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Wasp visiting swallowtail chrysalis

Wasp visiting swallowtail chrysalis
Alameda County, California, USA
June 1, 2013
Size: <3 mm bl, not measured
This wasp was repeatedly found on or near a 1-day-old Anise Swallowtail chrysalis over a period of many hours. Parasitoid seeking host?


You're exactly right. In fact, most pteromalid species are gregarious ectoparasitoids of larvae and pupae of Lepidoptera.

See reference here.

Thank you for the ID
Thank you for the ID. I killed the wasp yesterday. Can you tell whether "my" butterfly is doomed after one day's exposure to it? I take "ectoparasitoids" to mean that this isn't the kind that inserts eggs into a pupa, but I'm not sure. I did wonder why, if the wasp was female (though with no conspicuous ovipositor) and had laid eggs, she was still hanging around.

The chrysalis is exposed; it's attached to a fence. I can't move it to a terrarium for protection. I plan to build an enclosure around it to keep out further enemies.

If eggs were laid on the surface of the pupa, there is the possibility that wasps will hatch out and the larvae will then consume the pupa. If you plan to protect the pupa from further onslaught, then other predators and parasitoids that may be around will be excluded from attacking these eggs or emerging larvae. This is the reason why some females hang around after oviposition - to protect their offspring from egg parasitoids.

There is a webpage discussing this process here.

Parasitized after all
I didn't enclose the pupa, and the wasps won. Additional images are here:


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