Phaeostilbella atra  

Anamorph: conidiomata absent. Synnemata 150-450 µm high, the stipe narrow, 30-60 µm diam., black, arising from a basal stromatic knot of hyphae, head 45-105 µm diam., black. Marginal hyphae covering the stipe arising from the base, closely compacted and rarely branched, walls pale to dark olivaceous and usually smooth, without verrucose processes, tapered at the apex and forming a hyaline fringe around the spore mass, septate, cells 20-40 x 2.2-2.5 µm, tapering to ca 1 µm diam. at the apex. Conidiophores closely compacted in the stipe with the marginal hyphae and difficult to separate, branched several times with usually 2 branches at each node, spreading at the apex, hyaline or olivaceous, septate. Conidiogenous cells in whorls of 2-3, 15-35 x 1.5-2.5 µm, cylindrical, hyaline but often with a darkened collarette, proliferating percurrently. Conidia 10-13.5 x 2.5-3.5 µm, narrowly fusiform, the apex acute and the base truncate, aseptate, greenish to olivaceous, thin- and smooth-walled, without a gelatinous sheath or appendages.
Teleomorph: not known.

Description adapted from Tulloch (1972).