Thanks for sharing! Something else to be on the look out for.

Yes, it's true that Trichogramma only mess with the eggs. So, even if you're mad at the Trichogramma, get over it. It was a different critter that killed your cat.

So in spite of what you "learned" and saw in the image at your link, that's not a Trichogramma wasp. Trichogramma are bitty little wasps, with much more simple wings.

Here's a link to UCD info
http://www.ipm.ucdavis.edu/PMG/NE/trichogramma_spp.html

And this link shows an illustration
http://thailand.ipm-info.org/natural_enemies/parasitoids/trichogramma.htm

And here's a life cycle illustration from the Encyclopedia Britannica.
http://media-2.web.britannica.com/eb-media/49/6549-004-1D2F6354.gif

Notice that the pupa is inside the cat's egg rather than exterior to the cat.

Here is a link that might be useful: {{gwi:549194}}

Jean, thanks for the info. So do you know what it was that killed my cats?

Well, if they're the same as pictured on the web site you linked, likely a small parasitic wasp -- but larger than Trichogramma -- with the technical name Apanteles.

Thanks again, I believe I found it:

Ichneumon Wasps - Gambrus nuncius (Say) are about 5/16 inch long, reddish-black (basal half of abdomen reddish and rest black with a whitish yellow mark at the tip in females). The first segment of the male abdomen is black. This parasite attacks caterpillars of swallowtail butterflies.

Here is a link that might be useful: Parasitic wasps

I have definitely learned something from this thread. Thanks to both of you for posting. I didn't realize eggs could be parasitized.

it would not have been G. nuncius as they do not parasitize in that way (their larvae remain inside the cocoon and fill it. They then emerge in the spring. Google it and you should be able to find pics or go to buggude.net) and go after promethea moths. Trogus pennator are regular parasitoids of the swallowtail family and frankly are lovely ichneumon wasps but are single and merge from a large single hole in the side of the chrysalis. Keep in mind that these are native and belong here just as much as the butterflies do. I know it is hard to see at times, but nature up close is not always pretty. I raise silkmoths and it took me a couple seasons to appreciate it all.

Before you flame me ;) there are plenty that you CAN hate, though it is us humans that introduced them in the first place, such as the tachinid fly, Compsilura concinnata, which was introduced to to keep the gypsy moth in check. Now THERE is a parasitoid that is wreaking havoc on lepidoptera, some species of hymenoptera(wasps/bees) and coleoptera as well(beetles).

But I know exactly how you feel because a number of years ago I lost almost every Anise Swallowtail butterfly cat to a parasite that would kill the cat usually within the first or second instar, probably the second, in the same way. I would watch the cat feed normally for a while and then it would stop eating and just sit motionless for days and then one day it would be still sitting on the stem but looking sort of shrivelled up and there nearby would be a tiny beige cocoon. It would not have bothered me so much had it not taken all but one cat over an entire season. I almost gave up on the butterfly stuff after that season. Unfortunately, I live in a somewhat agricultural environment so there is not much one can do if people decide to import preditory insects to control what they consider pests. The worst part of the experience was that the cats had come from a number of places in my area and had nevertheless managed to come in contact with the same parasites. For awhile I feared that the Anise Swallowtails might never survive or that the other butterflies would be killed off also. Thank God I was wrong. I have not had the problem since.

I don't know what to say beyond that except that I am not capable of being neutral about the whole food chain thing. It is what it is. Murray

Thank you so much for this information!! For the first time my husband built an elaborate cover for our fennel that had about 7 small anise swallowtail caterpillars. Slowly each one disappeared, the same problem that we had last year. I finally took the last one inside. It didn't seem active and just a moment ago I noticed that there was a small yellow "cocoon" next to it, the same type that I saw outside on the fennel. I thought there was a correlation but couldn't figure it out. Well now I sadly know what the problems is. Thank you again. The internet is amazing------information at your fingertips!!