Sometime around 8 AM on my wife’s birthday I heard the question that all Entomologists often get – “Hey, what’s this bug?” My wife has, over time, become de-sensitized to insects to some degree. To her credit, the agonizing shriek followed by “COME KILL THIS NOW” has been replaced by a genuine curiosity – unless we’re talking about a spider, of course…
This particular morning the critter in question was an interesting little wasp that’s not seen all that frequently, but is not uncommon. One of the things that makes it interesting is the way it makes a living – as a parasitoid, or an insect whose young develop in other insects or their eggs, killing them in the process. The other thing that makes it interesting is its body shape, and the way it moves. Sure, you non-Entomologists don’t usually associate the word “cute” with insects, but the ensign wasp qualifies.
Your eyes are not playing tricks on you – the ensign wasp’s
“tail” (abdomen) is the tiny flag-like thing on the end of
a narrow stalk. Photo courtesy Texas A&M University.
Why is it called an ensign wasp? The tiny tail, or abdomen, of the wasp is waved about like an ensign’s flag as the wasp runs around looking for prey. It’s difficult to describe unless you are lucky enough to observe one alive – but definitely, in my mind, qualifies the wasp as cute.
If you’re not convinced by the photograph, perhaps I can win you over to the ensign wasp’s side by explaining just what they are parasitoids of. Cockroaches lay their eggs in oothecae (egg cases). These tiny wasps, which are harmless to people, are deadly to cockroaches – they inject their eggs into cockroach oothecae, where their young are presented with a buffet consisting of 20-40 cockroach eggs. If you happen to see an ensign wasp in your home, it does not mean you have cockroaches in your home as well. They simply find their way into homes from outdoors, where they are fairly common and prey on egg cases of cockroaches that live around our homes such as smokybrown cockroaches. If you find one, you might just want to coax it into running onto a piece of paper, and releasing it outside to continue its macabre work…..after all, if you have the choice between a rarely seen, harmless parasitoid and an inch long flying cockroach, whose side are you on?
Of course, Black Pest Prevention can help ensign wasps reduce cockroach populations around your home using IPM, or Integrated Pest Management. Through judicious use of insecticidal baits, exclusion, and recommendations for making your yard less attractive to these creatures, we can reduce their numbers – reducing the chance that one will make its way indoors to “bug” you and your family.
Aug 14, 2011 at 9:28 AM I'll try to put this to good use imemdiately.