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Istocheta aldrichi

Istocheta aldrichi
Kennebunk, York County, Maine, USA
June 28, 2012
Among the japanese beetles that I collected today, almost all of them had at least one parasite egg. I'm going to try to raise a few to see the adult fly.

I tried last year, and the puparia dried out. I'd recommend keeping the beetles on some slightly moist soil so that the fly larvae can burrow in when they emerge.

Will do. I've got 5 beetles, and 3 appear to be dead. The other 2 are still moving.

So maybe the larvae are pupating inside the dead ones. It may be a good sign.

The larvae exited the beetles to pupate
when I tried to raise them. I don't remember how long after the beetles died that happened.

Fact sheet
Then, maybe the fact sheet on the info page is wrong.

Fact sheet info
I collected some more last week, and the beetles have indeed buried themselves before dying. Next year when (hopefully) the flies emerge, I'll sift around in the soil and find out if they pupated inside or outside their hosts. It might be that they only leave the beetle if the beetle dies aboveground.

an update
When I got around to putting some soil in the container, I noticed that all the beetles were dead. One was completely hollow, and next to it, hidden in one of the rose petals that I had been using to feed the beetles, was a small red puparium. It appears to be alive, so I placed it on top of the soil with the other dead beetles.

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