It may not look like much, but together with other tracks in the 280 million-year-old rocks of Prehistoric Trackways National Monument in southern New Mexico, this vague form has been identified as the one and only fossil impression of a scorpion body ever found. The scorpion rested here for a time, then scurried off, and the imprint of its body eventually turned to stone.
The age of the trace fossil, as body impressions and tracks are called, takes scorpions way back to the early Permian. That confirms that scorpions have survived a lot of gigantic mass extinction events between then and now. What's more, seeing how the carbon dioxide levels in the Permian atmosphere were probably three times what they are today on Earth, it's not likely anthropogenic climate change will stop these hardy arthropods either.
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"We gave it the name Alacranichnus, which means scorpion trace (alacran is Spanish for scorpion and ichnos is Greek for trace)," said Spencer Lucas, curator at the New Mexico Museum of Natural History and Science (NMMNHS). The discovery was just published in the journal Ichnos: An International Journal for Plant and Animal Traces by scientist at the museum in Albuquerque.