Subject: Tiniest inchworm
Location: South Central Kentucky
April 21, 2015 10:50 am
This morning I found this inchworm near my neck. We have a garden and chickens and many new fruit trees. Also there was a stray puppy here yesterday. So between all that, no clue where this came from. Found it on April 21. It has been about 65-80 degrees this last week with a LOT of rain. This worm is about the size of a thread and about 1/4 to 1/2 inch long. It is black with no markings visible to the eyes. The pic isn’t very good cuz the camera couldn’t focus close enough. Thank you for your reply but I understand if you don’t… Have a good day!
Though we are unable to provide you with a species identification, we are able to provide you with a response. As you have indicated, this is an Inchworm or Spanworm in the family Geometridae. The larvae from this family is characterized by having only two pairs of prolegs, three pairs fewer than most caterpillars, hence their locomotion is affected. They move by a looping action as your image indicates. Here is the explanation on BugGuide: “[Geometridae Larvae] generally have only two pairs of prolegs (at the hind end) rather than the usual five pairs in most lepidoptera; the lack of prolegs in the middle of the body necessitates the peculiar method of locomtion, drawing the hind end up to the thoracic legs to form a loop, and then extending the body forward.” This Inchworm probably fell from a tree in your garden.