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New Triassic Beetle Species Found in Fossilized Poop

The discovery offers a new alternative to using amber — fossilized tree resin which only dates back about 140 million years — to learn about insect evolution.

(CN) — Hidden in fossilized poop from a close relative of dinosaurs, paleontologists have discovered a new, 230-million-year-old beetle species in Poland.

It’s the first time near-complete insects have been found in fossilized feces, making it a discovery that offers a new alternative to using amber — fossilized tree resin which only dates back to about 140-million years — to learn about the evolution of insects and food webs of certain time periods.

“This has been a very pleasant experience for me,” Martin Qvarnström, a paleontologist at Uppsala University in Sweden, said in a statement. “I did not expect that we would find almost complete beetles in a coprolite!”

Coprolite is the scientific term for fossilized poop.

It is also the first time a new insect taxon — a unit of a scientific system called taxonomy used to categorize organisms by shared characteristics — has been described based on specimens found in fossilized feces.

The new species is called Triamyxa coprolithica, indicating that it’s from the Triassic period — one geological period before the Jurassic — and that it was found in a coprolite.

The study by Qvarnström and Martin Fikáček, an entomologist at National Sun Yat-sen University in Taiwan, was published Wednesday in the journal Current Biology.

"We didn't know how insects looked in the Triassic period and now we have the chance," Fikáček said in a statement.

Typically, amber contains the most well-preserved insect fossils, Qvarnström said, but it was mainly formed during a relatively young geological time.

“Our findings show that coprolites could be good targets for studying insect evolution prior to the large-scale formation of amber and, at the same time, the diets of extinct vertebrates,” he wrote.

To uncover the insects, researchers used synchrotron microtomography — a method that works like a hospital CT scanner but with strong x-ray beams — to see the internal structures of fossils in three dimensions and with great detail.

“So if you find an insect in the coprolite, you can scan it using microCT in the same way as we do with amber insects, and you can see all the tiny details of the insect body as we do in amber," Fikáček added in his statement. “In that aspect, our discovery is very promising, it basically tells people: ‘Hey, check more coprolites using microCT, there is a good chance to find insects in it, and if you find it, it can be really nicely preserved.’”

The beetles, some with their legs and antennae fully intact, are part of an extinct lineage but can be traced back to a suborder that includes about 120 species still in existence today.

“There are actually beetles around today that do not look too different from this beetle,” Qvarnström wrote, adding that “their modern representatives are small and generally found in large numbers on wet surfaces covered with algae.”

The beetles likely were eaten by Silesaurus opolensis — a beaked ancestor of dinosaurs that measured about 6 and a half feet and weighed around 33 pounds — that lived in what is now Poland. But because the beetles were so small and are well-preserved, it suggests they may have been accidentally eaten with algae rather than targeted as prey.

At the time of the beetle’s existence, the climate in that area was likely subtropical with alternating humid and dry seasons and possibly monsoonal, according to the study.

“There are heaps of things you can study based on fossilized droppings but it had been hard to understand what to do with it, hard to recognize what is inside, and hard to draw conclusions from it, but now there are tons of data,” Qvarnström said in a statement. “The ultimate goal is to use the coprolite data to reconstruct ancient food webs and see how they changed across time.”

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