りゅうきゅうきんもうわらび (琉球金毛蕨) [Index] [Back]

Hypodematium fordii

Hypodematium fordii

わが国の沖縄群島にある沖縄島北部、および中国南東部に分布しています。石灰岩地の切り立った崖の岩肌の窪みに生え、高さは5〜20センチになります。根茎は短く地面に這い、黄金色の鱗片を密につけます。葉は三角状長楕円形の3回羽状深裂です。胞子嚢群は辺縁と中肋の間につき、歪んだ円形で、包膜にはまばらに腺毛があります。環境省のレッドブックでは絶滅危惧IA類(CR)に分類されています。中国語では「福氏腫足蕨(fu shi zhong zu jue)」と呼ばれます。
イワテンダ科キンモウワラビ属の常緑シダ類で、学名は Hypodematium fordii (syn. Hypodematium ryukyuense)。英名はありません。
The "Ryukyu-kinmou-warabi" (Hypodematium fordii) belongs to the family Woodsiaceae. It is an evergreen fern that is found in the northern part of Okinawa Island in Japan's Okinawa Islands, as well as in southeastern China. It grows in crevices on the rock faces of steep cliffs in limestone areas and reaches a height of 5 to 20 cm. The rhizome is short and creeping along the ground, densely covered with golden-yellow scales. The leaves are triangular-lanceolate and deeply three-pinnately lobed. The sori are located between the margin and the midrib; they are oblong and irregularly shaped, with sparse glandular hairs on the indusium. The Ministry of the Environment's Red List classifies it as Critically Endangered (CR). In Chinese, it is called "福氏腫足蕨" (fu shi zhong zu jue).
茨城県つくば市「つくば実験植物園」にて、2026年03月28日撮影。

Shu Suehiro
shu@botanic.jp