Giant Lacewing (Polystoechotes punctata)

Dear Readers, this is a rather interesting tale, and I am still not sure what the moral of the story is, so I will leave it to you to decide.

Back in 2012, PhD student Michael Skarvla was shopping in his local Walmart in Arkansas when he saw a gigantic insect sitting on the wall outside the entrance, minding its own business. So, as entomologists do, he picked it up, held it in his hand while he did his grocery shopping and took it home.  At this point he thought it was an antlion, a fairly common insect, and so he killed it, preserved it and stuck it into his insect collection.

Antlion (Distoleon tetragrammicus) Photo by Entomart.

For those of you who would rather see your insects alive, I agree. There are arguments for specimen collecting (for one thing, it’s often the only way to tell different species apart, and often if you want to preserve a habitat, you have to know and be able to prove what’s living there). Whether this applies to the entrance to Arkansas Walmart, I’ll leave you to judge.

Fast forward to 2020, and Skarvla is teaching a course on insect identification by Zoom. He pulls out this insect and starts to explain that it’s an antlion, before falling silent in front of his students. He realises that what he’s looking at is in fact a much rarer insect – a giant lacewing (Polystoechotes punctata). You might be familiar with the green lacewing that sometimes pops up inside the house on a summer’s night, but this is a much bigger critter, with a wingspan of up to 6.5 cm.

Green lacewing (Chrysoperla carnea)

Giant lacewings had suddenly disappeared from the east coast of North America – one hadn’t been seen for more than 50 years, until Skarvla discovered his specimen. He suggests that there is a small population of the insects in the nearby Ozark mountains, and maybe in a number of other places, although whether they’re still there, eleven years after the Walmart specimen was found, is anyone’s guess. The reasons for their sudden decline are unknown, but it’s been suggested that light pollution, urban development and invasive species might all have played a part.

The species first arose way back in the Jurassic, and is part of a group known as the Neuroptera, or net-winged insects. They are all carnivorous, with the larvae being exceptionally voracious with enormous prey-sucking jaws.

Neuroptera wing preserved in Baltic amber (By Makarkin, Wedmann, & Weiterschan 2014 – Makarkin, Vladimir N., Wedmann, Sonja, & Weiterschan, Thomas. (2014, December 31). FIGURE 1 in First record of the family Ithonidae (Neuroptera) from Baltic amber. Zootaxa. Zenodo. http://doi.org/10.5281/zenodo.227659, CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=104134457)

And so, this is how science proceeds – a chance discovery outside a suburban supermarket leads to the realisation that an insect that it was thought had been extinct in the area for over 50 years turns out to have been around all along. It just goes to show how much there is to discover in the seemingly unpromising habitats in our towns and cities. There is still so very much that we don’t know.

You can read the whole New Scientist article here.