Britain’s most venomous spider – the dangerous false widow spider – has been lurking in grapes bought from a supermarket. The false widow’s bite can cause agonising swelling and result in limb amputation without hospital treatment.

An office worker found a surprise in her grapes

An office worker found a surprise in her grapes

Nichole Sarra bought a bag of grapes from the Co-Op in Cardiff Bay to enjoy with her lunch in her office; when she opened the bag she saw “dust and cobwebs” and further investigation revealed the dangerous spider lurking in the fruit. Checking further, Nichole found another false widow, this time a dead one, in the bottom of the packaging.

Nichole’s colleagues photographed the unwelcome visitors and did some online research, identifying them as the false widow spider, an identification that has since been confirmed by The British Arachnological Society. Once the spider had been identified, the office workers gave it a wide-berth; Nicole said: “We weren’t sure at first if it was a false widow spider but my colleagues looked at the markings on its back and after looking online identified it as a false widow spider. After that no one wanted to go near the grapes.”

Nicole contacted the Co-Op, sending them the photograph her colleague had taken: “I was told to go back to the grapes and get the barcode number for them so they could track it, they believed it came from Spain.”

The False Widow spider's bite can cause agonising swelling

The False Widow spider’s bite can cause agonising swelling

A spokesman for the Co-Op said: “We are committed to working closely with farmers and suppliers in order to provide a consistently great shopping experience for our customers. We are sorry that this product fell short of those expectations and will investigate the matter with our supplier.”

False Widow Spiders have reddish legs, a distinct white or cream band around the front part of the abdomen and a distinctive cream pattern in the middle of the bulbous abdomen. They are not usually aggressive unless threatened or handled.