noun
caddisfly; caddis fly
Refers to any moth-like insect of the order Trichoptera, whose aquatic larvae build protective cases.
川の近くでトビケラがたくさん飛んでいた。
Many caddisflies were flying near the river.
トビケラの幼虫は水中で巣を作る。
Caddisfly larvae build cases underwater.
The origin is uncertain. The kanji 飛螻蛄 literally means 'flying mole cricket', and 石蚕 means 'stone silkworm', both likely referring to the insect's appearance or larval case-building behavior.