Amauroderma laccatostiptatum Gomes-Silva, Ryvarden & Gibertoni, 2015

Gomes-Silva, Allyne C., De Lima-Júnior, Nelson C., Malosso, Elaine, Ryvarden, Leif & Gibertoni, Tatiana B., 2015, Delimitation of taxa in Amauroderma (Ganodermataceae, Polyporales) based in morphology and molecular phylogeny of Brazilian specimens, Phytotaxa 227 (3), pp. 201-228 : 213-215

Amauroderma laccatostiptatum Gomes-Silva, Ryvarden & Gibertoni , sp. nov., Fig. 7

MycoBank: MB 811029

Amauroderma laccatostiptatum is characterized by the dark brown to black basidiomata, laccate stipe and globose, finally ornamented basidiospores. It is similar to A. picipes , which has globose to subglobose basidiospores [8–11 (–12) × 7–8 μm].

Holotype:— BRAZIL. Rondônia: Porto Velho, Estação Ecológica de Cuniã , on soil, February 2008, A.C. Gomes-Silva 390 ( URM 83238 , isotype O).

Etymology: —laccatus (Latin) = looking as if varnished, stipitatum (Latin) = stipitate, referring to the stipe.

Basidiomata annual, solitary, centrally to laterally stipitate. Pileus single, semicircular to circular, applanate to infundibiliform, 1.5–3.0 cm wide, 1–2.5 cm high, 0.2 mm thick, hard when dry. Stipe cylindrical, lateral to central, 5–12 cm long, 0.3–0.5 diam., slightly incurved, laccate, red to black (Blood red 41 to Fuscous black 36), context of the stipe with two black lines, fibrous, cream (B 2). Abhymenial surface dull, glabrous, concentrically zonate, slightly sulcate, brown to black (Cigar brown 16). Margin entire, acute, concolorous to the abhymenial surface, involute when dry. Hymenial surface cream to brown (B 2 to Buff 52), poroid, pores angular, 7–8 per mm, dissepiments entire, thin. Tubes concolorous to the hymenial surface, up to 0.1 mm deep. Context with two black lines that extend into the stipe, not seen in young specimens, slightly soft, 0.1–0.2 mm thick, cream (B 2). Hyphal system dimitic; generative hyphae hyaline, clamped, thin-walled, 1.5–2.5 μm in diam.; skeletal hyphae hyaline to yellow, thick-walled to solid, arboriform, 4–5 μm diam., IKI- to slightly IKI+. Hyphal pegs absent. Basidia not seen. Basidiospores globose to subglobose, hyaline to pale yellow in HOH, thick-walled, finely ornamented, usually guttulate, 8–10 × 7–8 μm, IKI-.

Substrate: —on soil.

Distribution: —only known from the States of Amazonas, Pará and Rondônia in the Brazilian Amazonia.

Specimens examined: — BRAZIL. Amazonas: Weir, 1923 (O). Pará: Melgaço, Estação Científica Ferrerira Penna, February 2008, T.B. Gibertoni et al. 260 (URM 80021), T.B. Gibertoni et al. 303 (URM 83246). Rondônia: Porto Velho, Floresta Nacional do Jamari, April 2013, A.C. Gomes-Silva 7 (HFSL), Parque Natural Municipal de Porto Velho, February 2008, A.C. Gomes-Silva 283 (URM 83237).

Remarks: —This new species is characterized by the dark brown to black basidiomata, laccate stipe and globose to subglobose, finally ornamented basidiospores. Until now, only two species of Amauroderma were known with entirely or partly laccate basidiomata: A. renidens , which has laccate pileus and stipe, and A. picipes (Bres.) Torrend (1920: 132) , with laccate stipe. Besides having laccate, reddish brown pileus, A. renidens has larger pores (3–4/mm), homogeneous context and distinctly ornamented basidiospores, while A. picipes has more robust basidiomata, larger pores (5–6/mm) and slightly larger basidiospores [9–11 × 7–8 μm] ( Ryvarden 2004 a, Gomes-Silva & Gibertoni 2012).

Figures

FIGURE 7. Amauroderma laccatostipitatum (URM 83238). A. Basidioma. B. Hymenial surface. C. Basidiospores in KOH. D. Basidiospores in SEM. Scale: A–B = 1 cm; C = 10 μm; D = 2 μm. Photos:A.C. Gomes-Silva.