A toggleable option for those of us who don’t enjoy hunting down each and every single fungaloid/ant/giant bee, etc. after killing the “queen” creature. Would cause all creatures associated with the queen’s nest to die off over the course of a day after the queen is dead. Or, at the very least, stop reproducing; many times I have eliminated a fungal tower only to see the surrounding terrain become completely fungalized anyway.
That is very arcadey and bossfightey and i love it.
Arcade/bossfight is why it’s not going to happen that way.
Triffids are planned to go “feral” and attack everything in sight once the Heart dies, but the Mycus doesn’t rely on its spawners for centralized command so there’s no reason they’d lose coordination.
By rights the ants ought to promote a new Queen if there are eggs or larvae left; the same would go for bees if there actually was a queen for 'em, but we don’t have one.
Awh. That’s a better idea though! 
They should take a hit to reproduction though. For that to work sensically they need to be reproducing instead of just appearing out of nowhere…
Leastwise in Dynamic, (I know, deprecated) that was how it worked: the spawn pool started draining rather than replenishing. Once Static gets reproduction mechanics, yeah, that’d work.