Mujinamo - Mujinamo

A perennial plant of the Droseraceae family (APG classification: Droseraceae). It is an aquatic carnivorous plant that floats on the surface of quiet swamps and ponds, and has no roots. The stem is 10-25 cm long, somewhat branched, and has short internodes. The leaves grow in whorls of 6-8 at the nodes, with wedge-shaped stalks and several bristly projections at the top. The leaf blade opens and closes like a clam, and when a small insect enters it closes and digests it. In winter, the leaves hibernate in a dense sphere at the end of the branches. In July and August, a short stalk emerges from the leaf axil, and a single pale green flower blooms above the water surface. There are five sepals and petals. There are five stamens. There is one pistil with five styles, the end of which is finely split. The flower wilts in a day, and after flowering, the stalk sinks into the water and produces an oval, black fruit. Distributed in various places around the world, it grows rarely in parts of the Kanto region in Japan, and the one in Hozoji-numa, Hanyu City, Saitama Prefecture, is a national natural monument. The name comes from the fact that the whole plant resembles a badger's tail.

[Junko Kobayashi December 11, 2020]

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

モウセンゴケ科（APG分類：モウセンゴケ科）の多年草。静かな沼池の水面に浮かぶ水生食虫植物で、根はない。茎は長さ10～25センチメートル、多少分枝し、節間は短い。葉は節に6～8枚輪生し、柄はくさび形、上端に数個の剛毛状突起がある。葉身はハマグリ状に開閉し、小虫が入ると閉じて消化する。冬季は枝先に葉を球状に密集して越年する。7～8月、葉腋(ようえき)から短い柄を出し、水面上に淡緑色花を1個開く。萼片(がくへん)、花弁はともに5枚。雄しべは5本。雌しべは1本で5本の花柱があり、その先は細かく裂ける。花は1日でしぼみ、花期後、柄が水中に潜り、卵円形で黒色の果実を結ぶ。世界に点々と分布し、日本では関東地方の一部にまれに生育し、埼玉県羽生(はにゅう)市宝蔵寺沼のものは国の天然記念物である。名は、全草を狢(むじな)の尾に例えたもの。

［小林純子　2020年12月11日］

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