シロチャヒラタケ

Crepidotus virgineus Har.Takah., Mycoscience (2003) 44:103-107　

国内産類似菌

1. コナカブリ(欧州産Crepidotus cf. variabilis)の胞子は楕円形～長楕円形で微細な突起に被われ、広こん棒形または珊瑚状の縁シスチジアを形成。

2. ニセコナカブリ(欧州産Crepidotus cf. cesatii)の胞子は類球形で微細な突起に被われ、縁シスチジアはこん棒形で不規則な分岐物を持つ。

3. コナカブリモドキ (欧州産 Crepidotus cf. epibryus = Pleurotellus hypnophilus)は平滑な胞子を持つ点でシロチャヒラタケと共通しますが、欧州産epibryusは胞子紋の色が薄く、ヒダはほぼ白色～部分的に淡紅色を帯び、胞子は長楕円形、縁シスチジアは円柱形の付属糸を持ちます。

上記の類似菌の顕鏡データは欧州産種に基づきます。日本産近縁種群については再検討が必要です。

欧州産チャヒラタケ属の主なモノグラフ

1. Consiglio, G. et al. (2008) Il Genere Crepidotus in Europa. A.M.B. 344p

2. Nordstein, S. (1990) The Genus Crepidotus (Basidiomycotina, Agaricales) in Norway. Synopsis fungorum2. 115p 3.

3. B. Senn-Irlet (1995) The genus Crepidotus (Fr.) Staude in Europe | Semantic Scholar

肉眼的特徴: 子実体は微小 (径 4-13 mm), 軟質, 無柄または退化した短い柄を持ち, 側生,

時に背着生, 腎臓形～半円形. 傘の表面は細軟毛状 (pubescent)～繊維状, 全体に白色, 老

成すると汚白色になる; 縁部は最初内側に巻く. 肉は厚さ 0.5 mm 以下, 白色, 特別な味や臭い

はない. ヒダはやや疎 (基部に到達するヒダは 12-16), 幅 1.5 mm 以下, 最初白色, のちピン

ク色, 成熟時帯褐色, 縁部は同色.

顕微鏡的特徴: 胞子は 6.5-7.5×3.5-4.5μm, 楕円形, 平坦, 蜜色, 厚壁. 担子器は 6.5-7.5

×3.5-4.5μm, こん棒形, ４胞子性. 縁シスチジアは 30-55×5-13μm, 群生し, 類こん棒形～

脚部の長い類紡錘形または不規則な円柱形, 無色, 薄壁. 側シスチジアはない. 傘表皮の菌糸

は平行菌糸被を形成し, 幅 4-13μm, 錯綜し, 円柱形, しばしば不規則な形状になり, 無色, 薄

壁. 全ての組織の菌糸はクランプを持つ.

供試標本: KPM- NC0008717 (基準標本), Izumino-mori, Yamato-shi, Kanagawa-ken, May

19, 2001, coll. H.Takahashi; KPM- NC0008718, the same place, May 23, 2001, coll. H.

Takahashi; Mt.Takao, Hachiouji-shi, Tokyo, Japan, July 7, 1999, coll. H.Takahashi; the same

place, June 23, 2000, coll. H.Takahashi.

コメント: チャヒラタケ節 (Section Crepidotus) に属し, 白色, ヒラタケ型の子実体を形成し,

平滑, 楕円形の胞子を有し, 菌糸にクランプを持つ. 林内の落枝上に発生し, 関東地方では普

通に見られる. 標本は神奈川県立生命の星・地球博物館の標本庫(KPM)に登録, 収蔵されて

いる.

Crepidotus virgineus Har.Takah., Mycoscience (2003) 44:103-107　　

Basidiomata 4-13 mm in diameter, soft, sessile or with a short stipe, lateral or sometimes

dorsal, reniform to semiorbicular. Pileus pubescent to fibrillose, white overall, sordid white in

age; margin at first incurved then straight. Flesh up to 0.5 mm thick, white; odor and taste

not distinctive. Lamellae subdistant (12-16 reach the base), with 1-3 series of lamellulae, up

to 1.5 mm broad, at first white, then pinkish, finally becoming brownish; edges concolorous.

Basidiospores 6.5-7.5×3.5-4.5μm [Q = length/breadth: 1.6-1.8, n = 20 spores per two

specimens], ellipsoid, smooth, melleous in water, thick-walled. Basidia 14-23×5-7 μm,

clavate, four-spored. Cheilocystidia 30-55×5-13 μm, forming a compact sterile edge,

subclavate to subfusiform-pedicellate or irregularly cylindrical, colorless, thin-walled.

Pleurocystidia none. Hymenophoral trama subregular; hyphae similar to those of the

pileitrama. Pileipellis composed of interwoven, repent hyphae 4-13μm wide, cylindrical,

occasionally irregularly shaped, colorless, thin-walled. Hyphae of pileitrama 5-23 μm wide,

subparallel to irregularly arranged, cylindrical, sometimes irregularly inflated, colorless, thin-

walled. All tissues with clamp connections.

Known distribution: Japan (Honshu).

Habitat: Solitary to scattered, on fallen dead twigs in lowland oak forests, from May to

July, common.

Specimens examined: KPM- NC0008717 (holotype), Izumino-mori, Yamato-shi, Kanagawa-

ken, May 19, 2001, coll. H.Takahashi; KPM- NC0008718, the same place, May 23, 2001, coll.

H.Takahashi; Mt.Takao, Hachiouji-shi, Tokyo, Japan, July 7, 1999, coll. H.Takahashi; the same

place, June 23, 2000, coll. H.Takahashi.

Japanese name: Shiro-chahiratake.

Notes: This species is characterized by its pure white, reniform basidiomata, the smooth,

melleous, ellipsoid basidiospores, the subfusiform-pedicellate or irregularly cylindrical

cheilocystidia, and the presence of abundant clamp connections. Its smooth basidiospores

suggest the placement of this taxon in the section Crepidotus of the genus Crepidotus as

defined by Singer (1986).

Within the section, this species is most similar to neotropical Crepidotus antillarum (Pat.

apud Duss) Singer (Singer 1973), which differs in having much larger basidiospores (7.2-10.2

×4.5-6.8 μm) and broadly ventricose or vesiculose-clavate cheilocystidia. Crepidotus

virgineus is also comparable with Crepidotus epibryus (Fr.: Fr.) Quel. from Europe (Nordstein

1990; Senn-Irlet 1995) and Mexico (Moreno 1999) and North American Crepidotus

coloradenss Hesler & A.H.Sm. (Hesler and Smith 1965) in white basidiomata and smooth

basidiospores. These species differs in lacking clamp connections. Furthermore C. epibryus

has much narrower, amygdaliform basidiospores and narrowly lageniform, often branched

cheilocystidia, and C. coloradensis has flexuous, subulate cheilocystidia.