New species and records of saprophytic ascomycetes (Myxotrichaceae) from decaying logs in the boreal forest

Decayed wood from fallen white spruce (Picea glauca) and trembling aspen (Populus tremuloides) collected in northeastern Alberta, Canada, was the source of new isolates of species in the ascomycete genera Gymnostellatospora and Pseudogymnoascus. In addition to new reports of G. japonica, G. frigida and P. roseus, two new species are described. Gymnostellatospora canadensis sp. nov. resembles G.japonica but differs in producing brown ascomata and in the formation of an arthroconidial anamorph. Gymnostellatospora subnuda sp. nov. is distinct in lacking differentiated peridial hyphae. Gymnostellatospora alpina was not found in decayed wood but is reviewed based on extralimital material. A dichotomous key to the five species of Gymnostellatospora is provided.