Entoloma peechiense 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 : 104-106

Entoloma peechiense K. N. A. Raj & Manim. , sp. nov. Figs. 2A–H

MycoBank MB 820065

Etymology:—The specific epithet refers to the type locality of this species.

Diagnosis:—Characterized by a conico-convex pileus with a slight central depression and a recurved-squamulose surface, versiform cheilocystidia with fine encrustations, a trichoderm-type pileipellis, basidiospores measuring 11–19 × 8–13 μm, and distinctive ITS (KY643746) and nLSU (KY643725) sequences. Differing from Entoloma sepiaceobasale in having a conical, conico-convex or convex pileus with yellowish brown or brown recurved squamules all over, a relatively shorter, brownish orange or light brown stipe with appressed- to slightly recurved-squamules all over, and larger and versiform cheilocystidia.

Holotype:— INDIA. Kerala State: Thrissur District, Peechi Forest : 1 November 2011, K. N. Anil Raj AR924 (K(M) 191751).

Description:— Basidiocarps small, mycenoid. Pileus 4–13 mm diam., up to 8 mm high, somewhat conical or conico-convex to convex with or without a very shallow central depression; surface yellowish brown (5F5, 5F6, 5F7/ OAC735) or brown (6 E6, 6 E7/OAC721) at the center and on the squamules and grayish orange (6B3/OAC633) or brownish orange (5C3/OAC745) or dark yellowish brown (5D4/OAC743) elsewhere, not hygrophanous, not striate, recurved-squamulose all over, densely so at the center; margin initially incurved and crenulate, becoming almost deflexed and wavy with age. Lamellae sinuate or emarginate, close, initially pinkish white (7A2/OAC549), becoming grayish red (7B3/OAC556) or brownish orange (7C3, 7C4/OAC612) with age, up to 4 mm wide, with lamellulae in 2–3 tiers; edge finely torn or crenulate to somewhat fimbriate, concolorous with the sides. Stipe 13–41 × 1–4 mm, central, terete, equal or slightly tapering towards the apex, hollow; surface brownish orange (5C3, 6C3/OAC613) or grayish brown (5D3/OAC745) or light brown (6D4/OAC721), appressed- to slightly recurved-squamulose all over; base with scanty mycelium. Odor and taste not distinctive.

Basidiospores 11–19 × 8–13 (13.7±1.50 × 9.8±1.16) μm, Q = 1.1–1.7, Qm = 1.40, nodulose-multiangled, heterodiametric-ovate, 5–7-angled, rarely 8-angled, pale yellow or pale brownish yellow, thick-walled. Basidia 32– 51 × 9–21 μm, clavate, pale yellow, thin- to slightly thick-walled, 4-spored; sterigmata up to 6 μm long; mature basidia project slightly beyond the hymenial surface. Abortive basidia and collapsed basidia occasionally present in the hymenium. Lamella-edge sterile or rarely heterogeneous. Cheilocystidia crowded, 18–142 × 10–27 μm, versiform: clavate, fusiform, broadly fusiform, narrowly lageniform, conical or cylindrical with an obtuse apex, with a pale-yellow wall pigment and fine brown internal encrustations, thin- to slightly thick-walled. Pleurocystidia none. Lamellar trama subregular; hyphae 3–11 μm wide, with a yellowish brown wall pigment and dark brown external encrustations, thinto slightly thick-walled. Subhymenium inconspicuous or distinct. Pileus trama subregular; hyphae 3–17 μm wide, with a yellowish brown wall pigment and fine dark brown external encrustations, thin- to slightly thick-walled. Pileipellis a trichoderm; hyphae 7–26 μm wide, with a brownish yellow wall pigment and dark brown external encrustations, thin- to slightly thick-walled; terminal cells 33–112 × 8–26 μm, cylindrical or tapering with an obtuse apex, with an internal uneven wall devoid of encrustations. Stipitipellis a disrupted cutis or a trichoderm made up of loose, ascending hairs; hyphae 4–15 μm wide, with a pale yellow or pale brownish yellow wall pigment and dark brown external encrustations, thin- to slightly thick-walled; terminal cells 33–103 × 8–16 μm, cylindrical or tapering with an obtuse apex. 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: Thrissur District, Peechi Forest , 18 August 2011, K. N. Anil Raj, AR810 (K(M) 191752) ; 16 September 2011, K. N. Anil Raj, AR879 (K(M) 191754).

Comments:—The brownish pileus and stipe with squamulose surfaces, the nodulose-angular basidiospores and the dark brown external encrustations on all hyphae indicate that E. peechiense belongs to the section Dysthales . Entoloma sepiaceobasale (E. Horak 1983: 26) Blanco-Dios (2015: 37) , an Argentinean species ( Horak 1983), shares some features with E. silvanum in having an almost similar-sized (10 mm) pileus with a somewhat similar golden brown color, emarginate lamellae with a fimbriate edge, almost similar-sized (15–19 × 7.5–9 μm) basidiospores, the presence of cheilocystidia, a trichoderm-type pileipellis composed of thick-walled, brown externally encrusted hyphae and a stipitipellis with slightly thick-walled, pale brown externally encrusted hyphae. However, E. sepiaceobasale has a convex to plane pileus with a faint orange tint and a velutinous to hairy, striate-sulcate margin; ventricose, pale gray-brown lamellae; a longer (60 mm), woolly-hairy stipe which is golden brown at the upper half and blue-black at the lower half and smaller (22–45 × 12–25 μm) clavate to vesiculose cheilocystidia. Entoloma pulvereum Rea in Smith & Rea (1907: 170), a species known only from Great Britain and the Netherlands ( Noordeloos 1992), shows some similarity to E. peechiense in having a conico-convex pileus with erect squamules all over, cheilocystidia with encrusted walls, and a disrupted cutis-type stipitipellis with externally encrusted hyphae. However, E. pulvereum differs from E. peechiense in having larger basidiocarps with a red-brown or yellow-brown pileus, dark grayish pink lamellae that are adnate or emarginate with a small decurrent tooth and showing both transvenose and intervenose nature, a stipe with a squamulose upper half and a fibrillose-striate lower half, smaller basidiospores (10.0–12.5(–13.0) x 7.0–8.0(–9.0) μm), a sterile lamella-edge with smaller cheilocystidia (20–70 x 7–20 μm), a pileipellis which is a transition between a cutis and a trichoderm, and a stipitipellis with larger terminal elements (45–125 x 10–25 μm).

Entoloma farinosum (Largent & Skye Moore in Largent et al. 2011: 455) Noordeloos & G.M. Gates (2012: 347) from Australia ( Largent et al. 2011; Noordeloos & Gates 2012) has somewhat similar-sized basidiocarps, squamulose pileus and stipe surfaces and basidiospores of somewhat similar size and shape. However, that species differs in the color and shape of the pileus, the attachment of the lamellae and the shape and size of the cheilocystidia and in having pileocystidia.

The ITS and the nLSU sequences derived from Entoloma peechiense were proved to be distinct in a megablast search. In the megablast search of the GenBank nucleotide database using the ITS sequence of E. peechiense , no close hit was observed with an e-value of zero. Entoloma nodosporum (GenBank AF261308) with 90% sequence identity was the closest hit using nLSU sequence. Entoloma nodosporum (G.F. Atkinson 1902: 114) Noordeloos (1979: 215) shows no macro-morphological and microscopic similarities with E. peechiense . The pairwise comparison of the ITS sequences of Entoloma peechiense with those of the other three species described in this paper showed no significant similarity with an e-value of zero. The nLSU sequence of E. peechiense showed 88% similarity with those of both E. silvanum and E. tropicum . The nLSU sequence of E. peechiense showed no similarity with that of E. wayanadense with an e-value of zero.

Figures

FIGURE 2. A–H: Entoloma peechiense (K(M) 191751, holotype). A. Basidiomata; B. Basidiospores; C. Basidium; D–F. Cheilocystidia; G. Pileipellis; H. Stipitipellis. Scale bars: A= 10 mm; B–F = 10 μm; G–H= 100 μm. Photos by K. N. Anil Raj.