Basidiomata of Mycena mustea.  Bars A 1 mm; B 4 mm; C 7 mm; D 2 mm.

Mycena mustea. A Basidiospores. B Basidium and basidiole. 
  C Cheilocystidia. D Elements of the pileipellis. Bars 10 μm.

スミレアシナガタケ Mycena mustea Har. Takah., Mycoscience (2007) 48: 342-357. 
  肉眼的特徴: 傘は径 7-10 mm, 釣り鐘形で平開せず, しばしば中高の饅頭形になり, やや
吸水性, 湿時半透明の条線を表し, やや吸水性, 乾性, 初め白色粉状, のち平滑になり, 幼時
淡灰紫色のち次第に退色する. 肉は傘の中央部において厚さ 0.5 mm 以下, 白色, 特別な味
や臭いはない. 柄は 40-90×0.5-1.5 mm, 円柱形, 中心生, やせ型, 中空, 乾性, 最初白色粉
状, のち平滑になり, 全体に灰紫色を帯び, 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 15-19), 幅 1.2 mm以下, 淡褐色, 縁取りを欠く. 
  顕微鏡的特徴: 担子胞子は 11-12×6-7 μm, 短楕円形〜楕円形, 表面は平坦, 無色, 非ア
ミロイド〜弱アミロイド, 薄壁. 担子器は 28-37×8-10μm, こん棒形, 2-4胞子性. 縁シスチジア
は 30-45×8-11 μm, 群生し, こん棒形, 通常頂部に 1-3個の瘤状分岐物を具え, 無色, 薄
壁. 側シスチジアを欠く. 子実層托実質の菌糸は非アミロイド. 傘の上表皮層の菌糸は匍匐性
で, 幅 2-6μm, 平行に配列し, 円柱形, 疣状〜短指状突起に被われ, 無色, 薄壁. 上表皮下層
の菌糸は無色または淡紫色, 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. 柄表皮の菌糸
は平坦, 無色または淡紫色. 菌糸はクランプを欠く.
  供試標本: KPM-NC0008699 (holotype), Ikuta-ryokuchi, Kawasaki-shi, Kanagawa pref., 30 
Nov. 2000, coll. H.Takahashi; same place, 13 Nov. 1999, coll. H.Takahashi; same place, 23 Nov. 
2000, coll. H.Takahashi. 
  コメント: 傘と柄は灰紫で平滑になり, 担子胞子は非アミロイド〜弱アミロイド, 縁シスチジアは
こん棒形で通常頂部に 1-3個の分岐物を具え, 側シスチジアを欠き, 傘の表皮組織は多分枝
菌糸が存在し, 菌糸はクランプを欠く. 晩秋の頃 (11月), 神奈川県川崎市生田緑地のイヌシ
デ, シラカシを中心とする広葉樹林内の落枝上に発生. 標本は神奈川県立生命の星・地球博
物館 (KPM) の標本庫に登録, 収蔵されている.
  弱アミロイドの担子胞子を重視すれば, 本種は Maasの分類概念 (Maas 1980, 1988a) に
よるアクニオイタケ節 Sect. Fragilipedes に属すると思われる. しかしながら, ヒダ実質が非アミ
ロイドであること, また柄の表皮組織が多分枝菌糸を欠く性質を重視すれば, コウバイタケ節
Sect. Adonideae との類縁も考えられる.
  北米産 Mycena umbrinovinosa Maas G. (Maas 1985; Smith 1947)は本種に近縁と思われる
が, 北米産種は傘が紫褐色〜紫黒色で, 縁シスチジアは頂部に長形の分岐物を具え, 菌糸は
クランプを有する. 欧州産 Mycena urania (Fr.: Fr.) Quel. (Kuhner 1938; Lisiewska 1987; Maas 
1984; Moser and Julich 1999; Robich 2003; Smith 1947)も本種に似るが, 傘は紫黒色で, 縁シ
スチジアは等間隔に配列した微小疣が密生し, 菌糸はクランプを持つ.
Mycena mustea Har. Takah., Mycoscience (2007) 48: 342-357. 
  Etymology: From Latin, mustea = fresh. 
  Pileus 7-10 mm in diam, conico-convex to campanulate, occasionally with low and broad 
umbo, faintly translucent-striate when moist, subhygrophanous, dry, minutely white pruinose 
at first, soon glabrescent, evenly colored dull violet (16E3-4) when young, then somewhat 
paler near the margin. Flesh up to 0.5 mm, white; odor and taste not distinctive. Stipe 40-90
×0.5-1.5 mm, cylindrical, central, slender, terete, hollow, dry, dull violet (16E4) to grayish 
violet (16E5-6) over the entire length, at first entirely white pruinose, glabrescent in age; 
base white strigose. Lamellae adnexed, distant (15-19 reach the stipe), up to 1.2 mm broad, 
thin, pale brownish; edges pruinose, concolorous.
   Basidiospores (n = 83 spores of 10 basidiocarps) 11-12×6-7 μm, Q (length/breadth) = 
1.7-1.8, short ellipsoid to ellipsoid, smooth, colorless, inamyloid to weakly amyloid, thin-walled.
 Basidia 28-37×8-10 μm, clavate, mostly four-spored. Basidioles clavate. Cheilocystidia 
30-45×8-11 μm, abundant, forming a sterile lamella edge, clavate, apically with one or 
more short knob-like excrescences, colorless, thin-walled. Pleurocystidia not seen. 
Hymenophoral trama regular; element hyphae 5-16 μm wide, cylindrical, often somewhat 
inflated, walls thin, smooth, colorless, inamyloid. Pileipellis a cutis of parallel, repent hyphae 
2-6 μm wide, cylindrical, covered with scattered, warty or finger-like diverticulae, walls thin, 
hyaline; underlying hyphae parallel, hyaline or pale violet, dextrinoid, with short and inflated 
cells up to 25 μm wide. Stipitipellis a cutis of parallel, repent hyphae 2-6 μm wide, 
cylindrical, smooth, hyaline or pale violet, thin-walled. Stipe trama composed of 
longitudinally running, cylindrical hyphae 8-15 μm wide, smooth, colorless, dextrinoid. 
Clamp connections absent in all tissues.
  Known distribution: Japan (Kanagawa). 
    Habitat: Solitary to scattered on dead fallen twigs in lowland forests dominated by 
Carpinus tschonoskii Maxim. and Quercus myrsinaefolia Blume. 
  Specimens examined: KPM-NC0008699 (holotype), Ikuta-ryokuchi, Kawasaki-shi, 
Kanagawa pref., 30 Nov. 2000, coll. H.Takahashi; same place, 13 Nov. 1999, coll. H.Takahashi; 
same place, 23 Nov. 2000, coll. H.Takahashi. 
  Japanese name: Sumire-ashinagatake.
  Notes: This species is characterized by its glabrescent, dull violet to grayish violet pileus 
and stipe, the weakly amyloid basidiospores, the clavate cheilocystidia apically with one or 
more short knob-like excrescences, the absence of pleurocystidia, the diverticulate 
pileipellis elements, and the absence of clamp connections. 
  Its violet pigment, the inamyloid hymenophoral trama, and the smooth hyphae of the 
cortical layer of stipe suggest that this species belongs in the section  Adonideae  (Fr.) 
Quel., as defined by Maas Geesteranus (Maas Geesteranus 1980, 1990). However, if greater 
taxonomic emphasis is placed on the weakly amyloid basidiospores, it would be better placed 
in the section Fragilipedes (Fr.) Quel. (Maas Geesteranus 1980, 1988a).
     Mycena mustea seems to be closely allied with North American M. umbrinovinosa Maas 
Geest. (Smith 1947; Maas Geesteranus 1985) which differs in having a vinaceous brown to 
purplish black pileus, irregularly shaped cheilocystidia apically covered with long, flexuous 
excrescences, and clamp connections.  Mycena mustea is also similar to European M. urania
(Fr.: Fr.) Quel. (Kuhner 1938; Smith 1947; Maas Geesteranus 1984; Lisiewska 1987; Moser 
and Julich 1999; Robich 2003) which differs in forming a blackish violet pileus, broadly 
clavate cheilocystidia covered with numerous, evenly spaced warts, and clamp connections.
    Mycena mustea might be mistaken also for M. fonticola Har. Takah., but can be 
distinguished as follows. The pileus in M. mustea usually becomes pale greyish purple when 
mature; the cheilocystidia has several short digitate excrescences at the above portoin; the 
stipitipellis is made up of smooth elements. The pileus in M. fonticola becomes intensely 
violet brown when mature; the cheilocystidia has no excrescences; the elements of 
stipitipellis are covered with scattered, warty or finger-like diverticulae.