肉眼的特徴: 傘は径 7-13 mm, 釣り鐘形で平開せず, しばしば周縁部に浅い溝線を表し,

やや吸水性, 乾性, 初め白色粉状, のち平滑になり, 全体に類白色, 時に中央部が淡褐色を帯

びる.　肉は傘の中央部において厚さ 0.3 mm 以下, 白色, 特別な味や臭いはない. 柄は 15-20

×1-1.3 mm, 円柱形, 中心生, やせ型, 中空, 乾性, 上部は白色粉状, 下部は長毛に被われ,

頂部は類白色～灰紫色, それ以外の部分は淡紫色を帯び, 根本は白色の剛毛に被われる. ヒ

ダは上生し, 疎 (柄に到達するヒダは 13-16), 幅 1.7 mm以下, 類白色, 縁取りを欠く.

顕微鏡的特徴: 担子胞子は 8-9.5×4-5 μm, 楕円形, 表面は平坦, 無色, アミロイド, 薄壁.

担子器は 24-31×6.5-7.5 μm, こん棒形, 4胞子性. 縁シスチジアは 17-28×11-20 μm, 群

生し, 広こん棒形, 不規則に配列した複数の円柱形～短指状分岐物 (2-18×1-3 μm)に被わ

れ, 無色, 薄壁. 側シスチジアを欠く. 子実層托実質の菌糸は偽アミロイド. 傘の上表皮層の菌

糸は匍匐性で, 幅 3-5μm, 平行に配列し, 円柱形, しばしば複数に分岐した疣状～短指状突

起に被われ, 無色, 薄壁. 上表皮下層の菌糸は無色, 実質の大部分は偽柔組織状

[pseudoparenchymatous: 著しく肥大し, 複数の隔壁を持った短形の菌糸細胞] で, 菌糸は平

列 し，偽アミロイド. 柄表皮は多分枝菌糸からなり, 無色または淡紫色. 傘の表皮及び実質の

菌糸にクランプが存在する.

供試標本: KPM-NC0008731 (holotype), Izumino-mori, Yamato-shi, Kanagawa pref., 16

Nov. 1999, coll. H.Takahashi; the same place, 25 Nov. 1999 coll. H. Takahashi; the same

place, 27 Nov. 1999, coll. H.Takahashi.

コメント: 傘は類白色、柄は淡紫色を帯び下部を中心に長毛に被われ, 縁シスチジアは

広こん棒形でまばらに配列した円柱形～短指状の分岐物に被われ, 側シスチジアを欠き,

傘と柄の表皮組織は多分枝菌糸が存在し, 菌糸はクランプを持つ. 晩秋の頃 (11月),

シラカシ, コナラを中心とする広葉樹林内の落ち枝上に発生.

本種は Maasの分類概念 (Maas 1985) によるクヌギタケ節 (section Mycena) に属し, 節内

において本種は類白色の傘, 縁シスチジアの類型, 材上生の生態においてマレーシア産

Mycena obcalyx Corner (Corner 1994) と共通した性質を示すが, マレーシア産種はより小型

の子実体を形成し, ヒダがやや垂生し, 柄は透明白色で全体に粉状を帯び, 担子胞子が広楕

円形になる点で異なる.

Mycena multiplicata Har. Takah., Mycoscience (2007) 48: 342-357.

Etymology: From Latin, multiplicata = multiplicative.

Pileus 7-13 mm in diam, conico-convex to campanulate, often shallowly sulcate-striate

toward the margin, dry, subhygrophanous, minutely white pruinose at first, soon becoming

glabrous, almost whitish overall from the outset, sometimes pale brownish at the center.

Flesh up to 0.3 mm, white; odor and taste not distinctive. Stipe 15-20×1-1.3 mm,

cylindrical, central, slender, terete, hollow, dry, white pruinose above, pilose toward the base,

whitish to greyish violet (17C3) at the apex, dark violet (17F4-5) downward; base covered

with long, fairly coarse, whitish fibrils. Lamellae adnexed, distant (13-16 reach the stipe), up

to 1.7 mm broad, thin, whitish; edges concolorous.

Basidiospores (n = 63 spores of 6 basidiocarps) 8-9.5×4-5 μm, Q (length/breadth) = 1.

9-2, ellipsoid, smooth, colorless, amyloid, thin-walled. Basidia 24-31×6.5-7.5 μm, clavate,

four-spored, with clamps at the basal septa. Basidioles clavate. Cheilocystidia 17-28×11-

20 μm, abundant, forming a sterile lamella edge, obpyriform to broadly clavate, covered

with a few to numerous, unevenly spaced, simple to somewhat branched, cylindrical, straight

or curved to flexuous excrescences 2-18×1-3 μm, colorless, thin-walled. Pleurocystidia

absent. Hymenophoral trama regular; element hyphae 7-20 μm wide, cylindrical, often

inflated, walls thin, smooth, hyaline, dextrinoid. Pileipellis a cutis of parallel, repent hyphae 3-

5 μm wide, cylindrical, covered with simple to much branched diverticulae, walls thin,

colorless; underlying hyphae parallel, hyaline, dextrinoid, with short and inflated cells up to 52

μm wide. Stipitipellis a cutis of parallel, repent hyphae 2-10 μm wide, cylindrical,

diverticulate, colorless or pale violet, dextrinoid, thin-walled; caulocystidia 2-6 μm wide,

cylindrical, distinctly diverticulate, colorless, thin-walled. Stipe trama composed of

longitudinally running, cylindrical hyphae 5-13 μm wide, smooth, hyaline, dextrinoid. Clamp

connections present in the pileipellis, the pileitrama, and at the basal septa of basidia.

Known distribution: Japan (Kanagawa).

　 Habitat: Solitary or scattered, on dead fallen twigs in lowland forests dominated by

Quercus myrsinaefolia Blume and Q. serrata Thunb.ex Murray.

Specimens examined: KPM-NC0008731 (holotype), Izumino-mori, Yamato-shi, Kanagawa

pref., 16 Nov. 1999, coll. H.Takahashi; the same place, 25 Nov. 1999 coll. H. Takahashi; the

same place, 27 Nov. 1999, coll. H.Takahashi.

Japanese name: Keashi-ochiedatake.

　 Notes: This species is distinct in its whitish pileus, the dark violet, pilose stipe, the

amyloid basidiospores, the obpyriform to broadly clavate cheilocystidia covered with a few

to numerous, unevenly spaced, cylindrical excrescences, the lack of pleurocystidia, and the

diverticulate elements in the cortical layer of pileus and stipe. These characteristics suggest

placement of this taxon in the section Mycena, as defined by Maas Geesteranus (Maas

Geesteranus 1985). Within the section, Mycena multiplicata is comparable with M. obcalyx

Corner from Malaya (Corner 1994) in having a grayish white pileus, lobulate cheilocystidia

with digitiform processes, and lignicolous habitat. The latter species, however, differs in

forming much smaller basidiomata (pileus 2-4 mm wide: Corner 1994) with subdecurrent

lamellae and a entirely pruinose, hyaline white stipe, and broadly ellipsoid basidiospores.