AnimaliaMelanosporalesCeratostomataceaeMarin-FelixYasminaGuarroJosepano-LiraJosé F.GarcíaDaniaillerAndrew N.StchigelAlberto M.Melanospora (Sordariomycetes, Ascomycota) and its relativesMycoKeys181220182018448112210.3897/mycokeys.44.29742 Microthecium retisporum Udagawa & Cain, Can. J. Bot. 47: 1926. 1970.Fig. 5H, N ≡ Sphaerodesretispora (Udagawa & Cain) P.F. Cannon & D. Hawksw., J. Linn. Soc., Bot. 84: 149. 1982. = Microtheciumretisporumvar.inferius Udagawa & Cain [as ‘inferior’], Can. J. Bot. 47: 1928. 1970. ≡ Sphaerodesretisporavar.inferior (Udagawa & Cain) P.F. Cannon & D. Hawksw., J. Linn. Soc., Bot. 84: 149. 1982. ≡ Sphaerodesinferior (Udagawa & Cain) D.W. Li & N.P. Schultes, in Schultes, Murtishi & Li, Fungal Biology 121: 901. 2017. = Microtheciumretisporumvar.retisporum Udagawa & Cain, Can. J. Bot. 47: 1926. 1970. ≡ Sphaerodesretisporavar.retispora (Udagawa & Cain) P.F. Cannon & D. Hawksw., J. Linn. Soc., Bot. 84: 149. 1982. Notes.

This species is characterized by non-ostiolate ascomata, reticulate citriform ascospores with apiculate germ pores, a phialidic asexual morph and presence of bulbils. For morphological comparison see Notes of Mi.beatonii.

Morphological features of the genus Microthecium. Microtheciumlevitum (FMR 10098). A Non-ostiolate ascoma E Asci G Ascospores K Ascospore (SEM). Microtheciumfayodii (FMR 12363). B Ostiolate ascomata F Ascospores O Variable shaped bulbils. Microtheciumfimicola (FMR 5483). C Detail of cellular neck M Ascospores (SEM) P Bulbil. Microtheciumquadrangulatum (CBS 112763T). D Crown of setae around the ostiole L Ascospore SEM. Microtheciumretisporum (NBRC 8366). H Ascospores N Asexual morph. Microtheciumjaponicum (FMR 12371) I Ascospores J Ascospore SEM. Microtheciumsepedonioides (FMR 11933) Q Bulbil. Scale bars: 50 μm (A, B, O); 20 μm (C, D); 10 μm (E–I, P, Q); 5 μm (J, L–N); 2.5 μm (K).