Parasitized Inchworm with Chalcid Wasp Pupae

Subject:  Stickbug?
Geographic location of the bug:  Silver Spring, MD
Date: 08/12/2018
Time: 12:14 PM EDT
Your letter to the bugman:  Found this in the back yard.  Looks like there maybe eggs on its back.  Is it going to mess up my garden?
How you want your letter signed:  Gene

Parasitized Inchworm with Chalcid Pupae

Dear Gene,
Your “stickbug” is an Inchworm or Spanworm, the caterpillar of a moth in the family Geometridae, and they are excellent twig mimics.  What you have mistaken for eggs are actually the pupae of parasitoid Chalcid Wasps.  Here is a similarly parasitized Inchworm on BugGuide and here is an image of the Chalcid Wasp that emerged, also on BugGuide.

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