Diplodia seriata  

Anamorph: conidiomata pycnidial, solitary or aggregated and sometimes confluent, immersed in the host, partially emergent at maturity, dark brown to black, ostiolate, non-papillate, thick-walled, outer layers composed of dark brown textura angularis, inner layers of thin-walled hyaline textura angularis. Conidiogenous cells 7-10(-12)  x 3-6 μm, hyaline, thin-walled, smooth, cylindrical to truncato-conical, proliferating percurrently with periclinal thickening or with 2-3 annellations. Conidia 22-27 × 11-15 μm, ovoid-cylindrical to cylindrical, usually widest in the middle, straight or slightly curved, the apex rounded and the base rounded to truncate and sometimes somewhat eccentric, initially hyaline, becoming dark brown, fairly thick-walled, the wall smooth externally, minutely roughened on the inner surface, mostly aseptatebut occasionally with a narrow ± median septum, without a gelatinous sheath or appendages.
Teleomorph: ascostromata immersed within cortical tissues, 400-600 µm diam, solitary or in  botryose clusters to 3 mm diam., globose but sometimes rather irregular in form, dark brown to black, with ostioles darker around the neck region, rather thick-walled. Interascal tissue absent. Asci 90–120 × 17–23 μm, clavate, short-stalked, thick-walled and fissitunicate with a conspicuous ocular chamber, 8-spored. Ascospores irregularly biseriate, 25–33 × 7–12 μm, fusiform to cylindric-fusiform and frequently slightly curved or geniculate, widest in the mid-region, hyaline, smooth, aseptate, rarely becoming 1-septate,  without a gelatinous sheath or appendages.