what is this???
I live in northern MI and this is the first time I have ever seen this insect. It(they) are bunched together on my young pampas grass. Do they sting, should I take measures to exterminate them? Please help me… Thank you very much.
After requesting assistance from Eric Eaton, we scoured BugGuide pages and located the Five Banded Tiphiid, Myzinum quinquecinctum, but there isn’t much explanation of this behavior. Hopefully Eric Eaton will provide something. The life cycle information provided on BugGuide states: “Life Cycle Larvae are parasitoids of white grubs (scarab larvae), especially May Beetles, Phyllophaga . Female lays one egg per grub in soil. Larvae hatches, penetrates host, first feeding on non-essential tissues, later feeding on essential organs and killng host. Pupae overwinter in soil and adults emerge in early summer, with one generation per year.” This indicates these are not social wasps, so the aggregation behavior is intriguing.
Update: (07/10/2007) Eric Explains
The wasps in the image are all males. Males of many kinds of wasps form “sleeping” aggregations like that depicted in the image. It may also be that these male wasps form “leks,” meaning they occupy a small area (lek) that the females will visit to select a mate. While the genus of these wasps certainly is Myzinum, species determination is difficult even with specimens, and certainly cannot be concluded from a photo alone.
Update: (07/10/2007) Five-banded Tiphiid from Michigan
I am also from Northern (Lower) Michigan, and I have been seeing congregations of these insects for a couple of years now in the late summer, normally on leafy indigenous grasses (the pampas grass from the inquery fit well.) It’s nice to see someone else curious about them, and I’m happy that I can add them to my numerous “natural” pest removal measures living in my neighborhood (I’ve grown out an acre of “prairie” in my back yard to foster habitat for everything from toads to dragonflies, monarchs to tiphiids… apparently.) Anyway, they never seem to be doing anything in these gatherings (not mating nor feeding on the grasses,) and I never bothered them… so they never bothered me. I just wanted to lend credence to their congregal nature, even if they are just “hangin’ out” with some grass. (Far more drug-referenced than I was shooting for…) Thanks for the always enlightening read,