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Photo#1436982
galls on goldenrod - Procecidochares atra

galls on goldenrod - Procecidochares atra
Cross Plains, Dane County, Wisconsin, USA
September 5, 2017
Showy Goldenrod - Solidago speciosa

Images of this individual: tag all
galls on goldenrod - Procecidochares atra galls? on goldenrod - Procecidochares atra wasp  - female wasp  - female

Moved
Moved from Unidentified Galls.

phyllody?
I wonder whether these rosettes on the goldenrod are just an example of phyllody and that the wasps emerged from something else hidden among the rosettes. By any chance do chalcids parasitize Agapostemon bees? Reason I ask is that there is a dead bee hidden among the rosettes which looks like it may be an Agapostemon. I have to add another photo of the rosettes since the one where the wasps were found is from another plant -- same species of goldenrod but a different and smaller collection of rosettes. Or should I just replace this photo with the correct photo?

I think I'll just let these sit for a few more days since I just checked another one of these goldenrod galls or whatever they are and more tiny wasps are showing up in that bag, too, along with a small dark, dead bee.

 
phyllody?
I'm not familiar with anything other than gall-inducing flies that would cause a goldenrod to look like this. Over the weekend I picked apart what I think was a Rhopalomyia rosette gall, and it almost appeared that there were no larvae or larval chambers inside--but then I finally found tiny midge larvae.

I'm not aware of any chalcids that would emerge from adult bees. This eurytomid looks like a typical gall parasitoid.

The added photo also looks like Procecidochares to me.

Rosette galls
I think this is Procecidochares (atra?), but having a look inside would help to rule out a cecidomyiid of some sort. I don't recognize the goldenrod; it may not be possible to ID without close-ups of flowers and leaves.

 
wasps emerging
I collected this gall on 09/08/17 and kept it in a plastic bag. Yesterday (09/17/17) when I checked there were a couple of small Chalcid wasps in the bag. Today there are 5 that I could see. I'll post some photos later. I have kept the wasps in the bag. I haven't seen any flies emerging. Would it help to send samples to anyone?

 
Netta Dorchin
is the expert on goldenrod galls... she may recognize this from the photo. Unfortunately she is in Israel, so sending samples isn't cheap. Her contact info is here.

The chalcids probably won't help in identifying the gallmaker.

 
galls and wasps
I'll take more photos. There were 6 rosettes of leaves on the gall and I counted 5 wasps although there may be another one hidden in the leaves.