Berlesiella nigerrima  

Anamorph: Exophiala-like in culture, described by Untereiner & Naveau (1999).
Teleomorph: ascostromata usually superficial on ostioles or stromata of members of Diatrypaceae, 400-550 µm diam. and 280-350 µm tall, pulvinate, matt black, the surface raised into rounded protuberances by emergent ostioles, covered in patches by short black aseptate thick-walled conical setae 10-16 long and 3-5 µm diam. at the base. Internal tissues of the stroma composed of thick-walled ± globose mid brown thick-walled cells in the basal region, merging into angular cells ± arranged in radiating lines. Ascomatal locules in a single layer, 55-80 µm diam. and 115-130 (-140) µm tall, wall tissues not differentiated. Interascal tissues absent, but apical downward-pointing hyphae apparently present. Asci 45-52 (-70) x 14-18 µm, the width greatly dependent on the extent of spore development, clavate, the apical part sometimes ± attenuated when young, thick-walled with rostrate dehiscence, 8-spored. Ascospores arranged biseriately, 13.7-17.5 (-18.9) x 5.2-6.2 µm, ± rhomboidal to ovoid-clavate, constricted at the septa to give a rather irregular outline, usually with five transverse septa and with one oblique longitudinal septum in one of the mid cells, pale grey-brown, strongly guttulate, thin-walled, smooth, without a gelatinous sheath.