Lightning Beetles of the Great Marsh

Plenty of people enjoy the light show put on by beetles in the family Lampyridae on summer nights, but you might not know that those fireflies sparkling in the dark could be any of more than 20 species in Pennsylvania (more than 2,000 species worldwide). The lightning beetle flashing ten feet above a sedge marsh is likely a different species than the one displaying knee-high above a mowed lawn. Although lightning beetles genera can be pretty easily distinguished by looking at them, it often takes observations of flashing patterns to ID them to the species level.

In 2025 Carl Manthey led a survey of lightning beetles at the Great Marsh. Volunteers walked routes at Marshlands and observed lightning beetle flash patterns. They captured beetles and took photos of them in petri dishes. In all Carl identified seven species of lightning beetles and laid the ground for further exploration of our bright neighbors.

Read Carl’s report for the full picture. If you’d like to explore the critters of the Great Marsh, please visit our events page and be in touch at info@greatmarshinstitute.org.