Which parasitoid?

A parasitoid maggot or larva emerges from your caterpillar or chrysalis. What is it? How can you tell?

Here are a few tips about the parasitoids you’re most apt to see.

From caterpillars:
Tachinid fly maggots/larvae (some species leave via a mucus strand that dries into a white string)
Braconid wasp larvae (which then make their cocoons on or near the caterpillar)

From chrysalises:
Tachinid fly larvae
Trogus wasp larvae (normally from swallowtail butterflies)
Chalcid wasp adults

If a chrysalis breaks open, you may see chalcid larvae in it. Chalcid larvae do not emerge from a chrysalis. Only adults emerge from a chrysalis. Click here to see chalcid wasps leaving a Monarch butterfly chrysalis.

Click on this sentence to see a maggot moving after leaving a dead moth caterpillar.

There are many parasitoid/parasite species other than these few listed.