Gray Matter: North American Geometrid Moths

We are launching a series of Expeditions called Gray Matter: North American Geometrid Moths! In this new expedition you will see multiple species and genera of North American Geometridae. This collection was curated by one of the North American experts, Dr. Charlie Covell.

The name Geometridae is derived from the Greek words “geo” (earth) and “metron” (measure). The caterpillar appears to ‘measure the ground’ as it moves, like a tiny walking tape measure, one inch at a time hence the name “inchworm”. Although the adult moths are often gray, and less colorful than their butterfly counterparts, they are widespread moths that are ecologically and economically important. Some Geometridae, such as cankerworms, are destructive pests of hardwood trees. Biston betularia moths (included in this expedition), have light and dark wing phenotypes, which have been used to study effects of industrial pollution. Their caterpillars also have multiple phenotypes; they can mimic different colors of twigs in order to more effectively camouflage on their host plants.

It is important to remember that you will be looking at two images per moth, dorsal and ventral. The reason for this is because there sometimes is critical information on the back of labels. So be sure to check both images! While checking both images, look at the amazing shapes and minute coloration of the moth. Thank you so much for your help!

— Laurel Kaminsky

Digitalization Coordinator, McGuire Center for Lepidoptera & Biodiversity