Royal arachnaphobes beware. There is a vicious spider on the loose: up to three inches long, venomous, and with jaws strong enough to puncture human skin.
The arachnids were discovered last week in an underground maintenance tunnel in Windsor Great Park, not far from the Queen Mother's weekend residence, Royal Lodge. They are being examined by an entomolgist to try to identify them- they could be either a new, underground-dwelling species or one previously thought extinct.
British Telecom engineers doing maintenance work at Windsor found the spiders when they prised open a manhole cover and found cables swarming with the rust-red and black insects.
A BT spokesman said yesterday: "They're large and there are many of them.
"Our engineers were not attacked, but we have stopped work until we know exactly what they are."
Graham Smith, of the conservation organisation, Project-Ark, has taken samples to study. He described the spiders as an "extremely exciting find".
"The species is certainly venomous, and the jaws are strong enough to penetrate the human skin. It will take a few days to work out how dangerous they are," said Mr Smith. "There could be literally thousands and thousands of them. It would be no surprise if they are living under neath Windsor Castle itself." Remotely operated cameras are to be deployed in the tunnels around the castle to find out more, and samples of the spiders' webs are being analysed.
In the meantime, residents of the park have been warned not to touch.