Firefly Species Lost to Science for Over 40 Years Rediscovered In a Nature Preserve in Delaware

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• Entomologist Christopher Heckscher rediscovered the once "lost species" of the Pyractomena similis firefly in a Delaware meadow during the spring of 2026

• He identified the species, which hasn't been seen since 1983, by its distinctive amber flash pattern

• Heckscher later confirmed it was the suspected species by examining it under a microscope

A firefly species believed lost has been rediscovered after 40 years.

Delaware State University entomologist and ecologist Christopher Heckscher discovered Pyractomena similis in a Delaware meadow between May and June 2026, according to a newly published paper in the Journal of Lost Species .

The firefly, part of the Lampyridae family, was last documented in 1983 in both the U.S. and Canada and was considered a "lost species" in 2026—meaning no one had recorded an observation of the animal for years.

Heckscher said he made the discovery because of the firefly's recognizable flash pattern. "The amber color of the flash and the long rhythmic pattern did not match any other firefly I was familiar with in this region," he said, according to a Re:wild release obtained by PEOPLE. The flash pattern, emitted by males, usually consists of 10 to 20 pulses in quick succession before it breaks and resumes.

He continued to search for the species in various meadows and fields in Maryland and Delaware. He went to Brandywine Creek State Park in Delaware, where he saw about eight to 12 fireflies flashing.

He later confirmed it was the suspected species by observing it under a microscope and examining its species-specific genitalia.

While he noted that "there's hardly any information out there about it," he said scientists know the fireflies typically live in meadows near water, but that habitat is "not terribly common," Heckscher said.

"We think of fields and open meadows as being pretty common, but most times we're managing them for other things, maybe livestock, or we're mowing them once in a while," he said. "The fact that this was just allowed to grow naturally as a meadow, that's probably what this firefly is keyed in on in terms of its habitat."

The paper also noted that in the U.S. and Canada, 69 firefly species are known, but 48 have no data at all.

Across North America, the National Wildlife Federation reports over 170 firefly species . The finding marks the rediscovery of one of 28 firefly species considered lost, or 16% of known species, research paper co-author Anna Walker said.

"They are not usually lost because they have declined or are threatened, but simply because no one has looked for them," Walker, a species survival specialist for invertebrates at New Mexico Biopark Society, said.

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"The rediscovery of Pyractomena similis is a good example of what we can expect for many of the lost firefly species if we are willing to just go out and look," she said. Walker added that we could "rediscover the vast majority of" fireflies if we created the resources to do so.

"Community science is a powerful resource as well," Walker said. "We need all the help we can get to better understand our firefly fauna, and community scientists are an irreplaceable resource in the effort."

Read the original article on People