noun
blue admiral butterfly
Refers specifically to the species Kaniska canace, a nymphalid butterfly. The name is a biological common name, not a general descriptive term.
ルリタテハは翅の裏が木の幹のような模様で、とまると見つけにくい。
The blue admiral has a bark-like pattern on the underside of its wings, making it hard to spot when it lands.
この公園では春になるとルリタテハがよく見られる。
In spring, blue admirals are often seen in this park.
The Japanese name ルリタテハ is composed of 瑠璃 (lapis lazuli, referring to the blue color) and 立羽 (a term for brush-footed butterflies). The exact historical derivation is uncertain, but the name is conventionally associated with the butterfly's appearance.