Didymellopsis (Sacc.) Clem. & Shear, Gen. fung., Edn 2 (Minneapolis): 66 (1931)
Index Fungorum number: IF 1550; Facesoffungi number: FoF 07656, 6 morphological species (Species Fungorum 2021), molecular data unavailable.
Lichenicolous on host. Sexual morph: Pseudothecia black, usually spherical, rarely pear-shaped, scattered, located on the periphery of the scales of the host or between them, deepened on ½ to completely immersed in tissue or rhizophytes, on the surface only black tips with a rounded outlet. Pseudothecial walls dark brown to brown-black, uniform as in the upper and in the lower parts, consist of 6–8 layers of pseudoparenchymal cells, pigmented amorphously, uniformly in the cell membranes of pseudothecia. Hymenial gelatin from I– to K / I–. Pseudoparaphyses numerous, branched and anastomosing. Asci bitunictae, thickened in the apical parts, with clear "ocular chamber", cylindrical to narrow-club-shaped, with an arrangement of ascospores in one, less often in two rows, I–. Ascospores 2-celled, hyaline, slightly narrowed at the base, without perisporia, the lower cell is slightly narrower than the upper, the tips slightly elongated. Asexual morph: Undetermined (Adapted from Khodosovtsev and Klymenko 2015).
Type species: Didymellopsis latitans (Nyl.) Sacc. ex Clem. & Shear
Notes: Didymellopsis was introduced by Saccado and validated by Clement and Shear (1931). Didymellopsis is characterized by spherical pseudothecia, bitunicate, cylindrical to narrow-club-shaped asci and hyaline 2-celled ascospores. Didymellopsis has lichenicolous habitat. Intraspecific differentiation in Didymellopsis is based on the size of ascospores, fruiting body and the existence of a certain kind of lichenized fungus. Phylogenetically, Didymellopsis is a distinct and well-supported genus in Xanthopyreniaceae.