Say’s Firefly
A dark firefly with pale margins and an angular shield pattern, Say’s firefly turns summer dusk into species-specific communication.
Artwork inspired by T.C. Steele
Fireflies are beetles, and their flashes are controlled chemical light with very little heat. Different species use timing, height, movement, and pattern to locate mates while reducing confusion. Say’s firefly honors Indiana naturalist Thomas Say, whose work helped establish American entomology.
Species-level identification from a single glow is difficult. Record the full flash sequence, habitat, temperature, time after sunset, and a clear daylight view when possible. Protect the display by reducing outdoor lighting, avoiding broad insecticides, keeping leaf litter and moist ground, and never collecting large jars of adults from one small population.
- Order
- Beetle
- Signal
- Species-specific flash pattern
- Indiana link
- Official state insect
Quick guide
- Let eyes adjust
- Wait without a bright phone screen or flashlight.
- Record the rhythm
- Count flashes and pauses rather than noting only color.
Recognize and observe
- Let eyes adjust
- Wait without a bright phone screen or flashlight.
- Record the rhythm
- Count flashes and pauses rather than noting only color.
- Photograph structure
- A dorsal view helps with the shield and wing-cover pattern.
- Darken the habitat
- Turn off unnecessary lights during display season.
Good to know
“Lightning bug” and “firefly” mean the same beetle group. Not every species flashes as an adult, and not every flash belongs to this species.
Notice these
- Beetle
- Species-specific flash pattern
- Official state insect