Paleontologists discover new insect group after solving 150-year-old mystery

Scientists have for more than 150 years mistakenly classified a group of fossil insects as dam flies, the famous cousins ​​of dragonflies that fly around in wetlands and eat mosquitoes. Although strikingly similar, these fossil heads have been strangely shaped, which researchers have always attributed to deformation due to the fossilization process.

However, a team of researchers led by Simon Fraser University (SFU) paleontologist Bruce Archibald has discovered that they are not dam lines at all, but represent a large new group of insects closely related to them.

The findings, presented today in Zootaxa, shows that the characteristic shape of the insect’s non-protruding, rounded eyes, near the head, are the defining characteristics of a suborder associated with dam flies and dragonflies that the researchers named Cephalozygoptera.

“When we started finding these fossils in British Columbia and the state of Washington, we also first thought they must be dam membranes,” says Archibald.

But on closer inspection, the team noticed that they looked like a fossil that the German paleontologist Hermann Hagen wrote about in 1858. Hagen set the precedent that the fossil is linked to the damselfly suborder despite its different head shape, which does not fit damselflies at all.

Damselflies have short and wide heads with eyes that protrude clearly on each side. However, Hagen’s fossil had a strangely rounded head and eyes. But he assumed that this difference is false, caused by deformation during fossilization.

“Paleontologists since Hagen wrote that it was dam sheets with twisted heads,” says Archibald. ‘A few hesitated, but still assigned to the damselfly suborder. ‘

The SFU-led team, including Robert Cannings of the Royal British Columbia Museum, Robert Erickson and Seth Bybee of Brigham Young University and SFU’s Rolf Mathewes, sifted through 162 years of scientific articles and discovered that many similar specimens since Hagen’s time was found.

They experience a eureka moment when they realize that the strange heads of their new fossils are in fact their true form.

The researchers used the definition of the head shape of the fossil to name the new suborder Cephalozygoptera, which means ‘head damselfly’.

The oldest known species of Cephalozygoptera lived among the dinosaurs in the Cretaceous in China, and was last known about 10 million years ago in France and Spain.

“It was about 50 million years ago important elements in wetland feeds in ancient British Columbia and Washington,” says Archibald. “Why they declined and became extinct remains a mystery.”

The team named 16 new species of Cephalozygoptera. Some of the fossils were found in the traditional land of the Colville Indian tribe in northern Washington, so Archibald and his co-authors collaborated with tribal elders to name a new family of them. They call the family ‘Whetwhetaksidae’, from the word ‘whetwhetaks’, which in the language of the Colville people means dragonfly-like insects.

Archibald spent 30 years combing the fossil-rich deposits of southern British Columbia and the northern interior of Washington. To date, he has discovered and named more than 80 new species from the area in collaboration with others.