Polyporus thailandensis, a new species of group Polyporellus in Polyporus (Polyporales, Agaricomycota) from Northeastern Thailand

Polyporus thailandensis is described and illustrated as a new species from Thailand based on morphological and phylogenetic investigations. This species is characterized by centrally stipitate basidiocarps with umber to sienna glabrous pileus having minute cilia along the margin, round to angular pores, a dimitic hyphal system with often inflating generative hyphae, and cylindrical to ellipsoid basidiospores measuring 7-10.5 × 3-4.5 μm. Phylogenetic analyses based on the combined large subunit (LSU) and internal transcribed spacer (ITS) regions showed that P. thailandensis and P. tricholoma are closely related, but they differ in color of the pore surface and size of the basidiospores.