It seems that Attercopus is a missing link, capable of producing silk but not of weaving it. “The thing that had been called the oldest known spider we have now shown is in fact more primitive than a true spider,” Professor Selden told BBC News.
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“They’re all microscopic fragments. What you’ve got is a jigsaw puzzle, with half the pieces and no picture on the box lid,” Professor Selden said. “You don’t know what it’s going to be if you haven’t got all the pieces, so having these additional pieces means it changed the idea of what it was.” The finding is important for evolutionary biologists trying to unravel the origin of spider silk.

“The puzzle about silk was this: we knew that it wasn’t used for making webs initially, for catching insects, because there were no flying insects when the earliest spiders were around,” Professor Selden said.

“Here we clearly have a spider-like animal that could produce silk but didn’t yet have these flexible spinnerets for weaving it into webs; we think that this sort of spider would leave a trail of silk as it moved along, using it to find its way back to its burrow.”