The Purdue Plant and Pest Diagnostic Laboratory

P&PDL Picture of the Week for
October 3, 2005

Giant Night Flying Moths

Tim Gibb, Insect Diagnostician, Department of Entomology, Purdue University

Polyphemus is the name of one of several species of large night flying moths that belong to the giant silkworm moth family (Saturniidae). These moths may have wingspans in excess of 5 or 6 inches. Mid summer and fall is a common time for homeowners to call in and report these moths found in early mornings on a window screen or door or even driveway close to the home.

These large and colorful moths often attract attention, not only because of their size and coloration, but also because of the distinct eye-spots on the wings. With only a small amount of imagination, one can imagine the eyes forming a part of a face, complete with pupils, eye-brows and even a nose.

Survival theory suggests that when the moth spreads its wings and unveils the face, it startles any would be predators, or curious kindergarten children, for a second – just enough time for the moth to complete its escape.

What evolutionary theory does not take into account is the fact that the spots are so beautiful that even amateur collectors go to great lengths to chase these moths down, contain them in a bottle or place them into a freezer and then pin them to the bottom of a 4-H insect collection box. Perhaps this is a case of evolution having out-smarted itself.

Click image to enlarge

Purdue Plant & Pest Diagnostic Lab Purdue Cooperative Extension Service