This all reminds me of an excellent blog post I read about an army ant raid (Neivamyrmex nigrescens) passing a nest of the much larger Novomessor cockerelli-- Any army ant that got to close had to be killed, and quickly so she couldn't alert the column to the location of the nest.
There are a lot of amazing posts on this blog about ants with excellent photos:
https://tightloop.com/blog/2020/12/29/neivamyrmex-nigrescens-army-ant/