Lentinus velutinus Fr., Linnaea 5: 510 (1830)

Facesoffungi number: FoF 3144                                                                              

Pileus 2–10 cm diam., thin, coriaceous, deeply umbilicate to broadly infundibuliform or cyathiform; surface uniformly pale greyish-cinnamon to rufous or tawny brown, fuscous at the centre, at times almost chestnut brown, dry, uniformly velutinate to short hispid or subsquamulose-furfuraceous, not zonate or obscurely so, neither strongly striate nor sulcate except in very old specimens; margin thin, at first strongly involute, reflexed at maturity, densely ciliate, at times fissile and fenestrated. Lamellae arcuate, short decurrent, not anastomosing, pale buff to cinereous brown, fulvescent, often tinted dark violaceous brown, narrow, 1–1.5 mm wide, moderately to densely crowded, with lamellulae of 3–4 lengths; edge entire. Stipe central, eccentric or lateral, slender, 2–25 cm × 2–10 mm, cylindric, expanding slightly at both apex and base, solid; surface concolorous with the pileus or more often darker, uniformly and persistently velutinate with the indumentums extending into the bases of lamellae, generally arising from a pseudosclerotium. Pseudosclerotium 2–10 × 1–4 cm, rarely larger, irregularly fusoid, comprising sclerified wood impregnated with hyphae, surface pale greyish-brown, smooth. Context thin, up to 1 mm thick, white, drying rigid, consisting of a dimitic hyphal system with generative hyphae.

Generative hyphae 2–4 μm diam., narrow, not inflated, hyaline, thin-walled, rather sparingly branched, with clamp connections. Skeletal hyphae, 2–4 μm diam., cylindric, hyaline, with a thickened wall of 1–2 μm and a narrow, continuous lumen, unbranched, arising in either an intercalary or terminal position, and then with an obtusely rounded apex. Basidiospore print pale buff to cream colour. Basidiospores 5–7 × 3–4 μm, Q =1.87, short, oblong-cylindric, hyaline, thin-walled, with few contents. Basidia 18–22 × 4–5 μm, narrowly cylindric, bearing 4 sterigmata. Lamella-edge sterile, with numerous basidioles and scattered sclerocystidia. Basidioles 16–30 × 4–8 μm, sinuous clavate or fusoid, constricted, often nodulose, hyaline, thin-walled. Sclerocystidia present on lamella-edge and more especially on sides of lamellae, fairly numerous to very abundant, 20–64 × 3–12 μm, initially clavate and thin-walled with refractive gloeo-contents, soon developing a thickened wall of 2–2.5 μm, hyaline or brownish, not or scarcely projecting beyond the basidia. Hymenophoral trama irregular, of radiate construction, hyaline, similar in structure to the context. Subhymenial layer little developed, 5–12 μm wide, interwoven. Pileipellis a trichodermal palisade producing erect, loose fascicles, 30–1000 μm long, of brown, thick walled, generative hyphae, 3–6 μm diam., with clamp connections, and an obtusely rounded apex, arising from a gelatinized hypodermium of radially repent generative hyphae. Stipitipellis similar to the pileipellis. No special smell; edible when it is young.

Habit, habitat and distribution: solitary, usually on dead or decaying wood, May to August. Our collection was collected on a decaying wood near Peradeniya Royal Botanic Gardens.

Specimens examined: SRI LANKA, Kandy District, near Peradeniya Royal Botanic Gardens, 11 June 2012, Samantha C. Karunarathna (MFLU 12-1123). GenBank number ITS:KY649465.

Notes: the wide distribution of Lentinus velutinus complex has resulted in a range of variations and in some instances constant morphological differences limited to restricted geographical areas. This is the first report of L. velutinus with the molecular phylogenetic confirmation from Sri Lanka after Pegler (1983) has previously reported it.

Phylogenetic relationships inferred from maximum parsimony analysis of ITS-rDNA sequences of 36 taxa. The percentages of replicate trees in which the associated taxa clustered together in the bootstrap test (1,000 replicates) are shown next to the branches. The tree is drawn to scale, with branch lengths in the same units as those of the evolutionary distances used to infer the phylogenetic tree. The new Sri Lankan records: Lentinus sajor-caju, having GenBank number KY649463 and herbarium number MFLU 12-1478; Lentinus squarrosulus, having GenBank number KY649464 and herbarium number MFLU 12-1228; Lentinus velutinus, having GenBank number KY649465 and herbarium number MFLU 12-1123 are shown in bold and blue. The topology is rooted with Panus lecomtei. Evolutionary analysis was conducted in PAUP 4.0b 10.

 

Basidiocarps of Lentinus velutinus in the field (MFLU 12-1123)

 

Lentinus velutinus (MFLU 12-1123) a Basidia. b Basidiospores. c Cheilocystidia. d Sclerocystidia. e Generative hyphae & Skeletal hyphae. f Hairs on pileus Scale bars: a, c, d = 20 µm, b, f, e = 10 µm