Missing wings on an ‘alien’ beetle pose an evolutionary puzzle

The insect in the collection of young specimens at Lund University in Sweden looked out of place.

“Well, this is a joke,” Vinicius Ferreira, an insect taxonomist and evolutionary biologist, he said to himself. “It’s a joke – it’s humor.”

The beetle—found in 1991 in Oaxaca, Mexico, just a tenth of an inch wide, among the leaf litter of the ground of pine and oak forests at more than 9,500 feet by naturalist Richard Baranowski—was decidedly male. But it was missing one of the animal’s defining characteristics: the tough outer covering known to scientists as the elytra.

After careful analysis Dr. Ferrera Description of the insect this month in the Linnean Society’s Journal of Zoology as a previously unknown but “extraordinary” species of elytra beetle: Xenomorphon baranowskii.

“Boom. We found this really strange animal. An alien beetle,” Dr. Ferreira said, choosing a name that honors Dr. Baranowski and also mentions the “exotic” in his favorite sci-fi movie franchise.

“We finally found one. I think it’s very exciting,” he said. Michael Ivey, curator of entomology at Montana State University who was not involved in the research. “This is a wonderful beast.”

“We can’t do much yet, but until this discovery, we didn’t know there was something to look for,” he added.

Wings consume a lot of energy, so over the course of evolutionary history, many species of insects have lost the ability to fly independently. But there are more than half a million known species of beetles, and to date, all of them have had at least some form of hard elytra. Even when it is not used for flight and is fused together, the shell-like wing cover is thought to be one of the keys to the beetle’s survival. It protects their soft bodies and allows them to squeeze into small crevices and get out of dangerous situations.

In the case of Dr. Ferreira’s alien beetle, he and his colleagues speculate that quitting flight and discarding the elytra could be a preventative measure to avoid high winds at the higher elevations in which they live.

Dr. Ferreira also linked species to a poorly understood evolutionary tendency studied by He et al It is called paedomorphosis. In this phenomenon, the adult females of some beetle species retain some of their juvenile features, appearing more like larvae and sometimes losing their wings. The winglessness of male Xenomorphon baranowskii is similar to that found in females of these beetles.

But usually, male beetles use their strength of flight to chase females out of sight to mate. So if beetle penetration is indeed puzzling in female beetles, it makes even less sense that male beetles will not develop wings when they become adults. “It’s the most extreme example of widespread epidermal hyperplasia,” said Dr. Ferreira.

“It’s not good for you to be in control,” he added, because it leaves individual beetles more vulnerable to threats, and unable to get very far. But, his team hypothesizes, the loss of front wings and the ability to move could allow beetle species to become more specialized and to occupy a small geographic area more successfully.

These findings could serve as an example of how highly adaptable beetles can be throughout their evolution—a trait that makes them one of the most successful animals on the planet. “This is an extreme situation,” he said. Robert Anderson, a researcher at the Canadian Museum of Nature who was not involved in this study. “Obviously, that’s the way up there in terms of weirdness.”

The description is also based on a single Xenomorphon specimen, and although entire species of insect are often described from one-off finds, researchers know almost nothing else about the animal. Its DNA cannot be studied, there is no data on its life history and no trace of what females of this species might look like. The next step will be to hike this Mexican mountain in hopes of finding more beetles devoid of elytra.

“I honestly knew this would eventually happen one day,” said Dr. Ferreira. “It’s really baffling, but anything is possible with ladybugs.”