Microporellus terrestris Decock, Czech Mycol.

4. Microporellus terrestris (Gibertoni & Ryvarden) Decock, Czech Mycol. 59(2): 161 (2007). Figs. 5 a-c; 9e Basidiomata pileate, laterally to eccentrically stipitate, circular, coriaceous, up to 1 cm high, up to 1 cm in diameter, up to 2 mm thick. Abhymenial surface radially striate, faintly zonate, up to 2 zones, infundibuliform at the center, dark reddish-brown, glabrous. Margin obtuse to sub-truncate. Stipe darkish-brown, up to 0.5 mm high, up to 0.3 mm in diam., rugose, glabrous to pubescent in some parts. Context fibrous, pale brown, up to 1 mm thick. Tubes concolorous, up to 2 mm deep. Hymenial surface poroid, grayish-brown to pale brown. Pores visible to the naked eye, irregular, 2–3 per mm. Dissepiments entire, glabrous, moderately thick. Hyphal system dimitic. Generative hyphae with unilateral clamps, hyaline, simple septate, thin-walled, with refringent content, 3–4 μm diam. Skeletal-binding hyphae aseptate, thick-walled to solid, hyaline to brownish, variably dextrinoid, 1–3 μm diam. Cystidia absent. Basidia not found. Basidiospores frequent to abundant, hyaline, cylindrical to navicular, thin-walled to slightly thick-walled, often with ferruginous content, (7–)7.1–10(–11.5) × 3–4(–4.4) μm, Lm × Wm = 8.4 × 3.5 μm; Q = 1.9–2.9(–3.6), Qm = 2.4, (n = 77/1). Material examined: Juquitiba, São Paulo Green Belt Biosphere Reserve, Zé da Paz, 3.X.2021, F. Pagin et al. FP 494 (SP 528825). Xylophagous on angiosperm wood, the species causes white rot. The species was found in Brazil (Gibertoni et al. 2004; Drechsler-Santos et al. 2007). Previously recorded from the Brazilian Atlantic Forest of the state of Rio Grande do Norte (Gibertoni et al. 2004); Caatinga, from the state of Bahia (Drechsler-Santos et al. 2007). This is the first record from the Southeast of Brazil. The type locality of Microporellus terrestris is BaÍa Formosa, Rio Grande do Norte, Brazil (Gibertoni et al. 2004, as Navisporus terrestris Gibertoni & Ryvarden). Microporellus terrestris can be recognized in the field by its circular, laterally to eccentrically stipitate, coriaceous basidiomata, black and rugose stipe, faintly zonated, reddish-brown abhymenial surface, cream to beige hymenial surface, as well as by the 2–3 pores per mm, which are visible to the naked eye. In addition, its dimitic hyphal system composed by clamped generative hyphae and of skeletal-binding hyphae plus the navicular to cylindrical, (7–)7.1–10(–11.5) × 3–4(–4.4) μm, basidiospores are diagnostic. With the exception of Microporellus ellipsosporus Decock & Ryvarden, all species in the genus differ from M. terrestris by their tiny pores, presence of cystidia, and globose to lacrimoid basidiospores (Motato-Vásquez & Gugliotta 2016). Microporellus ellipsosporus is the closest species to M. terrestris in morphology, but the first differs by its narrower basidiospores, 1.7–2.3 μm width, and presence of hymenial cystidia (Decock & Ryvarden 2007).