Plagiostoma populinum  

Anamorph: Discosporium populeum. Conidiomata 700-800 µm, eustromatic, immersed, subperidermal, flattened-globose, convoluted, uni- or multilocular, with a thick brown wall. Conidiophores hyaline, short, branched mostly from the base. Conidiogenous cells ± cylindrical, proliferating percurrently, with very well-developed periclinal thickening, collarette minute. Conidia 9-11 x 7-8 µm, obovoid, greyish brown in mass, thick-walled, aseptate, smooth, the base truncate.

Teleomorph: Ascomata 500-600 µm diam, necks just emergent. Peridium composed of an outer layer of thick-walled brown cells and an inner layer of compressed, hyaline, thin-walled cells, with a periphysate neck. Asci 70-85 x 12-15 µm. Ascospores 16-23 x 6-9 µm, tardily septate, slightly constricted at the septum, without appendages.

Description contributed by Graham Kinsey (CABI), and adapted from Sutton (1980). The species is also known as Cryptodiaporthe populea, and was considered as a synonym of the GB & I species Plagiostoma salicellum by Sogonov et al. (2008).