たにいぬわらび (谷犬蕨) [Index] [Back] わが国の本州、東北地方南部から四国・九州、南西諸島、それに台湾や朝鮮半島、中国、ヒマラヤ中西部に分布しています。山地のやや湿った林内に生え、高さは２０〜６０センチになります。葉は卵状長楕円形の２回羽状複葉で、緑色から鮮緑色のやや厚い草質です。葉柄や中軸、羽軸は紅紫色をしています。葉柄の基部には、黒色の鱗片を密につけます。羽軸と小羽軸の分岐点表面には、棘状の突起があります。胞子嚢群は中肋に接してつき、包膜は長楕円形で鉤形が混ざります。別名では「ひろばのいぬわらび（広葉の犬蕨）」。台湾華語では「光蹄蓋蕨」、中国語では「光蹄蓋蕨（guang ti gai jue）」と呼ばれます。 イワデンダ科メシダ属の常緑シダ類で、学名は Athyrium otophorum。英名は Eared lady fern。 The Eared lady fern (Athyrium otophorum) belongs to the family Woodsiaceae. It is an evergreen fern that is distributed from the southern part of the Tohoku region on Honshu to Shikoku and Kyushu, the Nansei Islands in Japan, as well as Taiwan, the Korean Peninsula, China, and the central-western Himalayas. It grows in slightly moist forests in mountainous areas and reaches a height of 20 to 60 cm. The leaves are ovate-lanceolate, twice-pinnately compound, and are green to bright green in color with a somewhat thick, herbaceous texture. The petioles, midribs, and pinnae are reddish-purple. The base of the petiole is densely covered with black scales. The surface of the junction between the rachis and the pinnae features spiny projections. The sori are attached to the midrib, and the indusia are oblong with some hoo-shaped variations. It is also known as "Hiroba-no-inu-warabi". In Taiwanese Chinese, it is called "光蹄蓋蕨", and in Chinese, it is known as "光蹄蓋蕨" (guang ti gai jue). 長崎県雲仙市小浜町「原生沼」にて、2026年05月12日撮影。 Shu Suehiro shu@botanic.jp