Chaetorostrum quincemilensis, gen. et sp. nov., a new freshwater ascomycete and its Taeniolella-like anamorph from Peru

Abstract

Collections of woody debris from streams in a lower montaine cloud forest in Peru yielded a novel fungus with affinities to the family Annulatascaceae. Characters which place it in the family Annulatascaceae sensu lato include ascomata which are brown pigmented; long periphysate necks; long tapering septate paraphyses; unitunicate, pedicellate asci with a prominent bipartite Japical ring; and ascospores with a gelatinous sheath. Examination of morphological characters provided a diagnosis which did not fit with existing genera and species in this family. The combination of features that distinguish this fungus are a pigmented ascoma with a neck which is hyaline at the apex and has prominent black hairs, fasciculate asci with a spine-like pedicellar extension, and versicolored ascospores which are constricted at the midseptum. The fungus also produces its anamorphic state in culture which is the first record of an asexual state in the Annulatascaceae. The new genus Chaetorostrum is erected to accommodate this undescribed fungus. The type species of Chaetorostrum, C. quincemilensis is described, illustrated and compared with other morphologically similar taxa in the family.