“We didn’t know how insects looked in the Triassic period and now we have the chance.Maybe, when many more coprolites are analyzed, we will find that some groups of reptiles produced coprolites that are not really useful, while others have coprolites full of nicely preserved insects that we can study. We simply need to start looking inside coprolites to get at least some idea.”

Martin Fikáček, entomologist, National Sun Yat-sen University, Taiwan

A new species of beetle has been discovered, preserved in fossilised dinosaur droppings aka coprolites.

The beetles were preserved in a 3D state with their legs and antennae fully intact.

The research team named the new beetle species Triamyxa coprolithica, which refers to its Triassic age and indicating that it belongs to the suborder Myxophaga–whose modern equivalents are small and live on algae in wet environments, Triamyxa likely lived in semiaquatic or humid environments and were likely consumed by Silesaurus opolensis–the probable producer of the coprolite–a beaked dinosaur ancestor about 2 meters long and 15 kilograms that lived in what is now Poland at the same time, 230million years ago.

The coprolite was scanned using synchrotron microtomography at the European Synchrotron Radiation Facility (ESRF) in Grenoble, France. The method, which works like a CT scanner in a hospital except with strong x-ray beams, makes it possible to visualize internal structures in fossils in three dimensions with great contrast and resolution.

Martin Qvarnström a paleontologist at Uppsala University, Sweden and a postdoctoral fellow in the lab of Per Ahlberg, described how amazed he was at the preservation of the beetles.

“It was like they were looking right at you. This is facilitated by coprolites’ calcium phosphatic composition. This together with early mineralization by bacteria likely helped to preserve these delicate fossils.”

“Although Silesaurus appears to have ingested numerous individuals of Triamyxa coprolithica, the beetle was likely too small to have been the only targeted prey,” says Qvarnström.

“Instead, Triamyxa likely shared its habitat with larger beetles, which are represented by disarticulated remains in the coprolites, and other prey, which never ended up in the coprolites in a recognizable shape. So it seems likely that Silesaurus was omnivorous, and that a part of its diet was comprised of insects.”

Martin Fikáček added:

“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.

“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 finding appears June 30 in the journal Current Biology.