チャオニイグチ

Strobilomyces brunneolepidotus Har. Takah. & Taneyama, in Takahashi, Taneyama, Kobayashi, Oba, E. Hadano, A. Hadano, Kurogi & Wada, The fungal flora in southwestern Japan, Agarics and boletes 1: 155 (2016)

茶色の色素を持つ亜熱帯産オニイグチ属の仲間です。

主な形態的特徴: 傘は赤褐色の直立した刺状鱗片に被われ, 消失性の縁片膜を有する; 肉は空気に触れると赤褐色に変わる; 柄は痩せ型で, 頂部に縦長の網目状隆起を表し, 赤褐色の綿毛に密に被われる; 担子胞子は球形～類球形, 完全な網目状隆起を表す; 縁シスチジアこん棒形～広こん棒形または紡錘形; 側シスチジアは頂部が嘴状に伸びた片膨れ状.

コメント: 最も特徴的な本種の形質は傘と柄の表面を被う赤褐色の刺状鱗片および綿毛である. 中国南西部産Strobilomyces velutinus J.Z. Ying (Ying and Ma 1985) は赤褐色の鱗片に被われた傘を持つ点で本種に類似するが, 傘の鱗片はチャオニイグチの刺状鱗片と異なり, 平らに圧着する. また中国産種の網目状隆起を欠く平坦な柄, 黒変性のある肉, そしてイボ～刺状突起に被われたより大型の担子胞子: 10.1–12.6 × 8.6–10.8 μm (Ying and Ma 1985) は チャオニイグチには見られない特徴である.

　生態および発生時期: スダジイ、オキナワウラジロガシを主体とする常緑広葉樹林内地上に孤生, 6月.

分布: 沖縄 (石垣島).

Habitat and phenology: Solitary on the ground in Castanopsis-Quercus forests, June.

Known distribution: Okinawa (Ishigaki Island).

Holotype: TNS-F-48210, on the ground in an evergreen broad-leaved forest dominated by Q. miyagii Koidz. and C. sieboldii (Makino) Hatus. ex T. Yamaz. et Mashiba.

Japanese name: Cha-oni-iguchi (named by H. Takahashi & Y. Taneyama).

Comments: The most distinct features of the present fungus are the reddish-brown spiny warts and flocci that cover the entire surfaces of the pileus and stipe. Strobilomyces velutinus J.Z. Ying from south-western China (Ying and Ma 1985; Gelardi et al. 2013) has a certain similarity to the new species largely due to possessing a chestnut brown covering on the pileus. The Chinese taxon, however, forms a pileus ornamented with flat, areolate, patchy scales, unlike the erect, conical, spiny warts of S. brunneolepidotus. In addition, a non-reticulate, smooth stipe, black discoloration of flesh, and significantly larger, echinulate to verrucose or subcrested basidiospores: 10.1–12.6 × 8.6–10.8 μm (Ying and Ma 1985) distinguish S. velutinus from the S. brunneolepidotus.

References 引用文献

Gelardi M, Vizzini A, Ercole E, Voyron S, Wu G, Liu XZ. 2013. Strobilomyces echinocephalus sp. nov. (Boletales) from south-western China, and a key to the genus Strobilomyces worldwide. Mycol Progr 12 (3): 575–588.

Ying JZ, Ma QM. 1985. New taxa and records of the genus Strobilomyces in China. Acta Mycol Sin 4 (2): 95–102.