I was passing a group of small Redbuds growing in a sheltered place beside the garage, when I noticed a triangle shape in the foliage. The sight of a shape not naturally produced by growing stems caused me to stop and examine more closely. I found this looper type caterpillar apparently beginning a journey up a leaf stem. It doesn’t matter how well you mimic a twig, if you put yourself into an untwig-like position.
The caterpillar possesses a remarkable camouflage. Body form, color, pattern and texture all match components of the actual twig.
The two conical projections on the head help to identify this as a Cleft-headed Looper, the larval stage of the Pepper-and-Salt Moth. The projections remind me of terminal buds and play a part in the twig mimicry.
Located behind the head are three pairs of legs. Caterpillars sometimes appear to have many legs, but these six are the only true legs.
At the other end of the body are leg-like structures known as prolegs which are short, hook tipped appendages used for gripping. It’s not uncommon to hear a tearing sound as the ends of the prolegs are pulled from the substrate, especially if you are removing caterpillars from your clothing. The hooks work in the same manner as those found in Velcro.
Looper caterpillars lack prolegs in the center portion of their bodies. They travel in typical inchworm fashion by extending the body until the front legs get a firm grip and then bringing forward the rear end by arching the body into a loop.
Hopefully, this fellow got where he was going without attracting any predator attention to his triangle pattern. It would be best if it just stopped forming these abnormal shapes. Of course, this species is in the family Geometridae, so it’s to be expected that this guy would know a little something about Geometry.