Daiō-Yanma

Daiō-Yanma (大王ヤンマ, lit. "great king hawkers") is a type of bug inhabiting the Toxic Jungle in the film Nausicaä of the Valley of the Wind.

About
It is about the same size as humans.

It often forms swarms.

It quickly reacts to events happening in the Toxic Jungle and calls other insects, hence being called the "Watcher of the Forest".