Ruri Tateha (Blue Admiral)

This butterfly belongs to the order Lepidoptera, family Nymphalidae. In Japan, it is found widely from Hokkaido to the Yaeyama Islands, but it is not a particularly common butterfly. Outside of Japan, it is found in the Korean Peninsula, China, Taiwan to India, and also in the mountainous areas of the Malay Archipelago, such as Sumatra, Java, Borneo, and the Philippines. Its wingspan is about 63 mm. It is a medium-sized butterfly with black wings on the upper side and a lapis lazuli white band running along the outer side, making it very distinctive and there are no other similar species in Japan or neighboring areas. The underside of the wings is like a dead leaf. It is a sensitive butterfly that flies quickly, so it is not easy to catch it. It gathers on rotting fruit and tree sap, but does not usually come to flowers. In the warm areas of southwestern Japan, it usually occurs three times a year (June to July, August, October), but in cold areas such as Hokkaido, it occurs once a year. The larvae feed on plants of the lily family, such as Siberian laurel, Japanese silverleaf, Japanese laurel, lesser cuckoo, and various lilies. Like the closely related butterflies and hawkweeds, they overwinter as adults.

[Takashi Shiramizu]

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

昆虫綱鱗翅(りんし)目タテハチョウ科に属するチョウ。日本では北海道より八重山(やえやま)列島にわたって分布は広いが、とくに普通のチョウというわけではない。国外では朝鮮半島、中国、台湾よりインドにかけて分布、またスマトラ島、ジャワ島、ボルネオ島、フィリピンなどのマレー諸島の山地にも産する。はねの開張は63ミリ内外。中形のチョウではねの表は黒色、瑠璃(るり)色を帯びた白帯が外側を走り、きわめて特徴があってこれに紛らわしい種は日本およびその近隣地域には存在しない。はねの裏面は枯れ葉状。敏感なチョウで飛び方も速く、これをとらえることは容易ではない。腐果や樹液に集まるが、普通は花にこない。日本西南部の暖地では普通年3回（6～7月、8月、10月）の発生であるが、北海道あたりの寒冷地では年1回の発生となる。幼虫の食草はユリ科のサルトリイバラ、シオデ、ヤマガシュウ、ホトトギス、各種のユリ類など。近縁のキタテハ、ヒオドシチョウなどと同じく成虫の状態で冬を越す。

［白水　隆］

出典　小学館　日本大百科全書(ニッポニカ)日本大百科全書(ニッポニカ)について　情報 | 凡例