noun
chironomid; non-biting midge
Refers to any insect of the family Chironomidae; resembles a mosquito but does not bite. Often seen swarming near water.
湖の近くでユスリカが大量に発生している。
A large number of non-biting midges are appearing near the lake.
ユスリカは蚊に似ているが、刺さない。
Non-biting midges look like mosquitoes but do not bite.
蚊 is a biting mosquito, while ユスリカ is a non-biting midge that resembles a mosquito.
The name likely comes from 揺する (yusuru, 'to shake') + 蚊 (ka, 'mosquito'), referring to the way these insects sway or dance in swarms. The exact derivation is uncertain.