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Photo#1079802
Larval/Pupal mud chambers constructed on twig - Eumenes

Larval/Pupal mud chambers constructed on twig - Eumenes
Near Edgewood County Park, San Mateo County, California, USA
June 2, 2015
Two of the three pupae are visible in my palm, the third is still in the cavity of the chamber here. The longer pupa is approximately 6mm (using a 10mm size for the chamber, based on comparison to my thumbnail in the 1st photo of the series...which is 15 mm long).

Images of this individual: tag all
Larval/Pupal mud chambers constructed on twig - Eumenes Larval/Pupal mud chambers constructed on twig - Eumenes Larval/Pupal mud chambers constructed on twig - Eumenes Larval/Pupal mud chambers constructed on twig - Eumenes Larval/Pupal mud chambers constructed on twig - Eumenes

I think these may be parasitoid (fly?) pupae
According to Eric Eaton's comment here, Eumenes provision each nest with a single egg/larva. That got me thinking the 3 pupae in my post may be those of parasitoids...either on the Eumenes larva, or the caterpillars that its mother provisioned the nest pot with. The appearance of the Eumenes larvae and pupae in the thumbnails below seem to reinforce that hypothesis:

    larvae:             pupae:  

The pupae in my photos look like dipteran to me.

 
They do look dipteran
Did you keep them to see what emerges?

 
Yes, I have the three pupae
I hope they eclose and will photograph them if they do. But I'm not that lucky (or skilled) when it comes to rearing insects.

 
Cyclorrhapha
Yes, they are cyclorrhaphan Diptera puparia. It would definitely be interesting to rear them out. I suspect they will turn out to be satellite flies (Miltogramminae).

 
Yes, I was thinking a tachinid
...from the caterpillar prey provided by the female wasp for her larva. And Miltogramminae seems a very good bet...thanks, Matthias!

There are lots of posts of tachinid puparia somewhat similar to mine:

             

I do have the 3 puparia in a plastic salsa container with the lid slightly ajar to allow air exchange. I put it on top of my fridge, so I'll see it every day and can check if anything emerges. But reading the comments for the posts above, it seems many people hoped to see an adult emerge...but few if any succeeded! Any specific suggestions on how to care for the pupae to improve chances of eclosure would be appreciated (i.e. is light up to 18 hours a day, heated indoor ambient temps, and relatively dry indoor air OK?)

I noticed that Lynette has an old post of a Eumenes pupae with another puparium similar to mine right next to it:

   

I wonder what happened to the Eumenes larva in the nest pot I opened? (The pot had no exit hole.) Perhaps the fly larvae consume the wasp larva first, so it won't compete with them for the caterpillars? Most (non-miltogrammine) caterpillar-feeding tachnid larvae might not be "programmed" to do that, but Miltogramminae are presumably adapted to having a hymenopteran larval competitor present.

Moved
Moved from ID Request.

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