Stegonsporium acerophilum  

Anamorph: as for S. pyriforme, but conidia (29–)31–37(–40) x (13.5–)15–17.5(–18) µm, pyriform to cylindrical, with (3–)4–5(–6–7) transverse distosepta and often with 1 or rarely 2 longitudinal distosepta in 1–3 cells, light to dark brown, cell lumina lenticular or narrowly ellipsoidal, with a hyaline sheath to ca 2 µm thick.
Teleomorph: as for S. pyriforme, but stromata 0.7–1.5mm diam. Ostioles invisible from the bark surface, fusing within the ectostromatic disc. Ascomata (235–)270–400(–470) µm diam., (110–)140–230(–250) µm high. Paraphyses 3–8 µm diam., collapsing by maturity of the ascospores. Asci (145–)180–235(–255) x 26–32(–35) µm, narrowly clavate or ellipsoidal, the apex with a narrow cylindrical refractive ring, 8-spored. Ascospores (32–)34–40(–44) x (13.5–)14.5–17(–18) µm, ellipsoidal, medium to dark brown, with (3–)5 distosepta and 1 oblique or longitudinal distoseptum in 1 to several cells in  40–50 % of ascospores; with a short subglobose to irregular gelatinous appendage at each end, (2.5–)3–6(–8.5) µm long and (4–)6–10(–13.5) mm diam.