The genus Arachnomyces

Abstract

The genus Arachnomyces is redescribed and placed in the family Onygenaceae. Four species are described and illustrated. A. nitidus Massee & Salmon, the type of the genus, was collected on a hay-dung compost in Ontario and compared with the type specimen. The type of A. sulphureus Massee & Salmon was examined. A. peruvianus is a new combination for Anixiopsis peruviana Cain. A. minimus is a new species isolated in pure culture from decayed wood collected in Ontario. The peridium of the cleistothecial ascocarps of Arachnomyces consists of an outer dark layer and an inner hyaline layer and has long appendages (except in A. peruvianus). The asci are globose to subglobose and irregularly disposed. The ascospores are one-celled, oblate, reddish brown, smooth or roughened, without germ pores.