A primitive spider with a scorpion-like tail has been found in amber dating back 100 million years.
The arthropod has been named Chimerarachne after Chimera, a monster from Greek mythology who was made of the parts of more than one creature.
It is believed to have scurried around the undergrowth of the rainforests of Burma during the age of the dinosaurs.
Upon inspection, it was found that the creature’s tail was longer that its body – meaning it was used as a sensory device to seek out prey or escape predators.
Called a ‘telson’, the tail is seen today in scorpions – but it has never been known before in a spider.
The newly discovered species also had fangs – just like today’s arachnids – through which it would inject venom into insects it trapped in pincer like claws.
Four fossils were so perfectly preserved scientists could also identify specialised male sexual organs called pedipalps.
Similar to a tiny hypodermic needle they are used to transfer sperm to females.
The spider itself is tiny – about 2.5 millimeters in body length – excluding the nearly 3 millimeter-long tail.
Palaeontologist Professor Paul Selden, of Kansas University, said: ‘Any sort of flagelliform appendage tends to be like an antenna.
‘It’s for sensing the environment. Animals that have a long whippy tail tend to have it for sensory purposes.’
The spider has been christened Chimerarachne after the mythological Chimera.
The extraordinary finding is described in Nature Ecology & Evolution by an international team which included earth scientist Dr Russell Garwood of Manchester University.
It’s the latest in a series of Cretaceous-period fossils from the amber deposits in northern Myanmar’s Hukawng Valley.
Professor Selden said: ‘We can only speculate that, because it was trapped in amber, we assume it was living on or around tree trunks.
‘Amber is fossilised resin, so for a spider to have become trapped, it may well have lived under bark or in the moss at the foot of a tree.’
While the tailed spider was capable of producing silk due to its spinnerets it was unlikely to have constructed webs to trap bugs like many modern spiders.
It was added that the spider’s remote habitat means it is possible that tailed descendants may still be alive in Myanmar’s back country to this day.
Professor Selden added: ‘It makes us wonder if these may still be alive today.
‘We haven’t found them, but some of these forests aren’t that well-studied, and it’s only a tiny creature.’