A revision of Sphaeria pilosa Pers. and re-evaluation of the Trichosphaeriales

Sphaeria pilosa, the basionym of the type of Trichosphaeria, T. pilosa, was insufficiently described by Persoon. The current interpretation of T. pilosa comes from Fuckel and is based on his own material published in the exsiccatal series Fungi Rhen. Exs. no. 946. The examination of the type and other authentic material of S. pilosa and T. pilosa revealed several different fungi. Fresh material of T. pilosa is not available and Fuckel's historical specimens have never been sampled for DNA. In order to reconcile Persoon's concept of S. pilosa with Fuckel's concept of T. pilosa, we designate a neotype in our study. The species is a unitunicate ascomycete characterized by perithecial ascomata, persistent paraphyses, and cylindrical short-stipitate asci without visible apical annulus containing eight hyaline, ellipsoidal ascospores. The genus Trichosphaeria includes 87 described species and the Trichosphaeriales with the single family Trichosphaeriaceae recently accommodate 17 genera of apparently diverse phylogenetic affinity. Although the relationship of Trichosphaeria with other members of the Sordariomycetes is unknown, the family and order based on it are widely used to label incertae sedis clades inferred in phylogenetic analyses. Based on these findings, the Trichosphaeriales are re-evaluated and their use in phylogenetic studies is recommended to be abandoned until recognition of T. pilosa by molecular data.