Fossils are one of the most important ways that scientists are able to discover ancient life forms that lived millions of years ago. The most famous examples of this are dinosaur fossils, which are relatively common because these creatures had large and strong bones that could survive long after death so the fossils could form.

In the vast majority of cases with soft-tissue creatures, however, the animal would completely disintegrate long before a fossil could form, so they are much less common. Fortunately for us (though unlucky for the ancient arthropod), a previously undiscovered sea creature died in just the right conditions for it to be preserved and fossilized so scientists today could discover it.

The new species is named Lomankus Edgecombei. It is in a group called megacheirans, which are anthropoids that had a large appendage. Most of the creatures in this family used that appendage to capture prey, though this one’s appendage was considerably smaller. Scientists believe that it likely evolved to sense movement rather than capture prey.

The creature lived during the Ordovician Period, which was 485-443 million years ago.

It almost certainly died when it was trapped by an underwater landslide. Luke Parry is the lead on the study based on this fossil, and an associate professor within the Department of Earth Sciences at the University of Oxford.

He explained to IFLScience:

“To form pyrite you need organic material, iron, and a lack of oxygen. The sediments that contain the fossils are low in organic material but high in iron and so the carcasses of the animals were like small islands where the conditions for pyrite to form are just right. The specimens of Lomankus would have been buried alive in a kind of submarine landslide called a turbidite and so this rapid burial ensure that no decay had taken place before they were buried.”

The study, published in the journal Current Biology, is working to gather as much information about this newly discovered animal as possible.

This fossil in fool’s gold was quite a find!

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