Neotropicomus australis var. porulosus var. nov. (Agaricomycetes, Boletaceae), a new bolete from “brejo de altitude” forest in Brazil

Abstract Neotropicomus australis var. porulosus is characterized macroscopically by the small basidiomata, the dark reddish brown, slightly viscid and scrobiculate pileus with unchanging context, the greenish and unchanging hymenophore with small (≤0.5 mm in diam.) pores and the brownish stipe with unchanging context, creamy towards the base and fibrillose. Microscopically, the variety is characterized by pale to slightly dark yellowish basidiospores of 11.7–13.3(–13.8) × 4.1–5.1 µm, a pileipellis as epithelium consisting of erect to suberect then sometimes very slightly intertwined chains of aggregated globose, subglobose to ellipsoid cells, a phylloporoid tube trama, subparallel to barely divergent, and some caulocystidia with apex bearing an elongate cylindrical projection. The new taxon is described here from the Caatinga biome, in a ‘brejo de altitude’ forest in the states of Paraíba and Pernambuco. Thus, this is the first record of this genus from northeastern Brazil. We also propose here a modification of the genus to include small-pore specimens, and a new combination of Xerocumus globuliger with Neotropicomus.