Inosperma hainanense2021

Inosperma hainanense Y.G. Fan, L.S. Deng, W.J. Yu & N.K. Zeng, sp. nov.2021 

MycoBank: MB840528

Holotype: e. China, Hainan Province, Changjiang Li Autonomous County, Bawangling substation of Hainan Tropical Rainforest National Park, under Castanopsis dominated forest, at 19°7'12.43"N, 109°7'6.29"E, alt. 630 m, 2 September, 2020, N.K. Zeng, Zeng4937 (FHMU3166), GenBank accession number: ITS (MZ374070); LSU (MZ374761) and rpb2 (MZ388104)

Morphological description

Asexual morph: small to medium-sized. Pileus 25–53 mm diam., conical to convex at young age, becoming applanate to uplifted with age, with a broad to subacute umbo, margin initially decurved, straight to somewhat wavy when mature; surface dry, smooth when young, fibrillose-rimulose elsewhere, strongly rimose towards the margin with age; chocolate brown (5D8) to somewhat dark brown (5F7) around the disc, straw yellow (4A6) to yellowish brown (4B5) elsewhere, background pallid to cream white (4B1), becoming brown (5B4) to dark brown (5C6) with age; Lamellae rather crowded, adnexed, initially ivory white (5A1) to grayish white (5B2), becoming dirty yellowish (5B5) to brownish (5C7) when matured, completely brown (5D6) after drying, 2–3 mm in width, edge fimbriate, slightly serrate. Stipe 40–72 × 3–5 mm, central, nearly terete, equal with a slightly swollen apex, base somewhat swollen; nearly smooth and longitudinally striate all over the stipe; initially ivory (5A1) to yellowish white (5A2) at the upper half, yellowish to brownish (4B5) downwards, becoming uniformly yellowish brown (4B7) to brown (4C7) with age. Context solid, fleshy in pileus, white to grayish white (4B1), pale brown under the umbo (4B2), 1–2 mm thick at midradius, 4–5 mm thick under the umbo, fibrillose in stipe, pallid to yellowish (4A2) or brownish (4B2), striate, shiny. Odor indistinct or slightly acid.

Sexual morph: [180/9/9] 8–9(10.5) × 5–7 μm, Q = (1.18)1.28–1.64 (1.78), Qm =  1.43, mostly ellipsoid to ovoid, occasionally subphaseoliform, smooth, slightly thick-walled, brown to yellowish brown, apiculus small, indistinct, with a spherical to ellipsoid yellowish brown oil-droplet. Basidia 21–28 × 6–9 μm, clavate, often obtuse at apex, slightly tapered towards the base, thin-walled, 4-spored, sometimes 2-spored, sterigmata 4–6 μm in length, with spherical yellowish brown to golden yellow brown oily inclusions. Pleurocystidia absent. Lamella edge sterile. Cheilocystidia 34–55 × 15–25 μm, abundant and crowded, mostly obovoid to balloon-shaped, occasionally broadly clavate, rarely enlongate-clavate, thin- to slightly thick-walled (up to 1 μm thick); often rounded or slightly obtuse at apex, colorless to pale yellow, sometimes with golden yellow pigments. Hymenophoral trama 75–138 μm thick, sub-regular, hyaline to slightly yellow, composed of cylindric to inflated hyphae 20–33 μm wide, slightly constricted at septa. Pileipellis a cutis, hyphae 2.5–10 μm wide, thin-walled, pale yellow to yellowish brown, cylindrical, sometimes slightly encrusted. Pileal trama regular to subregular, hyphae 12–30 μm wide thin-walled, colorless. Stipitipellis a cutis, regularly arranged, walls yellowish to bright yellow. Oleiferous hyphae 2.5–10 μm wide, commonly scattered in pileus and stipe tramal tissues, straw yellow or bright golden yellow, smooth, often bent or diverticulate. Clamp connections observed in all tissues.

Cultures:

Habitat: Scattered or gregarious in small clusters under Castanopsis dominated forest, June to September in tropical China

Distribution: China (Hainan, Guangdong).

GenBank Accession: its  MZ374069; lsu  MZ374760; rpb2  MZ388103.  Its MZ374070;  lsu MZ374761 ; rpb2 MZ388104.its  MZ374071; lsu  MZ374762; rpb2  MZ388105.

Notes:

Reference: [1] Deng, L. ,  Kang, R. ,  Zeng, N. K. , &  Fan, Y. G. . (2021). Two new inosperma (inocybaceae) species with unexpected muscarine contents from tropical china. MycoKeys.

 Basidiomata of Inosperma hainanense a–e basidiomata f–g rimose to rimulose pileus h lamellae i lamellae edge j–k stipe surface. c FHMU3166 (holotype) a–b, d–g, i–k FHMU6511 h FHMU3168. Scale bars: 10 mm (a–k). a–b, d–k: photos by L.-S. Deng; c: photos by N.-K. Zeng