A new genus and species of Phialocephala-like fungi with cordiform conidia in Chaetosphaeriaceae.

A Phialocephala-like hyphomycete was found on a dead petiole of the fern Angiopteris lygodiifolia in Taiwan. It differs from all other known fungi by its pale brown cordiform conidia in brown masses on the top of penicillately branched dematiaceous conidiophores, and is described as new genus and species Phaeophialocephala cardiospora. By its pigmented conidia, this species differs from Phialocephala trigonospora, which is transferred to another new genus, Cardiocephala, Sordariomycetidae, incertae sedis. Phylogenetic analyses of ITS, LSU and TEF sequences indicate particularly close relationship of Phaeophialocephala cardiospora to Caligospora and Caliciastrum in the Chaetosphaeriaceae. An almost identical environmental ITS2 sequence from the USA and a brief morphological characterization from a fungus-distribution database in Denmark indicate that the fungus is probably widespread but rarely encountered.