For more than 40 years, nobody could find it. Then, on the last night of his search, a Delaware scientist looked out over an overgrown meadow and saw a flash he recognized instantly.
“I was confident I had found the species the moment I saw the flash pattern,” said Christopher Heckscher, an entomologist and ecologist at Delaware State University, according to a Re:wild announcement released Oct. 22.
The insect is the similar firefly, Pyractomena similis. It hadn’t been documented since 1983 and was officially considered a “lost species.”
Firefly Species Lost to Science for Over 40 Years Rediscovered In a Nature Preserve in Delaware https://t.co/wYg46t5TWe
— People Pets (@PEOPLEPets) October 24, 2026
The search
Heckscher surveyed three sites between May and June 2026: Fair Hill in Maryland, and White Clay Creek and Brandywine Creek state parks in Delaware. The first two came up empty.
On June 3, the final night of his surveys, he found them at Brandywine Creek State Park. Between eight and about a dozen fireflies were flashing in a mature meadow full of shrubs, brush and low vegetation.
The giveaway was the light show. Males of this species give off short amber pulses, typically 10 to 20 in a row. Heckscher recorded the pattern, then confirmed the identification by examining one firefly under a microscope for features found only in this species. The findings were published in the Journal of Lost Species.
Earlier searches in Georgia and North Carolina had turned up nothing.
Why it hid so long
The similar firefly lives in fields and meadows near water. That sounds common, but Heckscher says real, natural meadows are harder to find than you’d think. “Most times we’re managing them for other things, maybe livestock, or we’re mowing them once in a while,” he told Men’s Journal.
The Brandywine Creek meadow, by contrast, had simply been left to grow. Heckscher believes that’s the habitat the firefly depends on.
Co-author Anna Walker of the New Mexico Biopark Society says many “lost” fireflies aren’t actually in trouble. They are lost “simply because no one has looked for them,” she said. A recent paper lists 28 lost firefly species in the U.S. and Canada, about 16% of known species. This find brings that number down to 27.
How you can help
You don’t need a lab to contribute. Researchers say ordinary people play a real role:
- Log what you see. Walker notes that species once considered lost have turned up on community science apps like iNaturalist.
- Learn your local fireflies. The Xerces Society runs a Firefly Atlas project for volunteers.
- Leave a wild corner. If you have land, letting part of a field near water grow out instead of mowing it all may give fireflies the cover they need.
The bottom line
Sometimes conservation doesn’t take a government program or a fortune. It takes a patient scientist willing to stand in a field after dark, and a patch of land that was left alone. Next summer, take a look at your own back forty. You never know what’s flashing out there.
https://people.com/firefly-lost-to-science-rediscovered-in-nature-preserve-in-delaware-12190438