Hebelomina (Agaricales) revisited and abandoned

Abstract

Background and aims – The genus Hebelomina was established in 1935 by Maire to accommodate the new species Hebelomina domardiana, a white-spored mushroom resembling a pale Hebeloma in all aspects other than its spores. Since that time a further five species have been ascribed to the genus and one similar species within the genus Hebeloma. In total, we have studied seventeen collections that have been assigned to these seven species of Hebelomina. We provide a synopsis of the available knowledge on Hebelomina species and Hebelomina-like collections and their taxonomic placement.Methods – Hebelomina-like collections and type collections of Hebelomina species were examined morphologically and molecularly. Ribosomal RNA sequence data were used to clarify the taxonomic placement of species and collections.Key results – Hebelomina is shown to be polyphyletic and members belong to four different genera (Gymnopilus, Hebeloma, Tubaria and incertae sedis), all members of different families and clades. All but one of the species are pigment-deviant forms of normally brown-spored taxa. The type of the genus had been transferred to Hebeloma, and Vesterholt and co-workers proposed that Hebelomina be given status as a subsection of Hebeloma. In the meantime, Hebelomina-like Hebeloma, belonging to seven different species in three different sections, have been found. We conclude that Hebelomina should be abandoned as a supraspecific taxon.