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

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) x 4.1-5.1 mu m, 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 Paraiba 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.

Automated summary

Neotropicomus australis var. porulosus is a fungal species with small basidiomata, dark reddish brown pileus, greenish hymenophore with small pores, and brownish stipe. It is characterized by specific microscopic features including pale to slightly dark yellowish basidiospores, an epithelium pileipellis, phylloporoid tube trama, and caulocystidia with cylindrical projections. This species was discovered in the Caatinga biome of northeastern Brazil, marking the first record of this genus in the region. A modification of the genus to include small-pore specimens and a new combination of Xerocumus globuliger with Neotropicomus are also proposed.