Probably published in the '70s or '80s; I read it as part of a one-author collection at least 20 years ago.
In the story, the protagonist has escaped from slavery with (I think) some kind of valuable information that he needs to get to the resistance. On the run, he tries to hide in a village, and get the villagers to protect him. It turns out in the end the village ARE the resistance, and he has risked blowing their cover.
Bits I recall:
The insect 'airship': a disgusting organic gasbag-thing described as being covered with an impenetrable rind, with sphincters that open to allow the insects in and out.
The insects who come for the prisoner, buzzing and dancing, hopping over each other.
A description of how the insects are violating Earth, getting their human slaves to dig deep tunnels into which they then force gigantic versions of their insect selves for reasons unknown.
All the stories in that book are a total mind-f*ck; would really like to get a hold of it.