noun
gypsy moth; spongy moth
Refers to the moth species Lymantria dispar. The name 'spongy moth' is a newer common name adopted in some regions.
マイマイガの幼虫は木の葉を食べる。
Gypsy moth larvae eat tree leaves.
今年はマイマイガが大量発生した。
There was a large outbreak of spongy moths this year.
The name likely derives from the caterpillar's movement resembling a dancing snail (舞舞 + 蛾). The exact origin is uncertain.