Amauroderma floriformum 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 : 212-213

Amauroderma floriformum Gomes-Silva, Ryvarden & Gibertoni , sp. nov., Fig. 6

MycoBank: MB 811028

Amauroderma floriformum is similar to A. partitum , differing from it by its deeply lobed pileus, resembling a small flower, the small, angular pores, and globose basidiopores.

Holotype:— BRAZIL. Rondônia: Porto Velho, Parque Natural Municipal de Porto Velho , on soil, January 2010, A.C. Gomes-Silva et al. 965 ( URM 83250 ).

Etymology: —flos (Latin) = flower; forma (Latin) = shape, referring to the shape of flower of the basidiomata. Basidioma annual, solitary or in clusters, lateraly stipitate. Pileus single or 2–9 lobed, semi-circular, applanate, 0.2–0.6 cm wide, 0.3–0.5 cm long and 0.1 mm thick, fragile when dry. Stipe cylindrical, lateral, solid, ramified at the apex, originating solitary or lobed pilei, 3.5–6.5 cm long, 0.1–0.2 mm diam., black (Fuscous black 36), dull, glabrous to slightly velutinate, with thin cuticle, context homogeneous, fibrous, brown (Snuff brown 17). Abhymenial surface dull, glabrous to slightly velutinate, slightly zonate and sulcate, reddish brown (Bay 19) when dry. Margin entire, acute, slightly involute when dry, concolorous to the abhymenial surface. Hymenial surface brown (Snuff brown 17), poroid, pores angular 5–6(7–) per mm, invisible to the naked eye, dissepiments entire, thin. Context homogeneous, fibrous, thin, approximately 0.05 mm thick, yellow to brown (H, Snuff brown 17). Tubes concolorous to the hymenial surface, approximately 0.05 mm deep. Hyphal system dimitic; generative hyphae hyaline, clamped, thin-walled, 2–3.5 μm diam.; skeletal hyphae hyaline to brown, thick-walled, arboriform, 3–4 μm diam., IKI- to IKI+. Hyphal pegs absent. Basidia not observed. Basidiospores globose to subglobose, hyaline to yellowish in KOH, thick-walled, finally ornamented, usually guttulate, 9–10 × 8–9.5 μm, IKI-.

Substrate: —on soil.

Distribution: —only known from the State of Pará in the Brazilian Amazonia.

Specimens examined: — BRAZIL. Pará: Melgaço, Estação Científica Ferreira Penna, March 2007, T.B. Gibertoni 102, 151 (URM 79335, URM 80019); Cachoeira Porteira, INPA, June 1980, V.L. Bononi s.n (SP 193882, as A. omphalodes ), August 1980, V.L. Bononi 729 [SP 193391, as A. chaperi (Pat.) Murrill (1905a: 367) ]; Oriximiná, June 1980, V.L. Bononi 606 (SP 193620, como A. omphalodes ).

Remarks: — Amauroderma floriformum is characterised by its small basidiomata, deeply lobed pileus, dark reddish, dull abhymenial surface, angular pores and globose to subglobose, small basidiospores. Morphologically, it is similar to A. partitum (Berk.) Wakef. (1934: 242) , which has larges pores (1–3 per mm) and ellipsoid to oblong basidiospores [10–13 × 7–9.5(–10) μm].

Figures

FIGURE 6. Amauroderma floriformum (URM 83250) A. Basidioma. B. Basidiospores in Melzer’s reagent. C, D. Basidiospores in KOH. Scale: A = 1 cm; B–D = 10 μm. Photos: T.B. Gibertoni.