Preserved Fossil in France May Shed Some Light in the Origins of Spiders

A preserved fossil in the collections of the Muséum National d'Histoire Naturelle (or National Museum of Natural History) in Paris, France was scrutinized by researchers in hopes to unveil the origin of spiders.

The fossil, according to National Geographic, was found in the ancient rock of Montceau-les-Mines in eastern France by amateur fossil hunter Daniel Sotty in the 1980s.

CBS News reported that the fossil cannot be studied in the past because half of it is buried in a rock, with only the abdomen showing.

But with the help of modern technology, researchers used high-resolution CT Scans to view the buried half of the arachnid and create a 3D model that revealed various arachnid traits, such as spider-like fangs.

According to the study published in the journal Proceedings of the Royal Society B, researchers found out that the 0.4-inch-long (10 millimeters) arachnid have features resembling spider-like mouthparts and legs.

A notable difference this arachnid has to modern spiders is the lack of spinnerets or the silk spinning organ of spiders.

The absence of spinnerets suggests that this arachnid cannot spin webs like the spiders we know, but can still produce silk that was used to line their burrows or wrap their egg sacs.

The researchers also discovered that the fossilized arachnid has a segmented abdomen like other arachnids from the same era. However, it is different from the fused abdomen possessed by modern spiders.

"This fossil is the most closely related thing we have to a spider that isn't a spider," said first author Russell Garwood from the University of Manchester in a BBC report.

This newly discovered species was named Idmonarachne brasieri, as a reference to Idmon, the father of Arachne in Greek Mythology.

Researchers said that Idmonarachne falls along the line of evolution towards modern-day spiders.

"Arachnids as a whole are an incredibly successful group," said Garwood.

They're really, really successful--but we have a very limited understanding of how they are related to each other," he added.