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Black Swallowtail Caterpillar (Mummified Remains)

Papilio polyxenes


This is the mummified host remains of a black swallowtail caterpillar that was parasitized by a mummy-wasp (Aleiodes sp.). It had a smooth, white cuticle with a darker and densely wrinkled anterior end and a hole on the dorsal surface. Aleiodes wasps are koinobionts, which means that the host caterpillar is not permanently paralyzed, but continues to feed and grow for a period of time after being parasitized. They are also endoparasitoids (they inject the eggs into the host's body). Once the eggs hatch inside of the host caterpillar, the Aleiodes larvae feed and pupate within the shrunken and mummified host caterpillar. Finally, the wasps exit from the host mummy through a circular dorsal hole. The actual mummification of the caterpillar is hypothesized to be caused by the physical elimination of the host’s corpora allatum by the parasitoid larvae. Removing the corpora allatum would reduce the juvenile hormone levels in the host caterpillar and therefore induce the formation of a pupal cuticle, resulting in a hardened cuticle.


Adhered to a fennel plant in a rural garden. This mummy was on the same fennel plant as this Black Swallowtail caterpillar:


I think the caterpillar mummy in this spotting was possibly parasitized by Aleiodes parasiticus.

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maplemoth662 6 years ago

Your welcome, Christine....

Christine Y.
Christine Y. 6 years ago

Thanks flowntheloop and maplemoth for your comments!

maplemoth662 6 years ago

Your Spotting, is a masterpiece of "beauty and words"....

maplemoth662 6 years ago

Four, very beautiful photos....You wrote a very beautiful, and a very descriptive description....

maplemoth662 6 years ago

I am lost for words....Your Spotting Is Amazing....

flowntheloop 6 years ago

So friggin' cool, Christine! <3

Christine Y.
Christine Y. 6 years ago

It's a caterpillar mummy!

Christine Y.
Spotted by
Christine Y.

Connecticut, USA

Spotted on Nov 3, 2017
Submitted on Nov 16, 2017

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