Tropicoporus oceanianus A.H. Zhu, Yuan Yuan & S.H. He, 2024

Zhu, An-Hong, Liu, Zhan-Bo, Li, Yue, Liu, Hong-Gao, Yuan, Yuan & He, Shuang-Hui, 2024, Molecular and morphological data reveal two new species of Tropicoporus (Hymenochaetaceae, Basidiomycota) from Australia and tropical Asia, MycoKeys 103, pp. 57-70 : 57

Tropicoporus oceanianus A.H. Zhu, Yuan Yuan & S.H. He sp. nov.

Figs 2 , 3

Type.

Australia. Queensland, Cains, Whitfield Conservation Park , on living tree of Eucalyptus , 18.V.2018, Dai 18859 (holotype, BJFC027327, isotype will be sent to MEL) .

Etymology.

Oceanianus (Lat.): refers to the species being found in Oceania.

Description.

Basidiomata. Perennial, pileate, solitary, woody hard and without odor or taste when fresh, bone hard when dry; pilei ungulate to triquetrous, projecting up to 2 cm, 3 cm wide, and 2.5 cm thick at base; pileal surface vinaceous gray to black when fresh and dry, concentrically sulcate with narrow zones, velutinate to glabrous, encrusted with age, distinctly cracked; margin more or less acute, snuff brown. Pore surface fawn brown when fresh, becoming umber when dry, glancing; sterile margin fawn brown when fresh and dry, distinctly paler than pores, up to 2 mm wide; pores circular, 6-7 per mm; dissepiments thick, entire. Context homogeneous, fulvous, woody hard, up to 3 mm thick, a black crust present at pileal surface. Tubes concolorous with pore surface, bone hard to brittle, up to 22 mm long, annual layers indistinct.

Hyphal structure. Hyphal system trimitic in context, dimitic in trama; generative hyphae simple septate; all hyphae IKI-, CB-; tissue becoming blackish brown in KOH.

Context. Generative hyphae infrequent, pale yellowish, thin- to thick-walled, rarely branched, frequently septate, 2-3 µm in diam; skeletal hyphae dominant, yellowish to brown, thick-walled with a narrow to medium lumen, dichotomously branched like the so-called skeleto-binding hyphae, strongly flexuous, interwoven, skeletal parts 3-5 µm in diam.

Trama of the tubes. Generative hyphae hyaline to pale yellowish, thin- to thick-walled, rarely branched, frequently septate, 2-2.5 µm in diam; skeletal hyphae thick-walled with a medium lumen, rarely branched, aseptate, flexuous, loosely interwoven, 2.5-3 µm in diam; hymenial setae occasionally present, subulate, dark brown, 22-30 × 4.5-6.5 µm; cystidioles present, fusoid, hyaline, thin-walled, 10-18 × 3.5-5 µm; basidia barrel-shaped, with four sterigmata and a simple septum at the base, 9-12 × 4-5 µm; basidioles capitate, slightly smaller than basidia.

Spores. Basidiospores broadly ellipsoid to subglobose, thick-walled, mostly collapsed, IKI-, CB-, (5-)5.2-6(-6.1) × (3.8-)4-5(5.1) μm, L = 5.60 μm, W = 4.61 μm, Q = 1.21 (n = 30/1).

Figures

Figure 2. Basidiomata of Tropicoporus oceanianus (Dai 18859, holotype).

Figure 3. Microscopic structures of Tropicoporus oceanianus (drawn from the holotype Dai 18859) a basidiospores b basidia and basidioles c cystidioles d hymenial setae e hyphae from context f hyphae from trama. Scale bars: 5 µm (a); 10 µm (b-f).