Microthecium beatonii D. Hawksw., Trans. Mycol. Soc. Japan 18: 145. 1977.

Marin-Felix, Yasmina, Guarro, Josep, ano-Lira, Jose F., Garcia, Dania, iller, Andrew N. & Stchigel, Alberto M., 2018, Melanospora (Sordariomycetes, Ascomycota) and its relatives, MycoKeys 44, pp. 81-122 : 81

Microthecium beatonii D. Hawksw., Trans. Mycol. Soc. Japan 18: 145. 1977.

≡ Sphaerodes beatonii (D. Hawksw.) P.F. Cannon & D. Hawksw., Bot. J. Linn. Soc. 84: 145. 1982.

Notes.

This species is characterized by non-ostiolate ascomata, 4-spored asci and very coarsely reticulate, citriform ascospores. These morphological features are also observed in Microthecium perplexum , but this species produces ascospores with only a third of the surface coarsely reticulate while the rest remains smooth-walled. Microthecium episphaerium and Mi. retisporum differ from Mi. beatonii in the production of 8-spored asci. Moreover, Mi. retisporum produces a phialidic asexual morph and bulbils, which are absent in the other mentioned species, and smaller ascospores (17-20 × 10-12 × 7-9 µm) than in Mi. beatonii [28 –34(– 40) × 14 –18(– 20) µm], in Mi. episphaerium (25-34 × 12-18 µm) and in Mi. perplexum (22-28 × 12-15 × 9-11 µm).