Caterpillar - Microplitis

Moved

Moved from Cocoons and parasitized caterpillars. In re-reading my notes I saw that Microplitis cocoons start out whitish like this one (they end up brown), which removed the lingering bit of uncertainty I had.

… Charley Eiseman, 12 December, 2008 - 6:52pm

Moved (again)

I've done some digging, and I'm satisfied that this is a braconid (note that the previous move was to Ichneumonoidea, which includes both ichneumonids and braconids). I'm also pretty well convinced that the wasp belongs to the genus Microplitis (of the braconid subfamily Microgastrinae), but to be conservative (for now) I'm dumping it with all the other photos of caterpillars with braconid cocoons. I've found a few sources that describe species of Microplitis as having ribbed cocoons, and the one illustration I found very closely matches your cocoon. The species of which I found descriptions are parasitoids of noctuid caterpillars, which is encouraging, and also one is described as making a cocoon that is 5-6 mm long (as yours seems to be), which is unusually long for a braconid cocoon (almost all that I've seen are about 3 mm long).

I'm not sure how long this link will last (it's a Google book search), but the illustration is on page 121 of:
Quaintance, A. L. and C. T. Brues. The Cotton Bollworm. U.S. Department of Agriculture Bureau of Entomology Bulletin No. 50. Washington: Government Printing Office, 1905.

… Charley Eiseman, 9 October, 2008 - 12:15am

Microplitis

Thank you for this discussion, which helped me identify a nearly identical observation I made last month on iNaturalist. https://www.inaturalist.org/observations/119872925

… Larry Jensen, 8 June, 2022 - 7:28pm

Microplitis

This is excellent. Thanks

… David E. Reed, 9 October, 2008 - 7:59am

Moved

Moved from Cocoons--I had forgotten that there are no images there anymore.

I've followed v belov's suggestion because I agree, there don't seem to be any other options, but with the caveat that I have never seen a cocoon that remotely resembled this before. David, if you find another one of these, it would be fantastic if you could save it in a container and get a photo of whatever comes out.

I will likely have occasion over the next few months to get in touch with braconid & ichneumonid specialists, and if I do I will direct them to this photo to see what they make of it.

… Charley Eiseman, 8 October, 2008 - 6:53pm

Ichneumonid

Thanks for the suggestion. I certainly will collect if I find one next year.

… David E. Reed, 8 October, 2008 - 9:48pm

Moved

Moved from Ants, Bees, Wasps and Sawflies.

… Charley Eiseman, 8 October, 2008 - 6:50pm

i'd suggest moving it to Ichneumonoidea page

… v belov, 8 October, 2008 - 6:31pm

Wagner's Orthosia hibisci

looks rather similar, page 418, but the one image on BugGuide is very different.

… john and jane balaban, 27 May, 2007 - 8:41pm

Orthosia

Thanks, It does look very much like it in Wagner's and I have seen many of the O. hibisci adults in the same area.

… David E. Reed, 27 May, 2007 - 9:40pm