What Parasitized the Smartweed Caterpillar???

Subject: unknown parasite of Acronicta oblinita
Location: Marsh in Salamonie Reservoir, NE Indiana
September 12, 2013 7:30 am
On Aug. 24 you helped my mother identify the Smartweed Caterpillar / Smeared Dagger Moth (Acronicta oblinita) that I found on a Rose Milkweed (Ascelpias incarnata) in a marsh. I collected another from a willow branch and brought it home. It stopped moving completely and even starting spinning a strange web. To my wife’s horror, dozens of small yellow parasites slowly emerged from its side as it was still (apparently?) alive. They all seemed to perish in the hot sun and the ants had a feast. Photo attached.
I searched Google Scholar for some clues…
I see a 1903 reference to a ”Rhogas rileyi Cress” being parasitic, mentioning the silk I saw (p. 24 here: http://bit.ly/1atDh3W). However, I cannot find R. rileyi Cress in recent mention so I wonder if the name has been updated. I see a recent publication noting that the parasitic wasp Aleiodes rileyi Cresson often chooses A. oblinita as a host, but it did not seem to undergo the mummification described.
Signature: Adam Thada

Parasitized Smartweed Caterpillar
Parasitized Smartweed Caterpillar

Hi Adam,
We are very impressed with your research, but in our opinion, the parasites that emerged from the Smartweed Caterpillar look more like fly larvae to us, so with that in mind, we would lean more toward this being an instance of parasitization by Tachinid Fly.  We have not been able to uncover any evidence, and that is just our first impression.  Perhaps one of our readers will have better luck determining What Parasitized the Smartweed Caterpillar?

Parasitized Smartweed Caterpillar
Parasitized Smartweed Caterpillar

Comment courtesy of Erwin
Subject: What Parasitized the Smartweed Caterpillar???
December 13, 2013 5:45 am
Going through some older posts I found one submitted on Sept.13, 2013 by Adam Thada. These parasites are Braconidae for sure. Braconidae (genus Apanteles and others) are well known as parasites of Acronycta caterpillars.
Here you can see as an example larvae of Braconidae coming out of a caterpillar of Pieris sp.
(Please scroll down)
Signature: Erwin Beyer

Hi Erwin,
Your comment was written as though you provided a link by indicating to “scroll down”.  We did not get the link.

Subject: here is the link
December 13, 2013 9:04 am
Dear Daniel,
here is the required link: http://www.ingana.de/html_insekten/hymenoptera/hymenoptera-hautfluegler-wespen-schlupfwespen.html
Signature: Erwin Beyer

The Braconids in the link you provided look exactly like the ones submitted to us.  Thanks Erwin.

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