Pennsylvania firefly flashing its light; photo © E.R. Degginger/ Color-Pic, Inc. www.color-pic.com (used by permission).
Official State Insect of Pennsylvania
Pennsylvania designated the firefly, Photuris pennsylvanica (De Geer), as the official state insect in 1974. A small, unremarkable beetle by day, fireflies can transform a midsummer night into a fairyland of tiny, brilliant twinkling lights - a true wonder of nature. The firefly is also a state symbol of Tennessee. All State Insects
How did the Firefly become a Symbol of Pennsylvania?
It began when elementary students in the town of Upper Darby saw an article about Maryland adopting a state insect. Pennsylvania lacked a state insect at the time, so the students entered their selection of an insect symbol to the General Assembly. On April 10, 1974, the firefly was formally adopted by the Pennsylvania General Assembly.
Upper Darby Elementary School's Principal at the time, Thomas Hafner, and schoolteacher Debe Hill communicated with Governor Milton Shapp to make the effort successful. The students were presented with a bronze plaque in the shape of a keystone which now hangs in the front hall of Highland Park Elementary School (from: PA Historical & Museum Collection).
Commonly called "lightning bug" in Pennsylvania, the firefly produces light through an efficient chemical reaction using special organs, with very little heat given off as wasted energy. One or both sexes use species-specific flash patterns to attract members of the opposite sex (though not all firefly species are bio-luminescent as adults).
These flashing signals range from a continuous glow, to discrete single flashes, to "flash-trains" (composed of multi-pulsed flashes). In most North American species of firefly (including Photuris pennsylvanica), the males fly about flashing their species-specific flash pattern, while females are typically perched on vegetation near the ground. When a flashing male attracts a female, she responds at a fixed time delay after the male's last flash. A short flash dialogue may ensue between the fireflies as the male firefly locates her position and descends to mate.