Esnsign wasps are one such example. This summer alone, I’ve had many send me pictures or samples asking what these little wasps are. I've even noticed a few more of them resting on walls in buisness buildings and the like. Not surprising given that they parasitize American Cockroach egg cases (ootheca) and American Cockroaches love humid,moist environments - which we experienced earlier this summer.
Ensign wasps are blackish blue wasps that almost look like a hybrid between a wasp and a cricket.
Ensign wasps tell you that American cockroaches are close by. They parasitize the cockroaches by laying their eggs in the egg cases of American cockroaches, preventing the roaches from hatching.
Ensign wasps are actually good to have around, but usually mean you have another issue going on. If you find these inside the home, you can be pretty sure that you have American Cockroaches. Leave the wasps, they will help reduce the cockroach population!