Entoloma wayanadense K. N. A. Raj & Manim., 2017

Anil Raj, K. N. & Manimohan, Patinjareveettil, 2017, Four new species of Entoloma subgenus Pouzarella from India, Phytotaxa 307 (2), pp. 101-112 : 102-104

Entoloma wayanadense K. N. A. Raj & Manim. , sp. nov. Figs. 1A–F

MycoBank MB 820064

Etymology:—The specific epithet refers to the Wayanad District of Kerala State where this species was first observed.

Diagnosis:—Characterized by a greyish brown pileus beset with long (up to 10 mm), recurved hairs; emarginate to almost decurrent lamellae; a stipe covered with long, loose hairs; absence of both cheilo- and pleurocystidia, basidiospores measuring (12–)14–17 × 8–11.5 μm, and distinctive ITS (KY643748) and nLSU (KY643723) sequences. Differing from Entoloma strigosissimum in having a fertile lamella-edge, a tropical location, and a distinctive ITS sequence.

Holotype:— INDIA. Kerala State: Wayanad District, Tirunelli Forest , 16 November 2010, K. N. Anil Raj, AR522 (K(M) 191742).

Description:— Basidiocarps small, mycenoid. Pileus 7–14 mm diam., somewhat convex or conico-convex with or without a small central umbo; surface grayish brown (7E3/OAC627) or brown (7E4/OAC626) at the center and grayish orange (5B3/OAC759) or pale orange-gray (5B2/OAC760) elsewhere, not hygrophanous, not pellucid-striate, with long (up to 10 mm), recurved hairs all over; margin initially incurved and crenate, becoming almost straight and finely wavy with age. Lamellae emarginate with a small decurrent tooth or almost decurrent, close, brownish gray (7C2/ OAC506) or brownish orange (7C3/OAC611), up to 4 mm wide, with lamellulae in 2–3 tiers; edge entire, concolorous with faces. Stipe 22–38 × 1–2.5 mm, central, terete, equal, hollow; orange-gray (6B2/OAC669) or brownish gray (6E2/ OAC724) or brown (6 E4, 6 E5/OAC638), covered with long, loose hairs all over; base with a small amount of basal mycelium. Odor and taste not distinctive.

Basidiospores (12–)14–17 × 8–11.5 (15.61±1.02 × 9.57±0.86) μm, Q = 1.3–1.8, Qm = 1.63, rather nodulose-multiangled, heterodiametric-ovate, with 7–8 concave or flat facets, pale brownish yellow, thick-walled. Basidia 25– 49 × 12–18 μm, clavate, pale yellow, thin- to slightly thick-walled, 4-spored; sterigmata up to 5 μm long. Lamella-edge fertile. Cheilocystidia and pleurocystidia none. Lamellar trama subregular; hyphae 5–9 μm wide, with a brownish yellow wall pigment and dark brown external encrustations, thin- to slightly thick-walled. Subhymenium narrow. Pileus trama subregular; hyphae 4–14 μm wide, with a pale brownish yellow wall pigment and dark brown external spiral encrustations, thin- to slightly thick-walled. Pileipellis a cutis disrupted by trichodermal patches; appressed hyphae 10.5–24 μm wide, with a pale yellowish brown wall pigment and dark brown external encrustations, thin- to slightly thick-walled; hyphae of trichodermal patches composed of short inflated basal cells and narrow or setiform terminal elements; basal cells 35–40 × 17.5–22.5 μm, thick-walled, with brown external encrusting pigment; terminal cells narrow or setiform, with a dark brown intraparietal pigment, without external encrustations, thick-walled, widely septate. Stipitipellis a trichoderm, made up of loose long, entangled hyphae; hyphae 4–8 μm wide, with a pale brownish yellow wall pigment and fine, dark brown external encrustations, thick-walled; terminal cells 19–115 × 8–11 μm, cylindrical with a tapering or obtuse apex, with a yellowish brown wall pigment and fine, dark brown external encrustations, thick-walled. Caulocystidia absent. Clamp connections not observed on any hyphae.

Habitat:—scattered or in small groups, on the forest floor, among decaying leaf litter, under broadleaf trees.

Geographical distribution range:—known only from the type locality in Kerala State, India.

Additional specimens examined:— INDIA. Kerala State: Wayanad District, Tirunelli Forest, 27 November 2009, K. N. Anil Raj, AR135 (K(M) 191743).

Comments:—The grayish brown pileus with a hairy surface, the hairy stipe, the nodulose-angular basidiospores and the dark brown external encrustations on all hyphae of E. wayanadense are hallmarks of the section Dysthales of the subg. Pouzarella . Entoloma strigosissimum ( Rea 1920: 325) Noordeloos (1979: 211) a species found in North America ( Mazzer 1976) and Europe ( Noordeloos 1992), resembles the present species in having a conico-convex pileus, the same densely hairy surface features of the pileus and stipe, a similar size and shape to the basidiospores and the same cellular structure of the pileipellis. However, E. strigosissimum differs from E. wayanadense in having a sterile lamella-edge with cheilocystidia and also it occurs in temperate regions. A pairwise comparison of the ITS sequence of E. wayanadense with that of E. strigosissimum (JF908004) showed no similarity with an e-value of zero. No nLSU sequences of E. strigosissimum are available for comparison. Entoloma horridum (E. Horak 1980: 38) Noordel. & Co-David in Co-David et al. (2009: 169) from Papua New Guinea is somewhat similar to E. wayanadense in having long strigose hairs on the pileus, emarginate lamellae and lamella-edges lacking cheilocystidia. However, E. horridum differs from E. wayanadense in having dark brown basidiomata, a plano-convex or subdepressed pileus and smaller-sized (11–14 × 6–8 μm) basidiospores ( Horak 1980). The ITS and the nLSU sequences of E. horridum are not available for comparison.

The ITS (419 bp) and the nLSU (560 bp) sequences of E. wayanadense seem to be distinct. Megablast searches of the GenBank nucleotide database using these sequences did not result in any significantly close hits. A pairwise comparison of the ITS sequences of E. wayanadense with those of the other three species described in this paper showed no similarity with an e-value of zero. The pairwise comparison of the nLSU sequences of E. wayanadense and E. tropicum showed 89% similarity with an e-value of zero. However, the nLSU sequence of E. wayanadense showed no similarity to the nLSU sequences of the other two species, i.e., E. peechiense and E. silvanum with an e-value of zero.

Figures

FIGURE 1. A–F: Entoloma wayanadense (K(M) 191742, holotype). A–B. Basidiomata; C. Basidiospores; D. Basidium; E. Pileipellis; F. Stipitipellis. Scale bars: A–B = 10 mm; C–D= 10 μm; E–F= 100 μm. Photos by K. N. Anil Raj.