Auriscalpium flabellatum sp. nov. (Auriscalpiaceae), a species from Japan producing basidiomata directly from soil

A new species, Auriscalpium flabellatum (Auriscalpiaceae), is described from Japan. While A. orientale, which typically grows on conifer cones, is the only known species of Auriscalpium in Japan, A. flabellatum produces basidiomata directly from soil. The basidiocarps are small, laterally stipitate, and have fan-shaped pilei with fimbriate margins. Morphological examination revealed distinctive features, including amyloid basidiospores that are subglobose to broadly elliptic, and a dimitic hyphal system with gloeocystidia. Molecular phylogenetic analyses based on the internal transcribed spacer (ITS) region of rDNA placed this species within the Auriscalpium–Gloiodon clade. Clear morphological and ecological differences from known species support the recognition of A. flabellatum as a new species based on substrate specificity, pileus morphology, and phylogenetic evidence.