sber. Akad. Wiss. Wien, Math.-naturw. Kl., Abt. 1 120: 472 (1911)

Index Fungorum number: IF10224

Thyrostroma was introduced by Hӧhnel (1911) and typified with T. compactum. This genus was characterized by sexual morphs having immersed, globose to subglobose ascomata, clavate asci, fusiform to ellipsoidal, pale brown ascospores with 1 transverse septum; asexual morphs with immersed to erumpent sporodochium, clavate, ellipsoidal, obpyriform, subglobose, or oblong to subcylindric-clavate, phragmosporous to muriform, pale to dark brown conidia (Senwanna et al. 2019a). There are 25 Thyrostroma species listed in Index fungorum (2020), but only 12 species have been confirmed by molecular data. The most recent introduction to genus is Thyrostroma alhagi (Hyde et al. 2020c). In this study, we report Thyrostroma ulmeum, a new species and Ulmus minor as a new host for Thyrostroma ulmicola.