Melanospora (Sordariomycetes, Ascomycota) and its relatives Author Marin-Felix, Yasmina Author Guarro, Josep Author ano-Lira, Jose F. Author Garcia, Dania Author iller, Andrew N. Author Stchigel, Alberto M. text MycoKeys 2018 44 81 122 http://dx.doi.org/10.3897/mycokeys.44.29742 journal article http://dx.doi.org/10.3897/mycokeys.44.29742 1314-4049--81 Microthecium geoporae (W. Oberm.) Hoehn ., Sber. Akad. Wiss. Wien, Math.-naturw. Kl., Abt. 1 123: 98. 1914. Guttularia geoporae W. Oberm., Mykol. Zentbl. 3: 9. 1913. [Basionym] Notes. This species produces non-ostiolate ascomata and citriform, smooth-walled ascospores. Other species previously placed in Melanospora characterized by the production of non-ostiolate ascomata and smooth-walled ascospores are Mi. hypomyces , Mi. levitum and Mi. zobelii . Microthecium hypomyces is distinguished by its fusiform ascospores (citriform in the other species), and Mi. levitum by the presence of bulbils and a phialidic asexual morph. Microthecium geoporae and Mi. zobelii are distinguished by the size of their ascospores [28-30 x 12 -13(- 15) µm in Mi. geoporae and 18-25 x 8.5-12 x 6-9 µm in Mi. zobelii ]. Microthecium tenuissimum shows similar morphological features to these species but its ascospores are finely reticulate under SEM and its ascomata are smaller (less than 120 µm ) than in the other species.