Hohenbuehelia tristis G. Stev.

Khalid, Muhammdah, Razzaq, Fauzia, Ashraf, Urooj, Afshaan, Najam-ul-Sehar & Khalid, Abdul Nasir, 2024, Three new records of genus Hohenbuehelia (Pleurotaceae, Agaricales) in Pakistan, Italian Botanist 18, pp. 179-191 : 179-191

Hohenbuehelia tristis G. Stev. , Kew Bull. 19 (1): 26 (1964)

Fig. 5

Description.

Basidiomata small-sized, solitary to gregarious, overlap on fallen small branches, soft. Pileus 0.8–1 cm in width, 0.4–0.7 cm in length, dimidiate to flabelliform, spathulate, petaloid when immature, light grey (10 YR 8 / 1-2) to whitish towards margins, shiny, slightly translucent, surface sparsely pubescent, margins incurved. Lamellae decurrent, radiating from the attachment point, white to creamy white, broad, sub-distant, lamellulae present in 1–4 tiers. Stipe absent, sometimes dorsally attached pseudo-stipe present, 0.3 cm long when young, disappear at maturity. Odour and Taste not recorded.

Basidiospores (6.07 –) 6.20–7.60 (– 7.70) × (4.10 –) 4.15–4.50 (– 4.55) µm, avl × avw = 7.0–4.40 µm, Q = 1.40–1.80 µm, Qav = 1.58 µm, sub-ellipsoid to oblong, smooth, thin-walled, guttulate, inamyloid, hyaline in 5 % KOH. Basidia (20.0 –) 22.30–26.90 (– 22.66) µm, avl × avw = 24.40 × 6.90 µm, narrowly clavate to sub-cylindrical, mostly with 4 sterigmata, some with 2 sterigmata, 2–3.5 µm long, smooth, thin-walled, basidioles numerously present, hyaline in 5 % KOH. Cheilocystidia (15.50 –) 15.80–16.90 (– 17.45) × (6.15 –) 6.30–6.95 (– 7.05) µm, avl × avw = 16.40 × 6.68 µm, lecythiform, mucronate, sub – lageniform, with capitate apex, thin to slightly thick-walled, hyaline in 5 % KOH. Pleurocystidia (34.80 –) 36.10–79.85 (– 82.05) × (9.0 –) 9.65–17.95 (– 19.60) µm, avl × avw = 59.90 × 13.63 µm, metuloid, fusiform, conical, narrowly utriform, encrusted with crystals towards base, extremely thick – walled with narrow lumen, very abundant, brownish in 5 % KOH. Hymenophoral trama – sub – regular, hyphae 2.60–4.70 µm in diam., thin-walled, septate, clamp – connections present, hyaline. Pileipellis ixotrichoderm, with cylindrical terminal elements, with brown intracellular pigments, pileocystidia absent, pileus trama composed of two types of hyphae; 1) horizontally arranged thin hyphae, 1.85–2.30 µm wide, septate, thin-walled, clamped, hyaline, 2) interwoven hyphae, 3.10–4.70 µm wide, septate, smooth, slightly thick-walled, hyaline, clamp – connections frequently present.

Habit and habitat.

Gregarious to imbricate, on small dead fallen branches.

Specimen examined.

Pakistan, Islamabad, Margalla Hills National Park, Trail 5 , 33°40'43"N, 72°52'32"E, at 1580 m a. s. l, 27 August, 2023, Fauzia Razzaq, Fatima Rehmat, (AN- 203: GenBank no. PP 702161, LAH 38210 ) .

Figures

Figure 5. Micro-morphological features of Hohenbuehelia tristis (AN- 203): A, B basidiomata on fallen branch C basidiospores D cheilocystidia (cap pointed by the arrow) E basidia (sterigmata pointed by the arrow) F hymenophoral hyphae G pleurocystidia H pileipellis hyphae with clamped-connections and terminal elements (arrow pointed). Scale bars: 0.5 cm (A, B); 5 µm (C); 10 µm (D); 10 µm (E); 5 µm (F); 10 µm (G); 5 µm (H).