Paleontologists Describe Beetles Found In Dinosaur Feces

Paleontologists have described for the first time an insect only found in fossilized dinosaur feces. The team found the tiny beetle, called Triamyxa coprolithica, with a few near-complete specimens and numerous isolated body parts in fossilized dinosaur feces. The near-complete specimens and numerous body parts allowed vertebrate paleontologists and entomologists to piece together a complete reconstruction of the Triassic beetle and understand its relationship to modern beetles.

Researchers on the study included entomologists from Taiwan, Germany, and Mexico, as well as vertebrate paleontologists from Sweden. The team used synchrotron microtomography, which is a process similar to CT scans used in hospitals. Using that process, the team was able to 3D reconstruct the beetles trapped within the fossilized feces, known as coprolite.

Multiple specimens were ingested by the reptile that produced the fecal matter, and a few were nearly complete, with much of the delicate legs and antennae still intact. They were preserved well enough that researchers were able to reconstruct the tiny beetle in great detail. The beetle represents a previously unknown family which went extinct but does have distant relatives surviving today.

Its surviving relatives are described as tiny and living in wet places with abundant algae. Researchers say the beetles in the coprolite were preserved similarly to how specimens are preserved in amber. Fossils found in amber typically the best-preserved insect fossils. However, fossils preserved in amber were mainly formed during relatively recent geological time frames.

The discovery of the beetle in fossilized dinosaur dung shows that coprolites could be valuable for studying early insect evolution and the diet of extinct vertebrates. The team believes the likely producer of the coprolite was a relatively small dinosaur ancestor that weighed about 15 kilograms living in Poland about 230 million years ago called Silesaurus opolensis. The small size of the Beatles leads the researchers to believe they weren't the primary diet of the dinosaur. The disarticulated remains of larger beetles that don't end up in coprolites in a recognizable shape were discovered.