Circumscription of species of Hodophilus (Clavariaceae, Agaricales) in North America with naphthalene odours

Five North American Hodophilus species with naphthalene-like odours are now recognized based on sequence and (or) morphological data and molecular annotation of type collections. Two well-supported eastern North American species do not match any of the studied types and are described here as new: Hodophilus hesleri and Hodophilus smithii. The previously described Hodophilus paupertinus is found to represent an autonomous species and appears restricted to western North America. Hodophilus subfuscescens is found to be an independent lineage in eastern North America. A morphological type study of Hodophilus peckianus shows that it is a distinct species and not represented among recent collections. Multilocus phylogenetic analyses of European and North American material of species with naphthalene odours reveal no species with transatlantic distributions. Overall, Hodophilus comprises two superclades (the Hodophilus foetens superclade and the Hodophilus micaceus superclade) and 16 terminal clades that correspond to phylogenetic species. This study introduces a new approach for morphological delimitation of agaricoid Clavariaceae combining shape and dimensions of particular elements in the pileipellis and caulocystidia. All previously described taxa included in this study, which were previously treated in the genera Hygrophorus, Camarophyllopsis, or Hygrotrama, are formally transferred to Hodophilus.