ハイイロイタチタケ (別名: ウメネズイタチタケ)

Psathyrella cineraria Har. Takah., Mycoscience 41: 15-23, 2000　

≡ Coprinopsis cineraria (Har. Takah.) Örstadius & E. Larss., in Örstadius, Ryberg & Larsson, Mycol. Progr. 14 (no. 25): 37 (2015) 

近年、分子系統解析に基づき、外観が全く異質なヒトヨタケ属 Coprinopsis に転属されています。

ハイイロイタチタケは、Kits van Waveren (1985)の分類概念によるPseudostropharia 節に属する欧州産 Psathyrella melanthina (Fr.) Kits van Wav.（＝Hypholoma agaves Maire，≡ Coprinopsis melanthina (Fr.) Örstadius & E.Larss. ）に近縁と考えられます。

  肉眼的特徴: 傘は径30-60 mm, 最初釣り鐘形～半球形, 成熟時饅頭形～平開し, 時に中

丘を具え, 時に周縁部に条線を表し, 吸水性, 湿時暗灰色, 乾くと周縁部から退色し, 中央部は

早落性の暗灰色綿屑状小鱗片に密に被われ, 周縁部に向かって綿屑繊維状をなし, 間もなく

平滑になる.　肉は薄く (3 mm以下), 傘の中央部において暗灰色, それ以外は白色, 特別な味

や匂いはない.　柄は40-70×5-10 mm, ほぼ上下同大, 中心生, やせ型, もろく, 中空, 淡灰色,

上部は粉状, 下半部は暗灰色の反り返った繊維状鱗片に被われるが間もなく脱落し, 平滑に

なる; ツバを欠く; 根本は発達した綿毛状菌糸体に被われる.　ヒダは上生, 密 (柄に到達するヒ

ダは44-50), 幅4-7 mm, 薄く, 最初白色のち褐色. 胞子紋は褐色.

  顕微鏡的特徴: 担子胞子は 6.5-8.5×4-5μm, 卵形～楕円形, 平坦, 蜜色, 薄壁～やや厚

壁, 発芽孔を欠く. 担子器は 24-30×4-10μm, こん棒形, ４胞子性. 側シスチジアはない. 縁シ

スチジアは 25-50×5-18 μm, 群生し, フラスコ形, 平坦, 無色, 薄壁. 子実層托実質は無色. 傘

の表皮は短細胞被をなし, 菌糸細胞は類球形～球形, 25-95×20-40μm, 暗灰色粒状の凝着

色素に薄く被われ, 薄壁. 傘の被膜は円柱形の菌糸細胞 (20-60×5-13μm) からなり, 薄壁,

暗灰色粒状の凝着色素に被われる. 全ての組織にクランプが見られる.

  供試標本: CBM-FB-24144 (基準標本), on decayed wood of Q. myrsinaefolia, Yamato-

shi, Kanagawa-ken, 11May 1998; CBM-FB-24142, on decayed wood of Q. myrsinaefolia,

Yamato-shi, Kanagawa-ken, 5 May 1994; KPM-NC0005005, on decayed wood of Q.

myrsinaefolia, Setagaya-ku, Tokyo, 3 Jul. 1995; CBM-FB-24143, on decayed wood of Q.

myrsinaefolia, Yamato-shi, Kanagawa-ken, 24 Apr.1996; KPM-NC0005006, on decayed wood

of Q. myrsinaefolia, Sakura-shi, Chiba-ken, 4 Oct. 1997.

  コメント: 傘および柄の表面が暗灰色の消失性被膜に被われ, 膜質のツバを欠き, 担子胞

子は発芽孔を持たず, 側シスチジアは存在しない. 主にシラカシ等の広葉樹の材から発生. 標

本は神奈川県立生命の星・地球博物館 (KPM) 並びに千葉県立中央博物館 (CBM) の標本庫

に登録, 収蔵されている.

参考文献

1) Dahncke, R. M., 1993. 1200 Pilze in Farbfotos. 1179pp. AT Verlag, Aarau.

2) 帆足美伸 2007. 平塚市博物館収蔵のナヨタケ属菌不明種“ウメネズイタチタケ” について.

  神奈川自然誌資料(28): 41-44 Mar. 2007.

3) Kits van Waveren, E., 1985. The Dutch, French and British species of Psathyrella.

  Persoonia Suppl., 2: 1-300.

4) Malencon, G. & R. Bertault, 1970. Flore des champignons superieurs du Maroc 1, pp.179-

  222. Institute Scientifique cherifien et de la Faculte des Sciences de Rabat, Rabat.

5) Moser, M. & Julich, W. 1996., Color Atlas of Basidiomycetes. ⅢAgaricales. Psathyrella 12.

  Guatav Fischer Verlag.

6) Neville, P., 2000. Illustrations en couleurs, Psathyrella melanthina. Bull. FAMM., 17: 44.

7) Tassi, G., 2000. Le genre Psathyrella . Especes rares ou interessantes Ⅱ . Bull. Soc. Myc.

  Fr., 116: 343-384.

Psathyrella cineraria Har. Takah., Mycoscience 41: 15-23, 2000　　　　　Figs. 10-14

  Pileo 30-60 mm lato, primo campanulato-semigloboso, dein convexo vel applanato, e

medio versus marginem radiatim striato, hygrophano, in statu humectato obscure cineraceo,

cum squamulis fibrillosis obscure cineraceis obtecto, mox glabro, ad marginem appendiculato;

odore saporeque nullo; stipite 40-70×5-10 mm, aequali, cavo, pallide cineraceo, superne

pruinoso, inferne squamulis fibrillosis-recurvatis obscure cineraceis detersibilibus obtecto,

mycelio basali albo, villoso; lamellis adnexis, confertis, brunneis; basidiosporis 6.5-8.5×4-5 μ

m, melleis, levibus, ovoideis vel ellipsoideis, poro germinationis omnino destitutis; basidiis

tetrasporis; cheilocystidiis utriformibus vel lageniformibus; pleurocystidiis nullis; hyphis

fibulatis.

  Holotypus: In ramulis delapsis Quercus myrsinaefoliae Blume, Yamato-shi, Kanagawa-ken,

Japonia, 11 May 1998, H.Takahashi (CBM-FB-24144).

  Etymology: from Latin, cineraria = ash-grey referring the color of pileus.

  Pileus 30-60 mm in diam, at first campanulate-hemispherical, convex to applanate at

maturity, sometimes obtusely umbonate, radially striate toward the margin, hygrophanous,

dark grey when moist, drying to paler from the margin, center covered by a detersile dense

coating of fibrillose, dark grey squamules of the veil, downy-fibrillose toward the slightly

appendiculate margin, soon glabrescent. Flesh thin (up to 3 mm), dark grey in the center of

the pileus, white elsewhere, odor and taste not distinctive. Stipe 40-70×5-10 mm, almost

equal, central, terete, slender, brittle, hollow, pale grey, pruinose above, lower portion

covered with detersile, dark grey, recurved fibrillose-squamules of the veil remnants, soon

glabrescent; annulus absent; base covered with white, villose mycelium. Lamellae adnexed,

crowded (44-50 reach the stipe), 4-7 mm broad, thin, at first white then brown; edges

fimbriate, concolorous.

  Spore print brown (6E6-6E7). Basidiospores 6.5-8.5×4-5μm, ovoid to ellipsoid, smooth,

melleous, thin-walled, without germ-pore. Basidia 24-30×4-10μm, clavate, four- spored.

Pleurocystidia absent. Cheilocystidia 25-50×5-18 μm, abundant, utriform to lageniform

with an obtusely rounded apex, smooth, colorless, thin-walled. Hymenophoral trama regular;

element cells 30-150×8-20 μm, ellipsoid to cylindric, smooth, colorless, thin-walled.

Pileipellis an epithelium of subglobose to ellipsoid elements 25-95×20-40 μm, somewhat

incrusted with granules of dark grey pigment, thin-walled. Veil structure of pileus composed

of cylindric elements 20-60×5-13 μm, walls thin, incrusted with dark grey pigment

granules. Pileitrama of subparallel, inflated hyphae; elements ellipsoid to cylindric, 50-160×16

-22 μm, smooth, colorless, thin-walled. Stipitipellis a cutis of parallel, repent hyphae 4-6.5

μm wide, somewhat incrusted with granules of dark grey pigment, thin-walled. Veil

structure of stipe composed of branched, cylindric hyphae 2.5-8 μm wide, with ventricose

to clavate, cystidioid terminal cells, 20-85×3.5-14 μm, walls thin, somewhat incrusted with

dark grey pigment granules. Hyphae of stipe trama 8-16 μm wide, cylindric, longitudinally

running, smooth, colorless, thin- walled. Clamps present in all tissues.

  Known distribution: Japan (Chiba, Kanagawa, Tokyo). Habitat: Solitary to caespitose, on

decayed wood of Quercus myrsinaefolia Blume, from April to October, not common.

  Holotype: CBM-FB-24144, on decayed wood of Q. myrsinaefolia, Yamato-shi, Kanagawa-

ken, 11 May 1998. Other specimens examined: CBM-FB- 24142, on decayed wood of Q.

myrsinaefolia, Yamato-shi, Kanagawa- ken, 5 May 1994; KPM-NC0005005, on decayed wood

of Q. myrsinaefolia, Setagaya-ku, Tokyo, 3 Jul. 1995; CBM-FB-24143, on decayed wood of

Q. myrsinaefolia, Yamato-shi, Kanagawa- ken, 24 Apr. 1996; KPM-NC0005006, on decayed

wood of Q. myrsinaefolia, Sakura-shi, Chiba-ken, 4 Oct. 1997.

  Japanese name: Haiiro-itachitake.

  Notes: Psathyrella cineraria is not common in the lowland forest of eastern Japan, where

it appears to be restricted in its growth on the decayed wood of Quercus myrsinaefolia, but

further field work is necessary to clarify this point.

  The brown spore print, the relatively shorter basidiospores (less than 10 μm long)

without a germ pore, the utriform to lageniform cheilocystidia, the absence of pleurocystidia,

and the colorless trama of the lamellae suggest that P. cineraria belongs to the section

Argillosporae Singer in the subgenus Mycophylla A.H.Smith in Singer's (1986) classification.

  Psathyrella cineraria differs from all previously described taxa of the section

Argillosporae in the following combination of features: the dark grey incrusting pigment, the

dark grey, detersile, fibrillose- squamulose outer veil that forms slightly appendiculate

marginal veils in the pileus, and the absence of distinct annulus. Within the subgenus

Mycophylla, Psathyrella candolleana (Fr.) Maire, the type species of the section

Candolleanae (Romagn.) Singer, and Psathyrella pseudogordonii  Kits van Wav. (Kits van

Waveren, 1985) from England seem to be similar to P. cineraria. The former two taxa,

however, differ in forming a white or ocherous veil, lacking pigment incrustation, and having

basidiospores with a distinct germ pore. Psathyrella uliginicola McKnight & A.H.Smith (Smith,

1972) from North America also has a greyish pileus at the young stages, but it differs in

having a white or whitish stipe, no pigment incrustation, significantly longer basidiospores (10-

12 μm long) with a distinct germ pore, and a habit under aspen.