Four New Species of Hemileccinum (Xerocomoideae, Boletaceae) from Southwestern China

The genus Hemileccinum belongs to the subfamily Xerocomoideae of the family Boletaceae. In this study, phylogenetic inferences of Hemileccinum based on sequences of a single-locus (ITS) and a multi-locus (nrLSU, tef1-α, rpb1, rpb2) were conducted. Four new species, namely H. abidum, H. brevisporum, H. ferrugineipes and H. parvum were delimited and proposed based on morphological and molecular evidence. Descriptions and line-drawings of them were presented, as well as their comparisons to allied taxa. Our study shed new light on the recognition of the genus. The pileipellis of the species in this genus should mostly be regarded as (sub)epithelium to hyphoepithelium, because the pileipellis of most studied species here is composed of short inflated cells in the inner layer (subpellis) and filamentous hyphae in outer layer (suprapellis). The basidiospores of the studied species, including the type species, H. impolitum, have a warty surface.