“The earliest known spider is actually from the same fossil deposit – and it definitely has spinnerets,” said lead investigator Dr Russell Garwood.
“So what we’re actually looking at is an extinct lineage that split off from the spider line some time before 305 million years ago, and those two have evolved in parallel.”
The animal has now been classified as an entirely new species outside the order of true spiders.
The intense X-ray light produced at Diamond allows scientists to scrutinise matter on a level that would be impossible with standard laboratory equipment.
Diamond’s CEO, Prof Andrew Harrison, said: “This innovative work provides us with fascinating new insights into prehistoric life on Earth.
“The Manchester group’s findings at Diamond demonstrate how central intense synchrotron light can be to piecing together complex puzzles such as this.
“The work also demonstrates the real breadth of research that goes on here at Diamond – whether it’s ancient arachnids or cutting-edge technology and medicines, we really are enabling a huge range of compelling scientific research.”