Scientists have discovered the fossilised remains of a previously unknown species of arachnid boasting a scorpion-like tail even longer than its body.

The ancient arachnids - found in 100 million-year-old amber in a northern Myanmar rainforest - have tail-like appendages on their abdomens called spinnerets, which would have been used to make webs.

At 3mm, the tail extends beyond the newly christened Chimerarachne yingi's 2.5mm body and the international scientists behind its discovery say it links today's spiders with those that lived before dinosaurs.

In an article written for the Nature Ecology and Evolution journal, the researchers say it resembles a 300 million-year-old arachnid known as Attercopus, which also had a long tail and produced silk from hairs on its abdomen.

Image: The fossils date back 100 million years

Chimerarachne yingi - or the chimaera spider - have other spider-like characteristics too, including four sets of legs and fangs.


Professor Paul Selden, who was involved in the discovery of Attercopus three decades ago, said: "The new fossils are like the missing link from older animals to modern spiders."

He believes the chimaera spider would have lived in the bark of resin-producing trees during the Cretaceous period and used its long tail to sense its environment like an antennae, similarly to some types of scorpions.

As for its silk-producing capability, scientists believe it resembles a primitive family of trapdoor spiders known as the Liphistiidae, which are found in southeast Asia.

Other species of insects, including millipedes and modern spiders, were also found alongside the four chimaera fossils.

Professor Selden said it was not inconceivable that the chimaera could even still be alive today.

"They look like these older creatures so it's rather a surprise to see them alongside spiders," he said of the insects found alongside the fossils.

"You've effectively got the typically southeast Asian tropical rainforest, but with these sort of living fossils in with them.

"And in fact there's nothing to say that they're still not living there today for what we know because the region is not a well-studied area."