First report of Polyporus ciliatus in Japan, and taxonomic re-evaluation of synonymous species described from Japan

Abstract

Polyporus ciliatus (Polyporales, Basidiomycota) is reported as a new record to Japan with a new Japanese name (“Ezono-amisugi-take”) based on both morphological and phylogenetic analyses of specimens from Hokkaido. Phylogenetic analyses revealed that P. ciliatus collections from Japan, China and Denmark had identical nuclear large ribosomal subunit sequences and formed a distinct clade with P. longiporus. Examinations of cultural characters revealed that P. ciliatus produce subglobose to fusiform, rarely clavate chlamydospores. We also re-evaluated the holotype of P. saitoi collected from Japan. Polyporus saitoi has been treated as a synonym of P. ciliatus, but the holotype has corky context, a reddish-brown pileus surface when dry, and larger pores [(3-) 4-5 pores/mm] than P. ciliatus, and it is morphologically distinct from P. ciliatus. We conclude that the status of P. saitoi as a valid species is dubious name because the holotype lacks microscopic characters besides skeletal-binding hyphae which are insufficient for species identification.