Ancient arachnid: 100-million-year-old spider found trapped in amber

  • Ancient arachnid: 100-million-year-old spider found trapped in amber

Ancient arachnid: 100-million-year-old spider found trapped in amber

But Bo Wang, also at the Chinese Academy of Sciences in Nanjing, and his colleagues examined two other fossils of the species and argue that its advanced silk-spinning apparatus shows it was part of a lineage of tailed spiders that survived until at least 100 million years ago.

About 100 million years ago, when dinosaurs roamed the Earth, four, tiny spider-like creatures became trapped in amber.

Amber, often used in jewelry, is fossilized tree resin, the oldest dating back more than 300 million years.

The extraordinary finding is described in Nature Ecology & Evolution by an global team which included earth scientist Dr Russell Garwood of Manchester University. And could this spider still be around today?

The spider lived on the islands of Myanmar - formerly Burma - during the mid-Cretaceous when Tyrannosaurus Rex ruled the planet.

Being minuscule, given that each fossil was about 7-8 mm long, including the 5 millimeters of the tail, the animal was called Chimerarachne yingi, a reference to Himera, the hybrid monster of Greek mythology, because it is a curious mixture of old and modern characteristics. He thought the presence of spinnerets pulled it to the side of spiders.

Finding the creature trapped in amber clued researchers like Paul Selden of the University of Kansas Paleontological Institute and Department of Geology into where exactly these ancient arachnids lived. "From the back, it would have looked quite similar".

Top image: The new animal resembles a spider in having fangs, male pedipalps, four walking legs and silk-producing spinnerets at its rear.

Spiders have also used their silk to make trails to guide them back to their homes and lines for diverging or trapping prey, among other purposes.

"Chimerarachne most likely wove a sheet web, and possibly a burrow lined with silk".

Four new specimens of this mysterious species - which has been dubbed Chimerarachne Yingi - have been found so far.

"We have known for a decade or so that spiders evolved from arachnids that had tails, more than 315 million years ago", Russell Garwood of The University of Manchester, a co-researcher on the study, told the BBC. The tailed finds are relatively young by comparison, and never before has there been a fossil showing spiders with tails. The tail would have been unnecessary and would have eventually been lost. We do know that the arachnid ancestor probably had a tail, and living groups like whip scorpions also have a whip-like tail.

Both describe creatures so small they could fit on the tip of a fine-point pen, with eight legs and tiny but formidable fangs.

Prof Selden said: "There's been a lot of amber being produced from northern Myanmar and its interest stepped up about 10 years ago when it was discovered this amber was mid-Cretaceous".

Amber has already built up its reputation as a time capsule for ancient species. The chimerarachne yingi isn't an actual spider, but a distant relative that crawled around southeast Asia for millions of years.

And the list of discoveries may go on. "We can only speculate that, because it was trapped in amber, we assume it was living on or around tree trunks", says Selden.