Tylopilus glutinosus, a new species of Boletaceae from Bangladesh

Abstract

Tylopilus glutinosus sp. nov. is described and illustrated from Bangladesh based on morphology and molecular data. This species is characterized by its caespitose habit, a purple pileus that becomes very viscid when wet, unchanging context, an ixotrichodermial pileipellis with the outer layer consisting of 3–4 cylindrical cells and the inner layer composed of filamentous hyphae, broadly fusoid to fusoid basidiospores and putative association with Shorea robusta. Morphologically, this species resembles T. plumbeoviolaceoides and T. plumbeoviolaceus. However, some distinctive macro‐ and microscopic features along with geographical distribution and host preference can be used to separate them from each other. Furthermore, analysis of DNA sequences of the nuclear ribosomal large subunit (nrLSU) undoubtedly placed them in different lineages or clades within Tylopilus. Detailed morphological descriptions, illustrations, a phylogenetic reconstruction and comparison with related taxa of Tylopilus are also provided.