Ancient Arachnid Fossil may unveil Origin of Spiders

Researchers carefully examined a preserved fossil of an ‘almost spider’ to learn about the origin of spiders. The 305-million-year-old fossil was in Muséum National d'Histoire Naturelle in Paris. It was unearthed in the 1980s by a fossil hunter, Daniel Sotty, in the rock of Montceau-les-Mines.

Researchers were unable to analyze the fossil previously because a large part of it was buried in that ancient rock. Only the abdomen part of the fossil was visible.

Now, researchers have used modern technology to view the buried part of the fossil. They used high-resolution CT Scans and developed a three-dimensional model that demonstrates different traits of arachnid.

The researchers conducted a study and found that the 10-millimeter-long arachnid’s traits are similar to features of modern spiders. It has spider-like mouthparts and legs, as per the study published in the journal Proceedings of the Royal Society B.

Lack of spinnerets marks a major difference between the ancient arachnid and modern spiders, said the researchers. It clearly shows that the animal isn’t capable of spinning webs like today’s spiders.

The researchers also found that the ancient creature had a segmented abdomen similar to a number of other arachnids of that time. This fossilized critter is closely linked to today’ spider, but it isn't a spider, said Russell Garwood, a researcher from the University of Manchester and an author of the study.

The fossilized arachnid has been named Idmonarachne brasieri after Idmon, the father of Arachne. As per the researchers, the species could be an ancestor of modern-day spiders.

“Arachnids as a whole are an incredibly successful group. They're really, really successful--but we have a very limited understanding of how they are related to each other”, said Garwood.