Polystoechotes punctata, a species of giant lacewing, was formerly widespread across North America but was extirpated from eastern North America by the 1950s. Now, a new study reports a specimen collected from Fayetteville, Arkansas.
Scientists have found a giant insect plucked from the façade of an Arkansas Walmart that has set historic records. The discovery represents a new state record and the first specimen recorded in eastern North America in over fifty years. It also suggests that there may be relic populations of this large, Jurassic-Era insect yet to be discovered.
The specimen was initially found in 2012, but it was misidentified. Michael Skvarla, director of Penn State‘s Insect Identification Lab, discovered its true identity after teaching an online course based on his insect collection in 2020.
Skvarla said, “I remember it vividly because I was walking into Walmart to get milk, and I saw this huge insect on the side of the building. I thought it looked interesting, so I put it in my hand and did the rest of my shopping with it between my fingers. I got home, mounted it, and promptly forgot about it for almost a decade.”
Skvarla tried to show the characteristics of a species he had previously called an “antlion.” Still, the traits didn’t match those of the predatory insect resembling a dragonfly. Instead, he believed it resembled a lacewing more. A giant lacewing has a wingspan of roughly 50 millimeters, which is quite large for an insect, indicating that the specimen was not an antlion.
His students got to work comparing features—and a discovery was made live on Zoom.
Codey Mathis, a doctoral candidate in entomology at Penn State, said, “We were watching what Dr. Skvarla saw under his microscope, and he’s talking about the features and then just kinda stops. We all realized together that the insect was not what it was labeled and was, in fact, a super-rare giant lacewing. I still remember the feeling. It was gratifying to know that the excitement doesn’t dim and the wonder isn’t lost. Here we were making a true discovery during an online lab course.”
Skvarla and his associates examined the specimen’s molecular DNA for additional confirmation. Since determining the insect’s true identity, Skvarla has safely put it in the Frost Entomological Museum at Penn State, where scientists and students can access it.
Louis Nastasi, a doctoral candidate studying entomology at Penn State, said, “It was one of those experiences you don’t expect to have in a prerequisite lab course. Here we were, just looking at specimens to identify them, and suddenly, out of nowhere, this incredible new record pops up.”
Skvarla explained, “The fact that a giant lacewing was spotted in the urban area of Fayetteville, Arkansas, may reveal a larger story about biodiversity and a changing environment. The explanations vary for the giant lacewing’s disappearance from North America, and it remains a mystery.”
“The insect’s disappearance could be due to the ever-increasing amount of artificial light and pollution of urbanization; suppression of forest fires in eastern North America, if the insects rely on post-fire environments; the introduction of non-native predators such as large ground beetles; and introduction of non-native earthworms, which significantly altered the composition of forest leaf litter and soil.”
“Entomology can function as a leading indicator for ecology. The fact that this insect was spotted in a region that hasn’t been seen in over half a century tells us something more broadly about the environment.”
To determine the range of giant lacewings, the researchers examined vast collection records, including museum holdings and community scientific submissions. Numerous ecoregions in both eastern and western North America are represented in the records, which cover a vast geographic area from Alaska to Panama. The map revealed the Arkansas specimen was the first spotted in eastern North America in over 50 years.
According to Skvarla and his co-author J. Ray Fisher of the Mississippi Entomological Museum at Mississippi State University, Fayetteville lies within the Ozark Mountains, which are a suspected biodiversity hotspot.
Scientists noted, “Dozens of endemic species, including 68 species of insects, are known from the Ozarks, and at least 58 species of plants and animals have highly disjunct populations with representatives in the region. They explain that the area is understudied compared to regions of similar biodiversity, such as the Southern Appalachians.”
“This combination makes the region an ideal place for a large, showy insect to hide undetected.”
Skvarla explained, “The mystery remains as to how the insect arrived on the exterior of a Walmart. The fact that it was found on the side of a well-lit building at night suggests that it was likely attracted to the lights and may have flown at least a few hundred meters from where it originated.”
“It could have been 100 years since it was even in this area—and it’s been years since it’s been spotted anywhere near it. The next closest place they’ve been found was 1,200 miles away, so unlikely it would have traveled that far.”
Scientists noted, “The new specimen represents a rare, surviving eastern population of giant lacewings that evaded detection and extinction.”
Nastasi said, “Discovery doesn’t always hold that same grasp on people that maybe it did 100 years ago. But a finding like this highlights that even in a run-of-the-mill situation, there are still a tremendous number of discoveries to make about insects.”
- Michael J. Skvarla et al, Rediscovery of Polystoechotes punctata (Fabricius, 1793) (Neuroptera: Ithonidae) in Eastern North America, Proceedings of the Entomological Society of Washington (2022). DOI: 10.4289/0013-8718.104.22.1682